Hypothyroidism

Hypothyroidism Testing and health information

Are you looking to learn more about the key lab tests needed to diagnose Hypothyroidism? Here are the 18 key lab tests that are needed for Diagnosing Hypothyroidism.

18 Key Lab Tests for Diagnosing Hypothyroidism 

SEE BELOW THE LIST OF TESTS FOR MORE INFORMATION ABOUT  The 18 Key Lab Tests for Diagnosing Hypothyroidism


Name Matches
  • T3, Free [ 34429 ]
  • T4, Free [ 866 ]
  • TSH [ 899 ]

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • TSH [ 899 ]
  • Vitamin B12 (Cobalamin) [ 927 ]

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • Thyroid Peroxidase and Thyroglobulin Antibodies [ 7260 ]
  • TSH [ 899 ]
  • Vitamin B12 (Cobalamin) [ 927 ]
  • Vitamin B6 (Pyridoxal Phosphate ) [ 926 ]
     

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • Thyroid Peroxidase and Thyroglobulin Antibodies [ 7260 ]
  • TRAb (TSH Receptor Binding Antibody) [ 38683 ]
  • TSH [ 899 ]
  • TSI (Thyroid Stimulating Immunoglobulin) [ 30551 ]
  • Vitamin B12 (Cobalamin) [ 927 ]
  • Vitamin B6 (Pyridoxal Phosphate ) [ 926 ]
     

Description: A CBC or Complete Blood Count with Differential and Platelets test is a blood test that measures many important features of your blood’s red and white blood cells and platelets. A Complete Blood Count can be used to evaluate your overall health and detect a wide variety of conditions such as infection, anemia, and leukemia. It also looks at other important aspects of your blood health such as hemoglobin, which carries oxygen. 

Also Known As: CBC test, Complete Blood Count Test, Total Blood Count Test, CBC with Differential and Platelets test, Hemogram test  

Collection Method: Blood Draw 

Specimen Type: Whole Blood 

Test Preparation: No preparation required 

When is a Complete Blood Count test ordered?  

The complete blood count (CBC) is an extremely common test. When people go to the doctor for a standard checkup or blood work, they often get a CBC. Suppose a person is healthy and their results are within normal ranges. In that case, they may not need another CBC unless their health condition changes, or their healthcare professional believes it is necessary. 

When a person exhibits a variety of signs and symptoms that could be connected to blood cell abnormalities, a CBC may be done. A health practitioner may request a CBC to help diagnose and determine the severity of lethargy or weakness, as well as infection, inflammation, bruises, or bleeding. 

When a person is diagnosed with a disease that affects blood cells, a CBC is frequently done regularly to keep track of their progress. Similarly, if someone is being treated for a blood condition, a CBC may be performed on a regular basis to see if the treatment is working. 

Chemotherapy, for example, can influence the generation of cells in the bone marrow. Some drugs can lower WBC counts in the long run. To monitor various medication regimens, a CBC may be required on a regular basis. 

What does a Complete Blood Count test check for? 

The complete blood count (CBC) is a blood test that determines the number of cells in circulation. White blood cells (WBCs), red blood cells (RBCs), and platelets (PLTs) are three types of cells suspended in a fluid called plasma. They are largely created and matured in the bone marrow and are released into the bloodstream when needed under normal circumstances. 

A CBC is mainly performed with an automated machine that measures a variety of factors, including the number of cells present in a person's blood sample. The findings of a CBC can reveal not only the quantity of different cell types but also the physical properties of some of the cells. 

Significant differences in one or more blood cell populations may suggest the presence of one or more diseases. Other tests are frequently performed to assist in determining the reason for aberrant results. This frequently necessitates visual confirmation via a microscope examination of a blood smear. A skilled laboratory technician can assess the appearance and physical features of blood cells, such as size, shape, and color, and note any anomalies. Any extra information is taken note of and communicated to the healthcare provider. This information provides the health care provider with further information about the cause of abnormal CBC results. 

The CBC focuses on three different types of cells: 

WBCs (White Blood Cells) 

The body uses five different types of WBCs, also known as leukocytes, to keep itself healthy and battle infections and other types of harm. The five different leukocytes are eosinophiles, lymphocytes, neutrophiles, basophils, and monocytes. They are found in relatively steady numbers in the blood. Depending on what is going on in the body, these values may momentarily rise or fall. An infection, for example, can cause the body to manufacture more neutrophils in order to combat bacterial infection. The amount of eosinophils in the body may increase as a result of allergies. A viral infection may cause an increase in lymphocyte production. Abnormal (immature or mature) white cells multiply fast in certain illness situations, such as leukemia, raising the WBC count. 

RBCs (Red Blood Cells) 

The bone marrow produces red blood cells, also known as erythrocytes, which are transferred into the bloodstream after maturing. Hemoglobin, a protein that distributes oxygen throughout the body, is found in these cells. Because RBCs have a 120-day lifespan, the bone marrow must constantly manufacture new RBCs to replace those that have aged and disintegrated or have been lost due to hemorrhage. A variety of diseases, including those that cause severe bleeding, can alter the creation of new RBCs and their longevity. 

The CBC measures the number of RBCs and hemoglobin in the blood, as well as the proportion of RBCs in the blood (hematocrit), and if the RBC population appears to be normal. RBCs are generally homogeneous in size and shape, with only minor differences; however, considerable variances can arise in illnesses including vitamin B12 and folate inadequacy, iron deficiency, and a range of other ailments. Anemia occurs when the concentration of red blood cells and/or the amount of hemoglobin in the blood falls below normal, resulting in symptoms such as weariness and weakness. In a far smaller percentage of cases, there may be an excess of RBCs in the blood (erythrocytosis or polycythemia). This might obstruct the flow of blood through the tiny veins and arteries in extreme circumstances. 

Platelets 

Platelets, also known as thrombocytes, are small cell fragments that aid in the regular clotting of blood. A person with insufficient platelets is more likely to experience excessive bleeding and bruises. Excess platelets can induce excessive clotting or excessive bleeding if the platelets are not operating properly. The platelet count and size are determined by the CBC. 

Lab tests often ordered with a Complete Blood Count test: 

  • Reticulocytes
  • Iron and Total Iron Binding Capacity
  • Basic Metabolic Panel
  • Comprehensive Metabolic Panel
  • Lipid Panel
  • Vitamin B12 and Folate
  • Prothrombin with INR and Partial Thromboplastin Times
  • Sed Rate (ESR)
  • C-Reactive Protein
  • Epstein-Barr Virus
  • Von Willebrand Factor Antigen

Conditions where a Complete Blood Count test is recommended: 

  • Anemia
  • Aplastic Anemia
  • Iron Deficiency Anemia
  • Vitamin B12 and Folate Deficiency
  • Sickle Cell Anemia
  • Heart Disease
  • Thalassemia
  • Leukemia
  • Autoimmune Disorders
  • Cancer
  • Bleeding Disorders
  • Inflammation
  • Epstein-Barr Virus
  • Mononucleosis

Commonly Asked Questions: 

How does my health care provider use a Complete Blood Count test? 

The complete blood count (CBC) is a common, comprehensive screening test used to measure a person's overall health status.  

What do my Complete Blood Count results mean? 

A low Red Blood Cell Count, also known as anemia, could be due many different causes such as chronic bleeding, a bone marrow disorder, and nutritional deficiency just to name a few. A high Red Blood Cell Count, also known as polycythemia, could be due to several conditions including lung disease, dehydration, and smoking. Both Hemoglobin and Hematocrit tend to reflect Red Blood Cell Count results, so if your Red Blood Cell Count is low, your Hematocrit and Hemoglobin will likely also be low. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Differential results mean? 

A low White Blood Cell count or low WBC count, also known as leukopenia, could be due to a number of different disorders including autoimmune issues, severe infection, and lymphoma. A high White Blood Cell count, or high WBC count, also known as leukocytosis, can also be due to many different disorders including infection, leukemia, and inflammation. Abnormal levels in your White Blood Cell Count will be reflected in one or more of your different white blood cells. Knowing which white blood cell types are affected will help your healthcare provider narrow down the issue. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Platelet results mean? 

A low Platelet Count, also known as thrombocytopenia, could be due to a number of different disorders including autoimmune issues, viral infection, and leukemia. A high Platelet Count, also known as Thrombocytosis, can also be due to many different disorders including cancer, iron deficiency, and rheumatoid arthritis. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

NOTE: Only measurable biomarkers will be reported. Certain biomarkers do not appear in healthy individuals. 

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Reflex Parameters for Manual Slide Review
  Less than  Greater Than 
WBC  1.5 x 10^3  30.0 x 10^3 
Hemoglobin  7.0 g/dL  19.0 g/dL 
Hematocrit  None  75%
Platelet  100 x 10^3  800 x 10^3 
MCV  70 fL  115 fL 
MCH  22 pg  37 pg 
MCHC  29 g/dL  36.5 g/dL 
RBC  None  8.00 x 10^6 
RDW  None  21.5
Relative Neutrophil %  1% or ABNC <500  None 
Relative Lymphocyte %  1% 70%
Relative Monocyte %  None  25%
Eosinophil  None  35%
Basophil  None  3.50%
     
Platelet  <75 with no flags,
>100 and <130 with platelet clump flag present,
>1000 
Instrument Flags Variant lymphs, blasts,
immature neutrophils,  nRBC’s, abnormal platelets,
giant platelets, potential interference
     
The automated differential averages 6000+ cells. If none of the above parameters are met, the results are released without manual review.
CBC Reflex Pathway

Step 1 - The slide review is performed by qualified Laboratory staff and includes:

  • Confirmation of differential percentages
  • WBC and platelet estimates, when needed
  • Full review of RBC morphology
  • Comments for toxic changes, RBC inclusions, abnormal lymphs, and other
  • significant findings
  • If the differential percentages agree with the automated counts and no abnormal cells are seen, the automated differential is reported with appropriate comments

Step 2 - The slide review is performed by qualified Laboratory staff and includes: If any of the following are seen on the slide review, Laboratory staff will perform a manual differential:

  • Immature, abnormal, or toxic cells
  • nRBC’s
  • Disagreement with automated differential
  • Atypical/abnormal RBC morphology
  • Any RBC inclusions

Step 3 If any of the following are seen on the manual differential, a Pathologist will review the slide:

  • WBC<1,500 with abnormal cells noted
  • Blasts/immature cells, hairy cell lymphs, or megakaryocytes
  • New abnormal lymphocytes or monocytes
  • Variant or atypical lymphs >15%
  • Blood parasites
  • RBC morphology with 3+ spherocytes, RBC inclusions, suspect Hgb-C,
  • crystals, Pappenheimer bodies or bizarre morphology
  • nRBC’s

Description: A Comprehensive Metabolic Panel or CMP is a blood test that is a combination of a Basic Metabolic Panel, a Liver Panel, and electrolyte panel, and is used to screen for, diagnose, and monitor a variety of conditions and diseases such as liver disease, diabetes, and kidney disease. 

Also Known As: CMP, Chem, Chem-14, Chem-12, Chem-21, Chemistry Panel, Chem Panel, Chem Screen, Chemistry Screen, SMA 12, SMA 20, SMA 21, SMAC, Chem test

Collection Method: 

Blood Draw 

Specimen Type: 

Serum 

Test Preparation: 

9-12 hours fasting is preferred. 

When is a Comprehensive Metabolic Panel test ordered:  

A CMP is frequently requested as part of a lab test for a medical evaluation or yearly physical. A CMP test consists of many different tests that give healthcare providers a range of information about your health, including liver and kidney function, electrolyte balance, and blood sugar levels. To confirm or rule out a suspected diagnosis, abnormal test results are frequently followed up with other tests that provide a more in depth or targeted analysis of key areas that need investigating. 

What does a Comprehensive Metabolic Panel blood test check for? 

The complete metabolic panel (CMP) is a set of 20 tests that provides critical information to a healthcare professional about a person's current metabolic status, check for liver or kidney disease, electrolyte and acid/base balance, and blood glucose and blood protein levels. Abnormal results, particularly when they are combined, can suggest a problem that needs to be addressed. 

The following tests are included in the CMP: 

  • Albumin: this is a measure of Albumin levels in your blood. Albumin is a protein made by the liver that is responsible for many vital roles including transporting nutrients throughout the body and preventing fluid from leaking out of blood vessels. 

  • Albumin/Globulin Ratio: this is a ratio between your total Albumin and Globulin  

  • Alkaline Phosphatase: this is a measure of Alkaline phosphatase or ALP in your blood. Alkaline phosphatase is a protein found in all body tissues, however the ALP found in blood comes from the liver and bones. Elevated levels are often associated with liver damage, gallbladder disease, or bone disorder. 

  • Alt: this is a measure of Alanine transaminase or ALT in your blood. Alanine Aminotransferase is an enzyme found in the highest amounts in the liver with small amounts in the heart and muscles. Elevated levels are often associated with liver damage. 

  • AST: this is a measure of Aspartate Aminotransferase or AST. Aspartate Aminotransferase is an enzyme found mostly in the heart and liver, with smaller amounts in the kidney and muscles. Elevated levels are often associated with liver damage. 

  • Bilirubin, Total: this is a measure of bilirubin in your blood. Bilirubin is an orange-yellowish waste product produced from the breakdown of heme which is a component of hemoglobin found in red blood cells. The liver is responsible for removal of bilirubin from the body. 

  • Bun/Creatinine Ratio: this is a ratio between your Urea Nitrogen (BUN) result and Creatinine result.  

  • Calcium: this is a measurement of calcium in your blood. Calcium is the most abundant and one of the most important minerals in the body as it essential for proper nerve, muscle, and heart function. 

  • Calcium: is used for blood clot formation and the formation and maintenance of bones and teeth. 

  • Carbon Dioxide: this is a measure of carbon dioxide in your blood. Carbon dioxide is a negatively charged electrolyte that works with other electrolytes such as chloride, potassium, and sodium to regulate the body’s acid-base balance and fluid levels.  

  • Chloride: this is a measure of Chloride in your blood. Chloride is a negatively charged electrolyte that works with other electrolytes such as potassium and sodium to regulate the body’s acid-base balance and fluid levels. 

  • Creatinine: this is a measure of Creatinine levels in your blood. Creatinine is created from the breakdown of creatine in your muscles and is removed from your body by the kidneys. Elevated creatinine levels are often associated with kidney damage. 

  • Egfr African American: this is a measure of how well your kidneys are functioning. Glomeruli are tiny filters in your kidneys that filter out waste products from your blood for removal while retaining important substances such as nutrients and blood cells. 

  • Egfr Non-Afr. American: this is a measure of how well your kidneys are functioning. Glomeruli are tiny filters in your kidneys that filter out waste products from your blood for removal while retaining important substances such as nutrients and blood cells. 

  • Globulin: this is a measure of all blood proteins in your blood that are not albumin. 

  • Glucose: this is a measure of glucose in your blood. Glucose is created from the breakdown of carbohydrates during digestion and is the body’s primary source of energy. 

  • Potassium: this is a measure of Potassium in your blood. Potassium is an electrolyte that plays a vital role in cell metabolism, nerve and muscle function, and transport of nutrients into cells and removal of wastes products out of cells. 

  • Protein, Total: this is a measure of total protein levels in your blood. 
    Sodium: this is a measure of Sodium in your blood. Sodium is an electrolyte that plays a vital role in nerve and muscle function. 

  • Sodium: this is a measure of sodium in your blood's serum. Sodium is a vital mineral for nerve and muscle cell function.

  • Urea Nitrogen (Bun): this is a measure of Urea Nitrogen in your blood, also known as Blood UreaNitrogen (BUN). Urea is a waste product created in the liver when proteins are broken down into amino acids. Elevated levels are often associated with kidney damage. 

Lab tests often ordered with a Comprehensive Metabolic Panel test: 

  • Complete Blood Count with Differential and Platelets
  • Iron and Total Iron Binding Capacity
  • Lipid Panel
  • Vitamin B12 and Folate
  • Prothrombin with INR and Partial Thromboplastin Times
  • Sed Rate (ESR)
  • C-Reactive Protein

Conditions where a Comprehensive Metabolic Panel test is recommended: 

  • Diabetes
  • Kidney Disease
  • Liver Disease
  • Hypertension

Commonly Asked Questions: 

How does my health care provider use a Comprehensive Metabolic Panel test? 

The comprehensive metabolic panel (CMP) is a broad screening tool for assessing organ function and detecting diseases like diabetes, liver disease, and kidney disease. The CMP test may also be requested to monitor known disorders such as hypertension and to check for any renal or liver-related side effects in persons taking specific drugs. If a health practitioner wants to follow two or more separate CMP components, the full CMP might be ordered because it contains more information. 

What do my Comprehensive Metabolic Panel test results mean? 

The results of the tests included in the CMP are usually analyzed together to look for patterns. A single abnormal test result may indicate something different than a series of abnormal test findings. A high result on one of the liver enzyme tests, for example, is not the same as a high result on several liver enzyme tests. 

Several sets of CMPs, frequently performed on various days, may be examined to gain insights into the underlying disease and response to treatment, especially in hospitalized patients. 

Out-of-range findings for any of the CMP tests can be caused by a variety of illnesses, including kidney failure, breathing issues, and diabetes-related complications, to name a few. If any of the results are abnormal, one or more follow-up tests are usually ordered to help determine the reason and/or establish a diagnosis. 

Is there anything else I should know? 

A wide range of prescription and over-the-counter medications can have an impact on the results of the CMP's components. Any medications you're taking should be disclosed to your healthcare professional. Similarly, it is critical to provide a thorough history because many other circumstances can influence how your results are interpreted. 

What's the difference between the CMP and the BMP tests, and why would my doctor choose one over the other? 

The CMP consists of 14 tests, while the basic metabolic panel (BMP) is a subset of those with eight tests. The liver (ALP, ALT, AST, and bilirubin) and protein (albumin and total protein) tests are not included. If a healthcare provider wants a more thorough picture of a person's organ function or to check for specific illnesses like diabetes or liver or kidney disease, he or she may prescribe a CMP rather than a BMP. 

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Please note the following regarding BUN/Creatinine ratio: 

The lab does not report the calculation for the BUN/Creatinine Ratio unless one or both biomarkers’ results fall out of the published range. 

If you still wish to see the value, it's easy to calculate. Simply take your Urea Nitrogen (BUN) result and divide it by your Creatinine result.  

As an example, if your Urea Nitrogen result is 11 and your Creatinine result is 0.86, then you would divide 11 by 0.86 and get a BUN/Creatinine Ratio result of 12.79. 


Description: Hemoglobin A1c is the protein Hemoglobin found in red blood cells, but with glucose attached to it. Hemoglobin A1c is used to check for and monitor diabetes as it shows average blood glucose levels over the past 2 to 3 months.

Also Known As: A1c Test, HbA1c Test, Glycohemoglobin Test, Glycated Hemoglobin Test, Glycosylated Hemoglobin Test, HbA1c Test

Collection Method: Blood Draw

Specimen Type: Whole Blood

Test Preparation: No preparation required

When is a Hemoglobin A1c test ordered?

A1c may be requested as part of a routine physical examination or when a practitioner suspects a patient of having diabetes due to characteristic signs or symptoms of high blood sugar, such as:

  • Increased thirst and fluid intake
  • Increased urination
  • Increase in hunger
  • Fatigue
  • Vision is hazy
  • Infections that take a long time to heal

Adults who are overweight and have the following additional risk factors may consider doing the A1c test:

  • Physically inactive
  • Diabetes in a first-degree relative
  • Race/ethnicity that is at high risk such as African Americans, Latinos, Native Americans, Asian Americans, and Pacific Islanders
  • Blood pressure that is high
  • A lipid profile that is abnormal.
  • Polycystic ovarian syndrome 
  • Cardiovascular disease 
  • Insulin resistance and other conditions links to insulin resistance

People who have not been diagnosed with diabetes but have been assessed to be at an increased risk of developing diabetes should have their A1c levels tested at least once a year.

Monitoring

The A1c test may be performed 2 to 4 times a year, depending on the type of diabetes a person has, how well their diabetes is controlled, and the healthcare provider's recommendations. If diabetics are fulfilling treatment goals and have stable glycemic control, the American Diabetes Association advises A1c testing at least twice a year. A1c may be ordered quarterly when someone is first diagnosed with diabetes or if control isn't good.

What does a Hemoglobin A1c blood test check for?

Hemoglobin A1c, often known as A1c or glycated hemoglobin, is hemoglobin that has been attached to glucose. By assessing the proportion of glycated hemoglobin, the A1c test determines the average quantity of glucose in the blood during the previous 2 to 3 months.

Hemoglobin is a protein present inside red blood cells that transports oxygen.

Glycated hemoglobin is generated in proportion to the amount of glucose in the blood. Once glucose attaches to hemoglobin, it stays there for the duration of the red blood cell's life, which is usually about 120 days. The most common kind of glycated hemoglobin is known as A1c. A1c is created on a daily basis and is gradually removed from the bloodstream as older RBCs die and younger RBCs replace them.

This test can be used to detect and diagnose diabetes, as well as the risk of developing it. According to the American Diabetes Association's standards of medical care in diabetes, diabetes can be diagnosed using either A1c or glucose.

This test can also be used to track the progress of a diabetic patient's treatment. It aids in determining how well a person's glucose levels have been controlled over time by medication. An A1c of less than 7% suggests good glucose control and a lower risk of diabetic complications for the majority of diabetics for monitoring reasons.

Lab tests often ordered with a Hemoglobin A1c test:

  • Complete Blood Count
  • Glucose
  • Frucstosamine
  • Albumin
  • Comprehensive Metabolic Panel
  • Microalbumin w/creatinine
  • Lipid panel

Conditions where a Hemoglobin A1c test is recommended:

  • Type 1 Diabetes
  • Type 2 Diabetes

How does my health care provider use a Hemoglobin A1c test?

Adults can use the hemoglobin A1c test to screen for and diagnose diabetes and prediabetes.

A fasting glucose or oral glucose tolerance test should be done to screen or diagnose diabetes in these instances.

The A1c test is also used to track diabetics' glucose control over time. Diabetics strive to maintain blood glucose levels that are as close to normal as feasible. This helps to reduce the risks of consequences associated with chronically high blood sugar levels, such as progressive damage to body organs such as the kidneys, eyes, cardiovascular system, and nerves. The result of the A1c test depicts the average quantity of glucose in the blood over the previous 2-3 months. This can help diabetics and their healthcare professionals determine whether the steps they're taking to control their diabetes are working or if they need to be tweaked.

A1c is a blood test that is usually used to help newly diagnosed diabetics identify how high their uncontrolled blood glucose levels have been in the previous 2-3 months. The test may be ordered multiple times throughout the control period, and then at least twice a year after that to ensure that good control is maintained.

What does my Hemoglobin A1c test result mean?

HbA1c levels is currently reported as a percentage for monitoring glucose control, and it is suggested that most diabetics try to keep their hemoglobin A1c below 7%. The closer diabetics can keep their A1c to the therapeutic objective of less than 7% without experiencing abnormally low blood glucose, the better their diabetes is controlled. The risk of problems rises as the A1c rises.

However, a person with type 2 diabetes may have an A1c goal set by their healthcare professional. The length of time since diagnosis, the presence of other diseases as well as diabetes complications, the risk of hypoglycemia complications, life expectancy, and whether or not the person has a support system and healthcare resources readily available are all factors that may influence the goal.

For example, a person with heart disease who has had type 2 diabetes for many years without diabetic complications may have a higher A1c target set by their healthcare provider, whereas someone who is otherwise healthy and newly diagnosed may have a lower target set by their healthcare provider as long as low blood sugar is not a significant risk.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


Description: Iron and Total Iron Binding Capacity is a blood panel used to determine iron levels in your blood, your body’s ability to transport iron, and help diagnose iron-deficiency and iron overload.

Also Known As: Serum Iron Test, Serum Fe Test, Iron Binding Capacity Test, IBC Test, Serum Iron-Binding Capacity Siderophilin Test, TIBC Test, UIBC Test, Iron Lab Test, TIBC Blood test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a Iron and Total Iron Binding Capacity test ordered?

When a doctor feels that a person's symptoms are caused by iron overload or poisoning, an iron and TIBC test, as well ferritin assays, may be done. These may include the following:

  • Joint discomfort
  • Weakness and exhaustion
  • Energy deficiency
  • Pain in the abdomen
  • Suffering from a lack of sexual desire
  • Problems with the heart

When a child is suspected of ingesting too many iron tablets, a serum iron test is required to detect the poisoning and to determine its severity.

A doctor may also request iron and TIBC when the results of a standard CBC test are abnormal, such as a low hematocrit or hemoglobin, or when a doctor suspects iron deficiency based on signs and symptoms such as:

  • Chronic tiredness/fatigue
  • Dizziness
  • Weakness
  • Headaches
  • Skin that is pale

What does a Iron and Total Iron Binding Capacity blood test check for?

Iron is a necessary ingredient for survival. It is a vital component of hemoglobin, the protein in red blood cells that binds and releases oxygen in the lungs and throughout the body. It is required in small amounts to help form normal red blood cells and is a critical part of hemoglobin, the protein in RBCs that binds oxygen in the lungs and releases it as blood circulates to other parts of the body.

By detecting numerous components in the blood, iron tests are ordered to determine the quantity of iron in the body. These tests are frequently ordered at the same time, and the data are analyzed together to determine the diagnosis and/or monitor iron deficiency or overload.

The level of iron in the liquid component of the blood is measured by serum iron.

Total iron-binding capacity is a measurement of all the proteins in the blood that may bind to iron, including transferrin.

The percentage of transferrin that has not yet been saturated is measured by the UIBC. Transferrin levels are also reflected in the UIBC.

Low iron levels can cause anemia, resulting in a decrease in the production of microcytic and hypochromic RBCs. Large amounts of iron, on the other hand, might be hazardous to the body. When too much iron is absorbed over time, iron compounds build up in tissues, particularly the liver, heart, and pancreas.

Normally, iron is absorbed from food and distributed throughout the body by binding to transferrin, a liver protein. About 70% of the iron delivered is used in the synthesis of hemoglobin in red blood cells. The rest is stored as ferritin or hemosiderin in the tissues, with minor amounts being utilized to make other proteins like myoglobin and enzymes.

Insufficient intake, limited absorption, or increased dietary requirements, as observed during pregnancy or with acute or chronic blood loss, are all signs of iron deficiency. Excessive intake of iron pills can cause acute iron overload, especially in children. Excessive iron intake, genetic hemochromatosis, multiple blood transfusions, and a few other disorders can cause chronic iron overload.

Lab tests often ordered with a Iron and Total Iron Binding Capacity test:

  • Complete Blood Count
  • Ferritin
  • Transferrin
  • Zinc Protoporphyrin

Conditions where a Iron and Total Iron Binding Capacity test is recommended:

  • Anemia
  • Hemochromatosis

How does my health care provider use a Iron and Total Iron Binding Capacity test?

The amount of circulating iron in the blood, the capacity of the blood to carry iron, and the amount of stored iron in tissues can all be determined by ordering one or more tests. Testing can also assist distinguish between different types of anemia

The level of iron in the blood is measured by serum iron.

Total iron-binding capacity is a measurement of all the proteins in the blood that may bind to iron, including transferrin. The TIBC test is a useful indirect assessment of transferrin because it is the predominant iron-binding protein. In response to the requirement for iron, the body generates transferrin. Transferrin levels rise when iron levels are low, and vice versa. About one-third of the binding sites on transferrin are used to transport iron in healthy humans.

The reserve capacity of transferrin, or the part of transferrin that has not yet been saturated, is measured by UIBC. Transferrin levels are also reflected in the UIBC.

The iron test result, as well as TIBC or UIBC, are used to calculate transferrin saturation. It represents the proportion of transferrin that is iron-saturated.

Ferritin is the major storage protein for iron inside cells, and serum ferritin represents the quantity of stored iron in the body.

These tests are frequently ordered together, and the results can assist the doctor figure out what's causing the iron deficit or overload.

Additional information about iron

A balance between the quantity of iron received into the body and the amount of iron lost is required to maintain normal iron levels. Because a tiny quantity of iron is lost each day, a deficiency will develop if too little iron is consumed. In healthy persons, there is usually enough iron to prevent iron deficiency and/or iron deficiency anemia, unless they eat a bad diet. There is a greater need for iron in some circumstances. People who have persistent gut bleeding or women who have heavy menstrual periods lose more iron than they should and can develop iron deficiency. Females who are pregnant or breastfeeding lose iron to their babies and may develop an iron shortage if they do not consume enough supplemental iron. Children may require additional iron, especially during periods of rapid growth, and may suffer iron shortage.

Low serum iron can also arise when the body is unable to adequately utilize iron. The body cannot correctly utilize iron to generate additional red cells in many chronic disorders, particularly malignancies, autoimmune diseases, and chronic infections. As a result, transferrin production slows, serum iron levels drop because little iron is absorbed from the stomach, and ferritin levels rise. Malabsorption illnesses like sprue syndrome can cause iron deficiency.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


Description: A Lipid Panel is a blood test that measures your cholesterol levels to evaluate your risk of cardiovascular disease.

Also Known As: Lipid Profile Test, Lipid Test, Cholesterol Profile Test, Cholesterol Panel Test, Cholesterol Test, Coronary Risk Panel Test, lipid blood test, Lipid w/Ratios Test, Cholesterol Ratio test, blood cholesterol Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: Patient should be fasting 9-12 hours prior to collection.

When is a Lipid Panel with Ratios test ordered?

A fasting lipid profile should be done about every five years in healthy persons who have no additional risk factors for heart disease. A single total cholesterol test, rather than a complete lipid profile, may be used for initial screening. If the screening cholesterol test result is high, a lipid profile will almost certainly be performed.

More regular testing with a full lipid profile is indicated if other risk factors are present or if earlier testing revealed a high cholesterol level.

Other risk factors, in addition to high LDL cholesterol, include:

  • Smoking
  • Obesity or being overweight
  • Unhealthy eating habits
  • Not getting enough exercise and being physically inactive
  • Older age
  • Having hypertension
  • Premature heart disease in the family
  • Having experienced a heart attack or having pre-existing heart disease

Diabetes or pre-diabetes is a condition in which a person has High HDL is a "negative risk factor," and its existence permits one risk factor to be removed from the total.

The American Academy of Pediatrics recommends routine lipid testing for children and young adults. Children and teenagers who are at a higher risk of developing heart disease as adults should be screened with a lipid profile earlier and more frequently. A family history of heart disease or health problems such as diabetes, high blood pressure, or being overweight are some of the risk factors, which are comparable to those in adults. According to the American Academy of Pediatrics, high-risk children should be examined with a fasting lipid profile between the ages of 2 and 8.

A lipid profile can also be done at regular intervals to assess the effectiveness of cholesterol-lowering lifestyle changes like diet and exercise, as well as pharmacological therapy like statins.

What does a Lipid Panel with Ratios blood test check for?

Lipids are a class of fats and fat-like compounds that are essential components of cells and energy sources. The level of certain lipids in the blood is measured by a lipid profile.

Lipoprotein particles transport two key lipids, cholesterol and triglycerides, through the bloodstream. Protein, cholesterol, triglyceride, and phospholipid molecules are all present in each particle. High-density lipoproteins, low-density lipoproteins, and very low-density lipoproteins are the three types of particles assessed with a lipid profile.

It's critical to keep track of and maintain optimal levels of these lipids in order to stay healthy. While the body creates the cholesterol required for normal function, some cholesterol is obtained from the diet. A high amount of cholesterol in the blood can be caused by eating too many foods high in saturated fats and trans fats or having a hereditary tendency. The excess cholesterol may form plaques on the inside walls of blood vessels. Plaques can constrict or block blood channel openings, causing artery hardening and raising the risk of a variety of health problems, including heart disease and stroke. Although the explanation for this is unknown, a high level of triglycerides in the blood is linked to an increased risk of developing cardiovascular disease.

A lipid profile consists of the following elements:

  • Cholesterol total
  • HDL Cholesterol - commonly referred to as "good cholesterol" since it eliminates excess cholesterol from the body and transports it to the liver for elimination.
  • LDL Cholesterol - commonly referred to as "bad cholesterol" because it deposits excess cholesterol in the walls of blood arteries, contributing to atherosclerosis.
  • Triglycerides
  • Ratio of LDL to HDL cholesterol

Lab tests often ordered with a Lipid Panel with Ratios test:

  • CBC (Blood Count Test) with Smear Review
  • Comprehensive Metabolic Panel
  • Direct LDL
  • VLDL
  • Lp-PLA2
  • Apolipoprotein A1
  • Apolipoprotein B
  • Lipoprotein (a)
  • Lipoprotein Fractionation Ion Mobility (LDL Particle Testing)

Conditions where a Lipid Panel with Ratios test is recommended:

  • Hypertension
  • Cardiovascular Disease
  • Heart Disease
  • Stroke

Commonly Asked Questions:

How does my health care provider use a Lipid Panel with Ratios test?

The lipid profile is used as part of a cardiac risk assessment to help determine an individual's risk of heart disease and, if there is a borderline or high risk, to help make treatment options.

Lipids are a class of fats and fat-like compounds that are essential components of cells and energy sources. It's critical to keep track of and maintain optimal levels of these lipids in order to stay healthy.

To design a therapy and follow-up strategy, the results of the lipid profile are combined with other recognized risk factors for heart disease. Treatment options may include lifestyle changes such as diet and exercise, as well as lipid-lowering drugs such as statins, depending on the results and other risk factors.

A normal lipid profile test measures the following elements:

  • Total cholesterol is a test that determines how much cholesterol is present in all lipoprotein particles.
  • HDL Cholesterol — measures hdl cholesterol in particles, sometimes referred to as "good cholesterol" since it eliminates excess cholesterol and transports it to the liver for elimination.
  • LDL Cholesterol – estimates the cholesterol in LDL particles; sometimes known as "bad cholesterol" since it deposits excess cholesterol in blood vessel walls, contributing to atherosclerosis. The amount of LDL Cholesterol is usually estimated using the total cholesterol, HDL Cholesterol, and triglycerides readings.
  • Triglycerides – triglycerides are measured in all lipoprotein particles, with the highest concentration in very-low-density lipoproteins.
  • As part of the lipid profile, several extra information may be presented. The results of the above-mentioned tests are used to determine these parameters.
  • VLDL Cholesterol — derived using triglycerides/5; this calculation is based on the typical VLDL particle composition.
  • Non-HDL Cholesterol - the result of subtracting total cholesterol from HDL Cholesterol.
  • Cholesterol/HDL ratio — total cholesterol to HDL Cholesterol ratio computed.

An expanded profile may include the amount and concentration of low-density lipoprotein particles. Rather than assessing the amount of LDL cholesterol, this test counts the number of LDL particles. This figure is thought to more accurately reflect the risk of heart disease in some persons.

What do my Lipid Panel test results mean?

Healthy lipid levels, in general, aid in the maintenance of a healthy heart and reduce the risk of heart attack or stroke. A health practitioner would analyze the results of each component of a lipid profile, as well as other risk factors, to assess a person's total risk of coronary heart disease, if therapy is required, and, if so, which treatment will best serve to reduce the person's risk of heart disease.

The Adult Treatment Panel III of the National Cholesterol Education Program published guidelines for measuring lipid levels and selecting treatment in 2002. The American College of Cardiology and the American Heart Association announced updated cholesterol therapy guidelines in 2013 to minimize the risk of cardiovascular disease in adults. These guidelines suggest a different treatment method than the NCEP guidelines. Cholesterol-lowering medications are now chosen based on the 10-year risk of atherosclerotic cardiovascular disease and other criteria, rather than on LDL-C or non-HDL-C objectives.

The revised guidelines include an evidence-based risk calculator for ASCVD that may be used to identify people who are most likely to benefit from treatment. It's for adults between the ages of 40 and 79 who don't have a heart condition. The computation takes into account a number of characteristics, including age, gender, race, total cholesterol, HDL-C, blood pressure, diabetes, and smoking habits. The new guidelines also suggest comparing therapeutic response to LDL-C baseline readings, with decrease criteria varying depending on the degree of lipid-lowering medication therapy.

Unhealthy lipid levels, as well as the presence of additional risk factors like age, family history, cigarette smoking, diabetes, and high blood pressure, may indicate that the person being examined needs to be treated.

The NCEP Adult Treatment Panel III guidelines specify target LDL cholesterol levels based on the findings of lipid testing and these other main risk factors. Individuals with LDL-C levels over the target limits will be treated, according to the guidelines.

According to the American Academy of Pediatrics, screening youths with risk factors for heart disease with a full, fasting lipid panel is advised. Fasting is not required prior to lipid screening in children who do not have any risk factors. For non-fasting lipid screening, non-high-density lipoprotein cholesterol is the preferred test. Non-HDL-C is computed by subtracting total cholesterol and HDL-C from total cholesterol and HDL-C.

Is there anything else I should know?

The measurement of triglycerides in people who haven't fasted is gaining popularity. Because most of the day, blood lipid levels reflect post-meal levels rather than fasting levels, a non-fasting sample may be more representative of the "usual" circulating level of triglyceride. However, because it is still unclear how to interpret non-fasting levels for assessing risk, the current recommendations for fasting before lipid tests remain unchanged.

A fasting lipid profile is usually included in a routine cardiac risk assessment. In addition, research into the utility of additional non-traditional cardiac risk markers, such as Lp-PLA2, is ongoing. A health care provider may use one or more of these markers to help determine a person's risk, but there is no consensus on how to use them and they are not widely available.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


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Description: A RT3 test is a laboratory test that checks for Reverse T3 levels in your blood’s serum.

Also Known As: T3 Reverse test, REVT3 Test, RT3 Test, T3R Test, Reverse T3 Test, Reverse Triiodothyronine Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is this test ordered?

Reverse T3 is used to identify stress on the body due to many factors including extreme dieting, surgery, liver and kidney disease, insulin dependent diabetes, serious injury, and chronic alcohol consumption.

What is being tested?

Reverse T3 is a derivative of Thyroxine T4. T4 becomes the active thyroid hormone Triiodothyronine T3 when it loses one of its iodine atoms. T4 is also converted by the body into Reverse T3, which is an inactive version of T3 that lacks T3's metabolic function. Reverse T3 is thought to be produced by the body to conserve energy during times of severe illness and stress.

Related Tests and Panels:

  • T3 Free
  • T3 Total
  • T4 Free
  • T4 Total
  • TSH
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies

Related Conditions:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer
  • Kidney Disease
  • Liver Disease
  • Alcoholism
  • Stress
  • Diabetes

How is the Reverse T3 test used by my healthcare provider?

Results of a Reverse T3 test are used in combination with results of T4 tests, T3 Tests, thyroid antibodies, and TSH in assessing a patient’s symptoms and thyroid function.

What does my Reverse T3 test result mean?

High levels of T3 Reverse indicate that an excessive amount of T4 is being converted into Reverse T3 instead of active T3. This can cause signs of hypothyroidism, a thyroid condition often referred to as underactive thyroid, even when other thyroid hormones are within normal ranges. Elevated levels of RT3 levels can also be a sign of illness and stress and as the body converts more T4 into Reverse T3 when experiencing illnesses and stress.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results


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Description: A T3 Total test is a blood test that measures triiodothyronine levels in your blood’s serum to evaluate your thyroid’s health and to screen for, diagnose, and monitor thyroid disorders such as hyperthyroidism.

Also Known As: Total T3 Test, Triiodothyronine Test, T3 Test, Bound T3

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a T3 Total test ordered?

When a person's TSH test results are abnormal, a total T3 test may be recommended. When a person has symptoms that imply hyperthyroidism, it may be requested as part of the investigational workup, especially if the free T4 level is not elevated.

The following are possible signs and symptoms:

  • Heart rate has increased.
  • Anxiety
  • Loss of weight
  • Sleeping problems
  • Hand tremors
  • Weakness
  • Diarrhea
  • Visual disturbances, light sensitivity
  • Puffiness around the eyes, dryness, discomfort, and, in some cases, bulging of the eyes are all possible side effects.

Total T3 may be ordered at regular intervals to monitor a known thyroid disease or to assess the efficacy of hyperthyroidism treatment.

What does a T3 Total blood test check for?

T3 is one of two key hormones produced by the thyroid gland, a small butterfly-shaped organ near the base of the throat that sits flat across the windpipe. Thyroxine is the other primary thyroid hormone, and together they help govern the rate at which the body utilizes energy. T3 in the blood is almost entirely linked to protein. The remaining portion is free and is the hormone's physiologically active form. Tests can determine the amount of free T3 or total T3 in the blood.

A feedback system controls T3 and T4 production. The hypothalamus releases thyrotropin releasing hormone when thyroid hormone levels in the blood drop, which prompts the pituitary gland to create and release thyroid-stimulating hormone. The thyroid gland is thus stimulated to create and/or release more thyroid hormones as a result of TSH. T4 is the most common thyroid hormone produced. This hormone is generally inactive, but in the liver and other tissues, it is transformed into the considerably more active T3.

If the thyroid gland produces too much T4 and T3, the person may have symptoms like uneasiness, hand tremors, weight loss, sleeplessness, and puffiness around dry, itchy eyes. The person's eyes may be unable to move normally and appear to be glaring in some circumstances. The eyeballs may also appear to bulge in some circumstances.

If the thyroid gland does not produce enough thyroid hormones, the person may experience weight gain, dry skin, lethargy, and constipation, which are all signs and symptoms of hypothyroidism and a slower metabolism. Thyroid hormone levels in the blood might be low or high due to thyroid malfunction, or in rare cases, insufficient or excessive TSH production due to a pituitary issue.

Autoimmune illnesses are the most common causes of thyroid dysfunction. Hyperthyroidism is caused by Graves disease, but it can also be caused by thyroiditis, thyroid malignancy, or high TSH production. Total T3 can be used to diagnose and monitor the impact of certain disorders on thyroid hormone production.

Lab tests often ordered with a T3 Total test:

  • TSH
  • T3 Free
  • T4 Free
  • T4 Total
  • T3 Reverse
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies

Conditions where a T3 Total test is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

How does my health care provider use a T3 Total test?

Thyroid function is measured with a total triiodothyronine test. It's usually ordered to assist identify hyperthyroidism, but it can also be used to track a person's therapy for a thyroid problem.

Thyroid hormones T3 and T4 are generated by the thyroid gland. They aid in the regulation of the rate at which the body expends energy and are governed by a feedback system. Thyroid-stimulating hormone boosts T4 and T3 synthesis and release. The liver and other tissues convert T4 into T3 as needed.

The majority of T4 and T3 in the blood is attached to protein, while just a small amount is free. Total T4, free T4, total T3, and free T3 can all be measured in blood tests.

Because the majority of T3 is coupled to protein, total T3 can be influenced by protein levels and binding ability, but free T3 is unaffected. Some professional standards, however, advocate total T3, thus either test can be used to evaluate thyroid function. To assist diagnose Graves disease, an autoimmune illness that is the most prevalent cause of hyperthyroidism, free T3 or total T3 may be ordered together with thyroid antibodies.

Following an abnormal TSH, a total T3 test is generally done, especially if the free T4 test is not high.

What does my T3 Total Test result mean?

Thyroid hormone levels that are high or low suggest a mismatch between the body's needs and supplies, but they don't inform the doctor what's causing the excess or deficiency.

If someone is being treated for hyperthyroidism with anti-thyroid medication and their free or total T3 levels are normal, the medicine is likely beneficial in treating the illness. If the free or total T3 or free T4 levels are high, the medication isn't working to address the problem, and the person may be having hyperthyroidism symptoms.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results


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Description: A T3 Free test is a blood test that measures unbound triiodothyronine levels in your blood’s serum to evaluate your thyroid’s health and to screen for, diagnose, and monitor thyroid disorders such as hyperthyroidism.

Also Known As: Free T3 Test, Free Triiodothyronine Test, FT3 Test, T3F Test, Unbound T3 Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a T3 Free test ordered?

When a person's TSH test results are abnormal, a free T3 test may be recommended. When a person has symptoms that imply hyperthyroidism, it may be requested as part of the investigational workup, especially if the free T4 level is not elevated.

The following are possible signs and symptoms:

  • Heart rate has increased.
  • Anxiety
  • Loss of weight
  • Sleeping problems
  • Hand tremors
  • Weakness
  • Diarrhea
  • Visual disturbances, light sensitivity
  • Puffiness around the eyes, dryness, discomfort, and, in some cases, bulging of the eyes are all possible side effects.

Free T3 may be ordered at regular intervals to monitor a known thyroid disease or to assess the efficacy of hyperthyroidism treatment.

What does a T3 Free test check for?

T3 is one of two key hormones produced by the thyroid gland, a small butterfly-shaped organ near the base of the throat that sits flat across the windpipe. Thyroxine is the other primary thyroid hormone, and together they help govern the rate at which the body utilizes energy. T3 in the blood is almost entirely linked to protein. The remaining portion is free and is the hormone's physiologically active form. Tests can determine the amount of free T3 or total T3 in the blood.

A feedback system controls T3 and T4 production. The hypothalamus releases thyrotropin releasing hormone when thyroid hormone levels in the blood drop, which prompts the pituitary gland to create and release thyroid-stimulating hormone. The thyroid gland is thus stimulated to create and/or release more thyroid hormones as a result of TSH. T4 is the most common thyroid hormone produced. This hormone is generally inactive, but in the liver and other tissues, it is transformed into the considerably more active T3.

If the thyroid gland produces too much T4 and T3, the person may have symptoms like uneasiness, hand tremors, weight loss, sleeplessness, and puffiness around dry, itchy eyes. The person's eyes may be unable to move normally and appear to be glaring in some circumstances. The eyeballs may also appear to bulge in some circumstances.

If the thyroid gland does not produce enough thyroid hormones, the person may experience weight gain, dry skin, lethargy, and constipation, which are all signs and symptoms of hypothyroidism and a slower metabolism. Thyroid hormone levels in the blood might be low or high due to thyroid malfunction, or in rare cases, insufficient or excessive TSH production due to a pituitary issue.

Autoimmune illnesses are the most common causes of thyroid dysfunction. Hyperthyroidism is caused by Graves disease, but it can also be caused by thyroiditis, thyroid malignancy, or high TSH production. Total T3 can be used to diagnose and monitor the impact of certain disorders on thyroid hormone production.

Lab tests often ordered with a T3 Free test:

  • TSH
  • T3 Total
  • T4 Free
  • T4 Total
  • T3 Reverse
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies

Conditions where a T3 Free test is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

How does my health care provider use a T3 Free test?

Thyroid function is measured with a free triiodothyronine test. It's usually ordered to assist identify hyperthyroidism, but it can also be used to track a person's therapy for a thyroid problem.

Thyroid hormones T3 and T4 are generated by the thyroid gland. They aid in the regulation of the rate at which the body expends energy and are governed by a feedback system. Thyroid-stimulating hormone boosts T4 and T3 synthesis and release. The liver and other tissues convert T4 into T3 as needed.

The majority of T4 and T3 in the blood is attached to protein, while just a small amount is free. Total T4, free T4, total T3, and free T3 can all be measured in blood tests.

Because the majority of T3 is coupled to protein, total T3 can be influenced by protein levels and binding ability, but free T3 is unaffected. Some professional standards, however, advocate total T3, thus either test can be used to evaluate thyroid function. To assist in diagnosing Graves disease, an autoimmune illness that is the most prevalent cause of hyperthyroidism, free T3 or total T3 may be ordered together with thyroid antibodies.

Following an abnormal TSH, a free T3 test is generally done, especially if the free T4 test is not high.

What does my T3 Free result mean?

Thyroid hormone levels that are high or low suggest a mismatch between the body's needs and supplies, but they don't inform the doctor what's causing the excess or deficiency.

If someone is being treated for hyperthyroidism with anti-thyroid medication and their free or total T3 levels are normal, the medicine is likely beneficial in treating the illness. If the free or total T3 or free T4 levels are high, the medication isn't working to address the problem, and the person may be having hyperthyroidism symptoms.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results


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Description: A T4 Total test is a blood test that measures thyroxine free levels in your blood’s serum to evaluate your thyroid’s health and to screen for, diagnose, and monitor thyroid disorders such as hypothyroidism.

Also Known As: Total T4 Test, Total Thyroxine Test, T4 Test, T4, T4 Total Test, Bound T4 Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a T4 Total test ordered?

When a person exhibits symptoms of hyperthyroidism or hypothyroidism, a Total T4 test may be administered, especially if a TSH test result is abnormal.

Hyperthyroidism can cause the following signs and symptoms:

  • Heart rate has increased.
  • Anxiety
  • Loss of weight
  • Sleeping problems
  • Hand tremors
  • Weakness
  • Diarrhea
  • Visual disturbances, light sensitivity
  • Puffiness around the eyes, dryness, discomfort, and, in some cases, bulging of the eyes are all possible side effects.

Hypothyroidism can cause the following symptoms:

  • gaining weight
  • Skin that is dry
  • Constipation
  • Intolerance to the cold
  • Skin that is puffy
  • Hair loss
  • Fatigue
  • Women's menstrual irregularities

When a person is being treated for a thyroid problem, Total T4 testing, along with other thyroid tests, may be requested on a regular basis.

Thyroid testing will most likely be ordered early and late in the pregnancy, as well as for a period after delivery, to monitor the mother and baby in pregnant women with thyroid abnormalities.

In the United States, thyroid hormone screening is routinely performed on babies as part of newborn screening programs.

What does a T4 Total blood test check for?

The thyroid gland, a small butterfly-shaped structure that lays on the windpipe towards the bottom of the throat, produces one of two primary hormones: thyroxine. Triiodothyronine is the other primary thyroid hormone, and together they help govern the rate at which the body utilizes energy. T4 in the blood is almost entirely linked to protein. The remaining portion is free and is the hormone's biologically active form. This test determines how much Bound T4 is present in the blood.

A feedback loop controls T4 production. The hypothalamus releases thyrotropin releasing hormone, which encourages the pituitary gland to generate and release thyroid-stimulating hormone when the amount of T4 in the blood drops. The thyroid gland is thus stimulated to produce and/or release more T4 as a result of TSH. TSH release is blocked as T4 content in the blood rises.

T4 accounts for over 90% of thyroid hormones. The thyroid gland releases accumulated T4 into circulation when the body requires it. T4 is either free or bound to protein in the blood. The amount of free T4 in the body is just about 0.1 percent of total T4. In the liver or other tissues, T4 is converted to T3. T3, like T4, is mainly attached to protein, however the physiologically active forms of T3 and T4 are the free versions. Free T3 in circulation is 4 to 5 times more active than free T4.

Dry skin, weight gain, cold intolerance, weariness, and irregular menstruation are among signs of hypothyroidism that occur when the thyroid gland does not produce enough T4 due to thyroid malfunction or insufficient TSH. Myxedema, or severe untreated hypothyroidism, can cause heart failure, convulsions, and coma. Hypothyroidism in children can slow growth and sexual development.

When the thyroid gland generates too much T4, the rate of a person's body functions increases, resulting in hyperthyroidism symptoms such as anxiety, increased heart rate, difficulty sleeping, weight loss, puffiness and dry itchy eyes, and hand tremors.

The most prevalent causes of thyroid dysfunction are connected to autoimmune illnesses. Hyperthyroidism is caused by Graves disease, while hypothyroidism is caused by Hashimoto thyroiditis. Thyroiditis, thyroid malignancy, and excessive or insufficient TSH production can all induce hyperthyroidism or hypothyroidism. By measuring Total T4, the influence of these variables on thyroid hormone synthesis can be recognized and monitored.

Note: Free T4 Index (T7) will only be calculated and reported if test code code 861 (T3 Uptake) is ordered as well.

Lab tests often ordered with a T4 Total test:

  • TSH
  • T3 Total
  • T3 Free
  • T4 Free
  • T3 Reverse
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies

Conditions where a T4 Total test is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

How does my health care provider use a T4 Total test?

Total thyroxine tests are used to assess thyroid function and detect thyroid disorders, such as hyperthyroidism and hypothyroidism, after the thyroid stimulating hormone level has been found to be abnormal.

The thyroid gland produces T4 and another hormone called triiodothyronine. They aid in the regulation of the rate at which the body expends energy and are governed by a feedback system. TSH promotes the thyroid gland's synthesis and release of T4 and T3.

The majority of T4 and T3 in the blood is attached to protein, while just a small amount is free. Total T4, free T4, total T3, and free T3 can all be measured in blood testing. The total T4 test has been around for a long time, but it is influenced by the quantity of protein in the blood that can bind to the hormone. The active form of thyroxine, free T4, is unaffected by protein levels. Many people believe that the free T4 test is a more accurate reflection of thyroid hormone activity, and it has largely supplanted the total T4 test.

A Total T4 test can be used in conjunction with or after a TSH test, and occasionally with a free T3 test to:

  • Help diagnose the cause of hyperthyroidism and hypothyroidism by detecting too much or too little thyroid hormone.
  • Differentiate between thyroid disorders.
  • Assist in the diagnosis of pituitary diseases
  • Assist in the diagnosis of infertility in women
  • In an individual with a known thyroid condition, track the effectiveness of treatment.
  • Monitor patients with pituitary disease to ensure that their thyroid is still operating, and thyroid hormone medication should be monitored if it isn't.
  • Monitor patients with thyroid cancer whose tumors respond to TSH. TSH and T4 levels will be monitored on a regular basis to ensure that adequate thyroid hormone is being administered to maintain TSH low while keeping T4 high.

In the United States, babies are routinely tested for T4 and TSH levels to rule out congenital hypothyroidism, which can lead to mental retardation if left untreated.

Thyroid abnormalities can sometimes be detected using Total T4 and TSH, however professional opinions differ on who should be screened and when they should start.

Thyroid antibodies, as well as a Total T4 test, may be ordered if a health practitioner suspects someone has an autoimmune-related thyroid problem.

What does my T4 Total result mean?

In general, high total T4 levels suggest an overactive thyroid gland, while low total T4 levels suggest an underactive thyroid gland. The test results are not diagnostic in and of themselves, but they will urge the health care provider to conduct additional testing to determine the reason of the excess or deficiency.

A range of temporary and chronic thyroid disorders are linked to both decreased and increased total T4 levels. A pituitary gland issue could be indicated by low total T4 levels along with a low TSH level, or by high total T4 levels combined with a high TSH.

When thyroid tests are done to monitor treatment for thyroid or pituitary diseases, the results will tell the doctor whether the treatment is working and/or if a dose adjustment is required. People with hyperthyroidism, for example, have their total T4, total T3, and TSH levels examined on a regular basis while taking anti-thyroid medicines to ensure that the drugs are effective and to reduce doses if thyroid hormone levels fall too low. TSH and total T4 levels are monitored on a frequent basis in hypothyroid patients to ensure that the correct dose of thyroid hormone is being given to bring TSH levels back to normal.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


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Description: A T4 Free test is a blood test that measures thyroxine free levels in your blood’s serum to evaluate your thyroid’s health and to screen for, diagnose, and monitor thyroid disorders such as hypothyroidism.

Also Known As: Free T4 Test, Free Thyroxine Test, FT4 Test, T4F Test, T4 Free Test, Unbound T4 Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a T4 Free test ordered?

When a person exhibits symptoms of hyperthyroidism or hypothyroidism, a free T4 test may be administered, especially if the TSH test is abnormal.

Hyperthyroidism can cause the following signs and symptoms:

  • Heart rate has increased.
  • Anxiety
  • Loss of weight
  • Sleeping problems
  • Hand tremors
  • Weakness
  • Diarrhea
  • Visual disturbances, light sensitivity
  • Puffiness around the eyes, dryness, discomfort, and, in some cases, bulging of the eyes are all possible side effects.

Hypothyroidism can cause the following symptoms:

  • gaining weight
  • Skin that is dry
  • Constipation
  • Intolerance to the cold
  • Skin that is puffy
  • Hair loss
  • Fatigue
  • Women's menstrual irregularities

When a person is being treated for a thyroid problem, free T4 testing, along with other thyroid tests, may be requested on a regular basis.

Thyroid testing will most likely be ordered early and late in the pregnancy, as well as for a period after delivery, to monitor the mother and baby in pregnant women with thyroid abnormalities.

In the United States, thyroid hormone screening is routinely performed on babies as part of newborn screening programs.

What does a T4 Free blood test check for?

The thyroid gland, a small butterfly-shaped structure that lays on the windpipe towards the bottom of the throat, produces one of two primary hormones: thyroxine. Triiodothyronine is the other primary thyroid hormone, and together they help govern the rate at which the body utilizes energy. T4 in the blood is almost entirely linked to protein. The remaining portion is free and is the hormone's biologically active form. This test determines how much free T4 is present in the blood.

A feedback loop controls T4 production. The hypothalamus releases thyrotropin releasing hormone, which encourages the pituitary gland to generate and release thyroid-stimulating hormone when the amount of T4 in the blood drops. The thyroid gland is thus stimulated to produce and/or release more T4 as a result of TSH. TSH release is blocked as T4 content in the blood rises.

T4 accounts for over 90% of thyroid hormones. The thyroid gland releases accumulated T4 into circulation when the body requires it. T4 is either free or bound to protein in the blood. The amount of free T4 in the body is just about 0.1 percent of total T4. In the liver or other tissues, T4 is converted to T3. T3, like T4, is mainly attached to protein, however the physiologically active forms of T3 and T4 are the free versions. Free T3 in circulation is 4 to 5 times more active than free T4.

Dry skin, weight gain, cold intolerance, weariness, and irregular menstruation are among signs of hypothyroidism that occur when the thyroid gland does not produce enough T4 due to thyroid malfunction or insufficient TSH. Myxedema, or severe untreated hypothyroidism, can cause heart failure, convulsions, and coma. Hypothyroidism in children can slow growth and sexual development.

When the thyroid gland generates too much T4, the rate of a person's body functions increases, resulting in hyperthyroidism symptoms such as anxiety, increased heart rate, difficulty sleeping, weight loss, puffiness and dry itchy eyes, and hand tremors.

The most prevalent causes of thyroid dysfunction are connected to autoimmune illnesses. Hyperthyroidism is caused by Graves disease, while hypothyroidism is caused by Hashimoto thyroiditis. Thyroiditis, thyroid malignancy, and excessive or insufficient TSH production can all induce hyperthyroidism or hypothyroidism. By measuring free T4, the influence of these variables on thyroid hormone synthesis can be recognized and monitored.

Lab tests often ordered with a T4 Free test:

  • TSH
  • T3 Total
  • T3 Free
  • T4 Total
  • T3 Reverse
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies

Conditions where a T4 Free test is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

How does my health care provider use a T4 Free test?

Free thyroxine tests are used to assess thyroid function and detect thyroid disorders, such as hyperthyroidism and hypothyroidism, after the thyroid stimulating hormone level has been found to be abnormal.

The thyroid gland produces T4 and another hormone called triiodothyronine. They aid in the regulation of the rate at which the body expends energy and are governed by a feedback system. TSH promotes the thyroid gland's synthesis and release of T4 and T3.

The majority of T4 and T3 in the blood is attached to protein, while just a small amount is free. Total T4, free T4, total T3, and free T3 can all be measured in blood testing. The total T4 test has been around for a long time, but it is influenced by the quantity of protein in the blood that can bind to the hormone. The active form of thyroxine, free T4, is unaffected by protein levels. Many people believe that the free T4 test is a more accurate reflection of thyroid hormone activity, and it has largely supplanted the total T4 test.

A free T4 test can be used in conjunction with or after a TSH test, and occasionally with a free T3 test to:

  • Help diagnose the cause of hyperthyroidism and hypothyroidism by detecting too much or too little thyroid hormone.
  • Differentiate between thyroid disorders.
  • Assist in the diagnosis of pituitary diseases
  • Assist in the diagnosis of infertility in women
  • In an individual with a known thyroid condition, track the effectiveness of treatment.
  • Monitor patients with pituitary disease to ensure that their thyroid is still operating, and thyroid hormone medication should be monitored if it isn't.
  • Monitor patients with thyroid cancer whose tumors respond to TSH. TSH and T4 levels will be monitored on a regular basis to ensure that adequate thyroid hormone is being administered to maintain TSH low while keeping T4 high.

In the United States, babies are routinely tested for T4 and TSH levels to rule out congenital hypothyroidism, which can lead to mental retardation if left untreated.

Thyroid abnormalities can sometimes be detected using free T4 and TSH, however professional opinions differ on who should be screened and when they should start.

Thyroid antibodies, as well as a free T4 test, may be ordered if a health practitioner suspects someone has an autoimmune-related thyroid problem.

What does my T4 Free result mean?

In general, high free T4 levels suggest an overactive thyroid gland, while low free T4 levels suggest an underactive thyroid gland. The test results are not diagnostic in and of themselves, but they will urge the health care provider to conduct additional testing to determine the reason of the excess or deficiency.

A range of temporary and chronic thyroid disorders are linked to both decreased and increased free T4 levels. A pituitary gland issue could be indicated by low free T4 levels along with a low TSH level, or by high free T4 levels combined with a high TSH.

When thyroid tests are done to monitor treatment for thyroid or pituitary diseases, the results will tell the doctor whether the treatment is working and/or if a dose adjustment is required. People with hyperthyroidism, for example, have their free T4, free T3, and TSH levels examined on a regular basis while taking anti-thyroid medicines to ensure that the drugs are effective and to reduce doses if thyroid hormone levels fall too low. TSH and free T4 levels are monitored on a frequent basis in hypothyroid patients to ensure that the correct dose of thyroid hormone is being given to bring TSH levels back to normal.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


  • T3, Free [ 34429 ]
  • T4, Free [ 866 ]
  • TSH [ 899 ]

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • TSH [ 899 ]
  • Vitamin B12 (Cobalamin) [ 927 ]

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • Thyroid Peroxidase and Thyroglobulin Antibodies [ 7260 ]
  • TSH [ 899 ]
  • Vitamin B12 (Cobalamin) [ 927 ]
  • Vitamin B6 (Pyridoxal Phosphate ) [ 926 ]
     

  • CBC (includes Differential and Platelets) [ 6399 ]
  • Comprehensive Metabolic Panel (CMP) [ 10231 ]
  • Hemoglobin A1c (HgbA1C) [ 496 ]
  • Iron and Total Iron Binding Capacity (TIBC) [ 7573 ]
  • Lipid Panel with Ratios [ 19543 ]
  • QuestAssureD™ 25-Hydroxyvitamin D (D2, D3), LC/MS/MS [ 92888 ]
  • T3 Reverse (RT3), LC/MS/MS [ 90963 ]
  • T3 Total [ 859 ]
  • T3, Free [ 34429 ]
  • T4 (Thyroxine), Total [ 867 ]
  • T4, Free [ 866 ]
  • Thyroid Peroxidase and Thyroglobulin Antibodies [ 7260 ]
  • TRAb (TSH Receptor Binding Antibody) [ 38683 ]
  • TSH [ 899 ]
  • TSI (Thyroid Stimulating Immunoglobulin) [ 30551 ]
  • Vitamin B12 (Cobalamin) [ 927 ]
  • Vitamin B6 (Pyridoxal Phosphate ) [ 926 ]
     

Description: Thyroid Peroxidase and Thyroglobulin are blood tests used to detect thyroid antibodies to check for thyroid autoimmune disorders.

Also Known As: Thyroid Autoantibodies Test, Antithyroid Antibodies Test, Thyroid Peroxidase Antibody Test, Thyroperoxidase Antibody Test, TPO Test, Anti-TPO Test, Antithyroglobulin Antibody Test, TgAb Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a Thyroid Peroxidase and Thyroglobulin Antibodies test ordered?

When a person has irregular TSH and/or free T4 test results, symptoms of low or high thyroid hormone levels, or the appearance of a goiter, testing may be performed, especially if the reason is considered to be an autoimmune condition.

Hypothyroidism can produce a variety of symptoms, including:

  • Gaining weight
  • Fatigue
  • Skin that is dry
  • Hair loss
  • Cold intolerance
  • Constipation

Hyperthyroidism can produce symptoms such as:

  • Sweating
  • Heart rate that is quite fast
  • Anxiety
  • Tremors
  • Fatigue
  • Sleeping problems 
  • Sudden weight loss
  • Eyes that protrude

If a pregnant woman has a known autoimmune thyroid illness, or if another autoimmune disorder is suspected, one or more thyroid antibodies may be ordered early in the pregnancy and again at the end. These tests are performed to see if the newborn is at risk for thyroid problems. Thyroid antibodies can pass the placenta, causing hypothyroidism or hyperthyroidism in a newborn or developing kid.

Thyroid antibody testing may also be recommended if a person with another autoimmune condition has thyroid dysfunction symptoms and/or has reproductive problems that a healthcare provider suspects are caused by antibodies.

What does a Thyroid Peroxidase and Thyroglobulin Antibodies blood test check for?

Thyroid antibodies are antibodies that form when an individual's immune system incorrectly attacks the thyroid gland or thyroid protein components, causing chronic thyroid inflammation, tissue destruction, and/or thyroid function disruption. Specific thyroid antibodies in the blood are detected and quantified using laboratory techniques.

The thyroid gland is a tiny, butterfly-shaped gland in the throat that rests flat against the windpipe. Thyroxine and triiodothyronine, the two key hormones it generates, are critical in regulating the pace at which the body uses energy. Thyroid stimulating hormone stimulates the thyroid to generate T4 and T3 as needed by the body's feedback system. This mechanism aids in the maintenance of a reasonably constant level of thyroid hormones in the blood. Thyroid antibodies can cause chronic diseases and autoimmune disorders linked with hypothyroidism or hyperthyroidism, such as Graves disease or Hashimoto thyroiditis, when they interfere with this process.

Thyroid antibody testing includes the following:

  • Thyroid peroxidase antibody
  • Thyroglobulin antibody

Lab tests often ordered with a Thyroid Peroxidase and Thyroglobulin Antibodies test:

  • T3 Free
  • T3 Total
  • T4 Free
  • T4 Total
  • T3 Reverse
  • T3 Uptake
  • TSH

Conditions where a Thyroid Peroxidase and Thyroglobulin Antibodies test is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

Commonly Asked Questions:

How does my health care provider use a Thyroid Peroxidase and Thyroglobulin Antibodies test?

Thyroid antibodies, such as thyroid peroxidase antibody, are tested to assist diagnose and differentiate autoimmune thyroid disease from other types of thyroid failure. Thyroid antibodies form when a person's immune system mistakenly targets thyroid gland or thyroid protein components, causing chronic thyroid inflammation, tissue destruction, and/or thyroid function disruption.

To aid in the diagnosis and/or monitoring of an autoimmune thyroid condition, one or more of the following tests may be used:

  • Thyroid peroxidase antibody, an antibody that targets thyroid peroxidase enzyme in the thyroid gland, can be seen in Graves disease and Hashimoto thyroiditis.
  • Thyroglobulin antibody is an antibody that targets thyroglobulin, the thyroid hormone's storage form.

These tests may be conducted to determine the reason of an enlarged thyroid or other symptoms linked to low or high thyroid hormone levels. When other thyroid test findings, such as total or free T3, free T4, and/or TSH, indicate thyroid dysfunction, testing may be done as a follow-up.

A thyroid antibody test or several thyroid antibody tests may be conducted to see if a person with an autoimmune disorder is at risk of thyroid dysfunction. Disorders like rheumatoid arthritis, systemic lupus erythematosus, and pernicious anemia can cause this.

A thyroglobulin test may be used to monitor someone who is being treated for thyroid cancer. The thyroglobulin antibody test is utilized in this scenario to see if the antibody is present in the person's blood and will interfere with the thyroglobulin level test.

What do my Thyroid Antibodies test results mean?

Negative test results show that thyroid antibodies were not detected in the blood at the time of testing, implying that symptoms are caused by anything other than autoimmune disease. However, antibodies are absent in a small number of persons with autoimmune thyroid disease. Repeat testing may be done at a later date if it is suspected that the antibodies will develop over time, as with several autoimmune illnesses.

Thyroid antibodies can be identified in a range of thyroid and autoimmune conditions, including thyroid cancer, type 1 diabetes, rheumatoid arthritis, pernicious anemia, and autoimmune collagen vascular diseases, with mild to moderately high levels.

Thyroid autoimmune disorders such as Hashimoto thyroiditis and Graves disease are usually associated with significantly elevated amounts.

Thyroid antibodies, in general, indicate the presence of an autoimmune thyroid illness, and the higher the level, the more likely it is. Antibody levels that grow over time may be more relevant than steady levels because they may suggest an increase in the severity of autoimmune illness. All of these antibodies can increase the risk of hypothyroidism or hyperthyroidism in a growing baby or infant if they are present in a pregnant mother.

If a person with thyroid cancer has thyroglobulin antibodies, the testing for thyroglobulin levels may be hampered. This could suggest that the thyroglobulin test can't be utilized as a tumor marker or to track a person's thyroid cancer progression. The presence of thyroglobulin antibodies has little effect on some testing procedures, including mass spectrometry. The thyroglobulin test can be utilized as a tumor marker when tested in these methods, regardless of whether or not thyroglobulin antibodies are present. If a method is utilized that is impacted by thyroglobulin antibodies, the antibodies' levels can be used as a tumor marker to monitor thyroid cancer. If they first remain high or fall low but then rise over time, the treatment was ineffective and the malignancy is likely to continue or recur. If the levels are dropping and/or have dropped to low or undetectable levels, the therapy is more likely to have been successful in eradicating the malignancy.

Thyroid antibodies can be found in a small percentage of patients who are otherwise healthy. The incidence of these antibodies is higher in women, increases with age, and implies an increased risk of developing thyroid illness in the future for thyroid peroxidase antibodies. If a person has a thyroid antibody but no obvious thyroid disease, the healthcare professional will monitor the person's health over time. While the majority of people will never have thyroid problems, a small percentage will.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


TRAb (TSH Receptor Binding Antibody) 

TBII (Thyrotropin Binding Inhibit Immunoglobulin)

Clinical Significance

Measurement of TBII is used to diagnose and manage Graves' Disease, Neonatal Hypothyroidism, and Postpartum Thyroid Dysfunction.

Alternative Name(s) 

Thyroid Stimulating Hormone (TSH) Receptor Antibody,Thyrotropin Receptor Antibody,TSH Receptor Blocking Antibody,Thyrotropin-Binding Inhibitory Immunoglobulin

 

 


Most Popular

Description: A TSH test is a blood test that measures thyroid stimulating hormone levels in your blood’s serum and is used to screen for and monitor treatment of thyroid disorders such as hypothyroidism and hyperthyroidism.

Also Known As: Thyroid Stimulating Hormone Test, Thyrotropin Test, TSH test, Thyroid Test, TSH Screen Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a TSH test ordered?

When a person has symptoms of hyperthyroidism or hypothyroidism, or an enlarged thyroid gland, a doctor may order a TSH test.

Hyperthyroidism can cause the following signs and symptoms:

  • Heart rate has increased.
  • Anxiety
  • Loss of weight
  • Sleeping problems
  • Hand tremors.
  • Weakness
  • Diarrhea
  • Visual disturbances, light sensitivity
  • Puffiness around the eyes, dryness, discomfort, and, in some cases, bulging of the eyes are all possible side effects.

Hypothyroidism can cause the following signs and symptoms:

  • gaining weight
  • Skin that is dry
  • Constipation
  • Intolerance to the cold
  • Skin that is puffy
  • Hair loss is a common problem.
  • Fatigue
  • Women's menstrual irregularities

When a person is being treated for a thyroid disease, TSH may be ordered at regular intervals. The American Thyroid Association suggests waiting 6-8 weeks after changing a person's thyroid medication dose before testing their TSH level again.

In the United States, TSH screening is routinely performed on newborns shortly after birth as part of each state's newborn screening program.

What does a TSH blood test check for?

The pituitary gland, a small structure beneath the brain and beyond the sinus cavities, produces thyroid-stimulating hormone. TSH causes thyroxine and triiodothyronine to be released into the bloodstream by the thyroid gland. These thyroid hormones aid in the regulation of the body's energy usage. This test determines how much TSH is present in the blood.

The feedback mechanism that the body utilizes to maintain consistent quantities of thyroid hormones in the blood includes TSH and its regulatory hormone, thyrotropin releasing hormone, which comes from the hypothalamus. TSH synthesis by the pituitary gland increases as thyroid hormone concentrations fall. TSH stimulates the thyroid gland, a small butterfly-shaped gland that lays flat against the windpipe at the base of the throat, to produce and release T4 and T3. Thyroid production turns on and off to maintain generally steady levels of thyroid hormones in the blood when all three organs are operating regularly.

When the thyroid produces excessive amounts of T4 and T3, the affected person may have hyperthyroidism symptoms such as high heart rate, weight loss, agitation, hand tremors, itchy eyes, and difficulty sleeping. The most prevalent cause of hyperthyroidism is Graves disease. It is a chronic autoimmune condition in which the immune system creates antibodies that mimic TSH, causing the thyroid hormone to be produced in excessive levels. As a result, the pituitary gland may produce less TSH, resulting in a low blood level.

Weight gain, dry skin, constipation, cold intolerance, and weariness are all symptoms of hypothyroidism, a condition in which the thyroid produces fewer thyroid hormones. In the United States, Hashimoto thyroiditis is the most prevalent cause of hypothyroidism. It's an autoimmune disease in which the immune system attacks the thyroid, causing inflammation and destruction as well as the generation of autoantibodies. The thyroid generates low levels of thyroid hormone in Hashimoto thyroiditis. The pituitary gland may create more TSH, resulting in a high blood level.

TSH values, on the other hand, do not necessarily indicate or predict thyroid hormone levels. TSH is produced abnormally in some persons and does not work properly. Despite having normal or modestly increased TSH values, they frequently develop hypothyroidism. Thyroid hormone levels can be high or low in a variety of thyroid illnesses, regardless of the amount of TSH in the blood.

TSH levels may be elevated or lowered in rare cases due to pituitary dysfunction. In addition to pituitary dysfunction, an issue with the hypothalamus can cause hyperthyroidism or hypothyroidism.

Lab tests often ordered with a TSH test:

  • T3 Free
  • T3 Total
  • T4 Free
  • T4 Total
  • T3 Reverse
  • T3 Uptake
  • Thyroid Peroxidase
  • Thyroglobulin Antibodies
  • Thyroid Panel

Conditions where a test TSH is recommended:

  • Hyperthyroidism
  • Hypothyroidism
  • Hashimotos
  • Graves’ Disease
  • Autoimmune Diseases
  • Thyroid Cancer

Commonly Asked Questions:

How does my health care provider use a TSH test?

Thyroid function and/or symptoms of a thyroid problem, such as hyperthyroidism or hypothyroidism, are frequently assessed with the thyroid-stimulating hormone test.

The pituitary gland, a small structure beneath the brain and beyond the sinus cavities, produces TSH. It's a part of the body's feedback system that keeps the thyroid hormones thyroxine and triiodothyronine in check and helps regulate the pace at which the body burns calories.

TSH tests are typically ordered in conjunction with or before a free T4 test. A free T3 test and thyroid antibodies are two further thyroid tests that can be ordered. TSH, free T4, and free T3 are sometimes ordered as part of a thyroid panel.

TSH is used to:

  • Diagnose a thyroid issue in a patient who is experiencing symptoms.
  • Check newborns for an underactive thyroid.
  • Monitor thyroid replacement therapy.
  • Monitor treatment of hyperthyroidism that involves medication.
  • Assist women in diagnosing and monitoring infertility issues.
  • Assist in determining the pituitary gland's function
  • Screen adults for thyroid issues and diseases.

What does my TSH blood test result mean?

A high TSH level could indicate that:

  • The person being examined has an underactive thyroid gland that isn't responding well to TSH stimulation owing to acute or chronic thyroid dysfunction.
  • If a person has hypothyroidism or has had their thyroid gland removed, the dose of thyroid hormone replacement medicine may need to be changed.
  • A patient with hyperthyroidism is taking too much anti-thyroid medication, and the dosage needs to be reduced.
  • There is a problem with the pituitary gland, such as a tumor that causes TSH levels to be out of control.

A low TSH level could imply the following:

  • An overactive thyroid gland
  • Thyroid hormone prescription taken in excess by patients being treated for an underactive thyroid gland.
  • Inadequate medication in an individual being treated for hyperthyroidism; nevertheless, after successful anti-thyroid treatment, TSH production may take a time to recover. This is why the American Thyroid Association recommends testing for thyroid hormones as well as TSH levels throughout treatment.
  • The pituitary gland has been damaged, preventing it from releasing enough TSH.

An abnormal TSH result, whether high or low, suggests an excess or deficiency in the quantity of thyroid hormone available to the body, but does not pinpoint the cause for the abnormal result. Additional testing is frequently performed after an abnormal TSH test result to determine the reason of the increase or decrease.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


TSI stands for thyroid stimulating immunoglobulin. TSI tells the thyroid gland to swell and release excess amounts of thyroid hormone into the blood.

Description: A Vitamin B12 test is a blood test that measures the level of Vitamin B12 in the blood’s serum and is used to detect Vitamin B12 deficiency.

Also Known As:  B12 Test, Cobalamin Test, Vitamin B12 test, Serum B12 Test 

Collection Method: Blood Draw 

Specimen Type: Serum 

Test Preparation: No preparation required. 

When is a Vitamin B12 test ordered?  

When a complete blood count and/or blood smear, performed as part of a health checkup or anemia evaluation, reveal a low red blood cell count with the presence of big RBCs, vitamin B12 levels may be ordered. A high mean corpuscular volume implies that the RBCs have grown in size. 

When a person exhibits the following signs and symptoms of a deficit, testing for B12 levels may be necessary: 

  • Diarrhea 
  • Dizziness 
  • Muscle weakness, fatigue 
  • Appetite loss. 
  • Skin that is pale 
  • Irregular heartbeats, rapid heart rate 
  • Breathing problems 
  • Tongue and mouth ache 
  • In the feet, hands, arms, and legs, there is tingling, numbness, and/or burning 
  • Confusion or obliviousness 
  • Paranoia 

When a person is at risk of deficiency, such as those with a history of malnutrition or a condition associated to malabsorption, B12 tests may be required. 

Individuals being treated for malnutrition or a B12 or folate deficit may have these tests done on a frequent basis to see how effective their treatments are. This could be part of a long-term therapy plan for people who have a disease that causes chronic deficiency.  

What does a Vitamin B12 blood test check for? 

Vitamin B12 is a member of the vitamin B complex. It is required for the creation of normal red blood cells, tissue and cell healing, and the synthesis of DNA, the genetic material in cells. Vitamin B12 is a nutrient that the body cannot make and must be obtained through the diet. 

Vitamin B12 deficiency is detected by measuring vitamin B12 in the liquid portion of the blood. 

A B12 deficiency can cause macrocytic anemia, which is characterized by red blood cells that are bigger than normal. Megaloblastic anemia is a kind of macrocytic anemia marked by the generation of fewer but larger RBCs known as macrocytes, as well as cellular abnormalities in the bone marrow. Reduced white blood cell and platelet count are two other test results linked to megaloblastic anemia. 

B12 is also necessary for nerve function, and a lack of it can induce neuropathy, which causes tingling and numbness in the hands and feet of those who are affected. 

B12 deficiency is most commonly caused by a lack of vitamin B12 in the diet or supplements, insufficient absorption, or an increased requirement, such as during pregnancy. 

Lab tests often ordered with a Vitamin B12 test: 

  • Folate 
  • Methylmalonic Acid (MMA) 
  • Homocysteine 
  • Vitamin B1 
  • Vitamin B2 
  • Vitamin B3 
  • Vitamin B5 
  • Vitamin B6 
  • Vitamin B7 
  • Rheumatoid factor 

Conditions where a Vitamin B12 test is recommended:

  • Vitamin B12 Deficiency 
  • Pernicious Anemia 
  • Nerve Damage 
  • Malabsorption 
  • Malnutrition 

How does my health care provider use a Vitamin B12 test? 

Vitamin B12 and folate are frequently used in conjunction to detect deficiencies and to aid in the diagnosis of anemias such as pernicious anemia, an inflammatory condition that inhibits B12 absorption. 

B12 and folate are two vitamins that the body cannot generate and must be obtained from the diet. They are essential for the creation of normal red blood cells, tissue and cell repair, and the synthesis of DNA, the genetic material in cells. B12 is required for normal nerve function. 

B12 and folate tests can also be used to assess someone who is experiencing mental or behavioral changes, especially in the elderly. A B12 test can be ordered with or without folate, as well as with other screening laboratory tests like a complete blood count, comprehensive metabolic panel, antinuclear antibody, C-reactive protein, and rheumatoid factor to help determine why a person is exhibiting signs and symptoms of a nerve condition. 

B12 and folate tests can also be performed in conjunction with a variety of other tests to assess a person's overall health and nutritional status if they have signs and symptoms of substantial malnutrition or dietary malabsorption. People with alcoholism, liver disease, stomach cancer, or malabsorption diseases including celiac disease, inflammatory bowel disease, or cystic fibrosis may fall into this category. 

Testing may be performed to assess the success of treatment in patients with known B12 and folate deficits. This is especially true for people who cannot absorb B12 and/or folate effectively and must be treated for the rest of their lives. 

Folate levels in the blood's serum might fluctuate depending on a person's recent diet. Because red blood cells contain 95 percent of circulating folate, a test to evaluate folate levels inside RBCs could be employed instead of or in addition to the serum test. Some doctors believe that the RBC folate test is a better predictor of long-term folate status and is more clinically useful than serum folate, however there is no consensus on this. 

Homocysteine and methylmalonic acid are two more laboratory tests that can be used to detect B12 and folate deficits. In B12 deficiency, both homocysteine and MMA are high, whereas in folate deficit, only homocysteine, not MMA, is elevated. This distinction is critical because treating anemia with folate treats the anemia but not the brain damage, which may be irreparable. 

What do my Vitamin B12 test results mean? 

Normal B12 and folate levels may indicate that a person does not suffer from a deficiency and that the signs and symptoms they are experiencing?are caused by something else. Normal levels, on the other hand, may indicate that a person's stored B12 and/or folate has not yet been depleted. 

A health practitioner may order a methylmalonic acid test as an early sign of B12 deficiency if a B12 level is normal but a deficiency is still suspected. 

A low B12 and/or folate level in a person with signs and symptoms implies a deficiency, although it does not always indicate the severity of the anemia or related neuropathy. Additional tests are frequently performed to determine the source of the deficit. Low B12 or folate levels can be caused by a variety of factors. 

Dietary folate or B12 deficiency, which?is uncommon in the United States. It can be evident in people who are malnourished in general and vegans who do not eat any animal products. Folate deficiency has become extremely rare since the development of fortified cereals, breads, and other grain products. 

Both B12 and folate deficits can be caused by diseases that prevent them from being absorbed in the small intestine. These may include the following: 

  • Pernicious anemia 
  • Celiac disease 
  • Crohn's disease and ulcerative colitis are examples of inflammatory bowel disease. 
  • Bacterial overgrowth or the presence of parasites in the intestines, such as tapeworms 
  • Long-term usage of antacids or H2 proton pump inhibitors reduces stomach acid production. 
  • Absorption can be considerably reduced by surgery that removes part of the stomach or the intestines, such as gastric bypass. 
  • Insufficiency of the pancreas 
  • Chronic alcoholism or heavy drinking 
  • Some treatments, such as metformin, omeprazole, methotrexate, or anti-seizure medications like phenytoin, are used. 
  • Increased requirements for healthy fetal development, all pregnant women require an increased amount of folate and are advised to consume 400 micrograms of folic acid every day. The need for folate is higher in those who have cancer that has spread or who have chronic hemolytic anemia. 
  • Smoking 

If a person is being treated for a B12 or folate deficit with supplements, normal or higher findings suggest that the treatment is working. 

High amounts of B12 are uncommon, and they aren't routinely evaluated clinically. If a person has a condition such chronic myeloproliferative neoplasm, diabetes, heart failure, obesity, AIDS, or severe liver disease, their vitamin B12 level may be elevated. High B12 levels can also be caused by using estrogens, vitamin C, or vitamin A. 

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.


Vitamin B6 is a cofactor in many metabolic pathways including heme synthesis. Vitamin B6 deficiency may be observed in patients with metabolic disorders, secondary to therapeutic drug use, or alcoholism. Deficiency affects the function of the immune system.

Brief Description: A Vitamin D test is a blood test used to determine if you have a Vitamin D deficiency and to monitor Vitamin D levels if you are on supplementation.

Also Known As: Ergocalciferol Test, Vitamin D2 Test, Cholecalciferol Test, Vitamin D3 Test, Calcidiol Test, 25-hydroxyvitamin D Test, Calcifidiol Test, 25-hydroxy-vitamin D Test, Vitamin D Total Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: Fasting preferred, but not required.

When is a Vitamin D test ordered?

When calcium levels are inadequate and/or a person exhibits symptoms of vitamin D deficiency, such as rickets in children and bone weakening, softness, or fracture in adults, 25-hydroxyvitamin D is frequently ordered to rule out a vitamin D deficit.

When a person is suspected of having a vitamin D deficiency, the test may be requested. Vitamin D deficiency is more common in older folks, people who are institutionalized or homebound and/or have minimal sun exposure, people who are obese, have had gastric bypass surgery, and/or have fat malabsorption. People with darker skin and breastfed babies are also included in this category.

Before starting osteoporosis medication, 25-hydroxyvitamin D is frequently requested.

What does a Vitamin D blood test check for?

Vitamin D is a group of chemicals that are necessary for the healthy development and growth of teeth and bones. The level of vitamin D in the blood is determined by this test.

Vitamin D is tested in the blood in two forms: 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D. The primary form of vitamin D found in the blood is 25-hydroxyvitamin D, which is a relatively inactive precursor to the active hormone 1,25-dihydroxyvitamin D. 25-hydroxyvitamin D is routinely evaluated to assess and monitor vitamin D status in humans due to its longer half-life and higher concentration.

Endogenous vitamin D is created in the skin when exposed to sunshine, whereas exogenous vitamin D is taken through foods and supplements. Vitamin D2 and vitamin D3 have somewhat different molecular structures. Fortified foods, as well as most vitamin preparations and supplements, include the D2 form. The type of vitamin D3 produced by the body is also used in some supplements. When the liver and kidneys convert vitamin D2 and D3 into the active form, 1,25-dihydroxyvitamin D, they are equally effective.

Some tests may not differentiate between the D2 and D3 forms of vitamin D and just report the total result. Newer methods, on the other hand, may record D2 and D3 levels separately and then sum them up to get a total level.

Vitamin D's major function is to assist balance calcium, phosphorus, and magnesium levels in the blood. Vitamin D is necessary for bone growth and health; without it, bones become fragile, misshapen, and unable to mend themselves properly, leading to disorders such as rickets in children and osteomalacia in adults. Vitamin D has also been proven to influence the growth and differentiation of a variety of other tissues, as well as to aid in immune system regulation. Other illnesses, such as autoimmune and cancer, have been linked to vitamin D's other roles.

According to the Centers for Disease Control and Prevention, two-thirds of the US population has adequate vitamin D, while one-quarter is at risk of inadequate vitamin D and 8% is at risk of insufficiency, as defined by the Institute of Medicine's Dietary Reference Intake.

The elderly or obese, persons who don't receive enough sun exposure, people with darker skin, and people who take certain drugs for lengthy periods of time are all at risk of insufficiency. Adequate sun exposure is usually defined as two intervals of 5-20 minutes each week. Vitamin D can be obtained through dietary sources or supplements by people who do not get enough sun exposure.

This test has 3 Biomarkers

  • Vitamin D Total which is a combined measurement of Vitamin D, 25-Oh, D2 and Vitamin 25-Oh, D3
  • Vitamin D, 25-Oh, D2 which is a measurement of ergocalciferol Vitamin D, which is Vitamin D obtained through plant sources. 
  • Vitamin D, 25-Oh, D3 which is a measurement of cholecalciferol Vitamin D, which is Vitamin D obtained through animal sources.

Lab tests often ordered with a Vitamin D test:

  • Complete Blood Count
  • CMP
  • Iron and TIBC
  • Calcium
  • Phosphorus
  • PTH
  • Magnesium

Conditions where a Vitamin D test is recommended:

  • Kidney Disease
  • Osteoporosis
  • Lymphoma
  • Cystic Fibrosis
  • Autoimmune Disorders
  • Celiac Disease
  • Malabsorption
  • Malnutrition

Commonly Asked Questions:

How does my health care provider use a Vitamin D test?

Determine whether a deficit or excess of vitamin D is causing bone weakening, deformity, or improper calcium metabolism.

Because PTH is required for vitamin D activation, it can aid in diagnosing or monitoring problems with parathyroid gland function.

Because vitamin D is a fat-soluble vitamin that is absorbed from the intestine like a fat, it can help monitor the health of people with conditions that interfere with fat absorption, such as cystic fibrosis and Crohn's disease.

People who have had gastric bypass surgery and may not be able to absorb adequate vitamin D should be closely monitored.

When vitamin D, calcium, phosphorus, and/or magnesium supplementation is suggested, it can help assess the success of the treatment.

What do my Vitamin D results result mean?

Despite the fact that vitamin D techniques differ, most laboratories use the same reference intervals. Because toxicity is uncommon, researchers have focused on the lower limit and what cut-off for total 25-hydroxyvitamin D shortage implies.

A low blood level of 25-hydroxyvitamin D could indicate that a person isn't getting enough sunlight or dietary vitamin D to meet his or her body's needs, or that there's an issue with absorption from the intestines. Seizure medications, notably phenytoin, might occasionally interfere with the liver's generation of 25-hydroxyvitamin D.

Vitamin D insufficiency has been linked to an increased risk of some malignancies, immunological illnesses, and cardiovascular disease.

Excessive supplementation with vitamin pills or other nutritional supplements frequently results in a high level of 25-hydroxyvitamin D.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.



Did you know that an estimated 20 million Americans have some form of thyroid disease?

Among the different types of thyroid disorders, hypothyroidism is the most common. Most of the time, hypothyroidism is mild and causes few (if any) major symptoms.

Left untreated, however, it can worsen over time and lead to other complications with your health.

Is there a history of thyroid disease in your family? Have you noticed symptoms of hypothyroidism in your body? Are you wondering how to test for hypothyroidism?

In this post, we'll briefly discuss some common hypothyroidism symptoms and risk factors. Then we'll reveal 18 different lab tests you can order to test for hypothyroidism.

Read on to learn more—your health depends on it!

What Is Hypothyroidism?

Before we dive into screening and testing, let's first define hypothyroidism.

Your thyroid is a butterfly-shaped gland located in your throat. As one of your body's endocrine glands, it's responsible for producing certain hormones.

Among other functions, your thyroid regulates your metabolism, your heart rate, and your body temperature. If your thyroid isn't active enough to produce the hormones your body needs, these functions will begin to slow down.

When this happens, it's known as hypothyroidism (underactive thyroid).

Hypothyroidism Symptoms

The symptoms of hypothyroidism vary depending on the severity of the hormonal deficiency. Problems tend to develop very slowly, usually over a number of years.

At first, you may hardly notice the symptoms of hypothyroidism. You may attribute symptoms like fatigue and weight gain to getting older.

But as your metabolism continues to slow down, you may soon develop more obvious problems. Hypothyroidism signs and symptoms may include:

  • Fatigue
  • Increased sensitivity to cold
  • Constipation
  • Dry skin
  • Weight gain
  • Puffy face
  • Hoarseness
  • Muscle weakness
  • Elevated blood cholesterol level
  • Muscle aches, tenderness, and stiffness
  • Pain, stiffness, or swelling in your joints
  • Heavier or irregular menstrual periods
  • Thinning hair
  • Slowed heart rate
  • Depression
  • Impaired memory
  • Enlarged thyroid gland (goiter)

Children and teens who develop hypothyroidism generally have the same symptoms as adults. But they may also experience:

  • Poor growth, resulting in short stature
  • Delayed development of permanent teeth
  • Delayed puberty
  • Poor mental development

These symptoms are often vague and don't outwardly appear to be related. If you notice some of these symptoms over an extended period of time, it's a good idea to get tested.

The sooner you do, the sooner you can get diagnosed and receive the treatment you need.

Risk Factors for Hypothyroidism

Although anyone can develop hypothyroidism, you're at an increased risk if you:

  • Are a woman
  • Are older than 60
  • Have a family history of thyroid disease
  • Have an autoimmune disease, such as type 1 diabetes or celiac disease
  • Have been treated with radioactive iodine or anti-thyroid medications
  • Received radiation to your neck or upper chest
  • Have had thyroid surgery (partial thyroidectomy)
  • Have been pregnant or delivered a baby within the past six months

Keep in mind that these are generalizations and that hypothyroidism can affect anyone of any age.

How to Test for Hypothyroidism: 18 Key Lab Tests

Now that you understand hypothyroidism symptoms and risk factors, how do you test for it?

It will likely require a combination of tests to determine your hormone levels and other factors that indicate a thyroid disorder. To make things easier, here's a list of 18 tests you can order to measure how active (or underactive) your thyroid may be.

1. TSH

TSH stands for "thyroid-stimulating hormone." This is the first place to start when you're evaluating the health of your thyroid.

TSH is produced in your pituitary gland inside your brain. This is the "master gland" that controls the level of hormones your thyroid produces and releases into your body.

This test measures how much TSH is in your bloodstream. Normal levels are anywhere between 0.4 and 4.0 milliunits per liter (mU/L). If your TSH levels are too high (over 4.0), it means your thyroid is underactive and could be a sign of hypothyroidism.

2. T3 Reverse, LC/MS/MS

Your body uses part of the T4 thyroid hormone to produce Reverse T3 (rT3). This serves as an inactive form of thyroid hormone.

Reverse T3 may attach to the Free T3 receptors, which slows down your metabolic processes. Some studies suggest that high levels of rT3 can contribute to acute major depressive disorder.

Ordering a Reverse T3 test can help you determine if your body is effectively converting T4 into the proper amount of Free T3 and rT3. Normal levels are below 250 pg/ml (10 to 24 ng/dL).

3. T3 Total

This test measures blood levels of the thyroid hormone T3 (triiodothyronine). Some T3 is directly produced in the thyroid gland, but most T3 is the result of chemical conversion from T4.

Bound T3 attaches to hormones that help to transport it throughout the body. Free T3 circulates through the bloodstream unattached.

T3 total test measures both the bound and free types of T3 in your body. A normal result range is 100-200 nanograms per deciliter (ng/dL).

4. T3, Free

As mentioned above, there are two types of T3 inside your body. Total T3 may be affected by protein levels and your body's protein binding ability, but the Free T3 hormone is not.

While a Total T3 test measures both types, this test only measures your Free T3 levels. Either test (Free T3 or Total T3) can be used to assess your current hormone levels. The normal range is for Free T3 is 260-480 pg/dL or 4-7.4 pmol/L.

Keep in mind that any of these tests on their own won't be enough to make a diagnosis. By studying your TSH, T4, and T3 levels, your doctor will be able to determine if you have hypothyroidism.

5. T4 (Thyroxine), Total

T4 is the main thyroid hormone your body produces. Also called thyroxine, it plays an important part in regulating your weight, body temperature, metabolism, and mood.

In a healthy thyroid, some T4 also converts into T3 to be used by the body. If you have hypothyroidism, this process can be interrupted. A high TSH level combined with low levels of T4 may signal hypothyroidism.

Total T4 test is an essential part of assessing and diagnosing an underactive thyroid.

6. T4 Free (FT4)

Approximately 99% of T4 hormones are bound. This means they're attached to proteins that prevent them from entering the body's tissues.

Since most T4 is converted into T3, Free T4 is the more important hormone to measure. Any changes the could indicate hypothyroidism will show up first in T4.

The normal range for Free T4 is 0.8 to 2.8 nanograms per deciliter (ng/dL). You can find out your levels with a T4 Free test.

7. Thyroglobulin Antibodies (TgAb)

One of the most common causes of hypothyroidism is an autoimmune disease known as Hashimoto's.

With Hashimoto's, your body mistakes your healthy, functioning thyroid for a "foreign" invader. It then launches an attack against the thyroid in the form of antibodies.

If you're healthy and your thyroid is functioning normally, you'll have no measurable amount of TgAb in your blood. Elevated levels in a TgAb test are a possible sign of an autoimmune version of hypothyroidism.

8. Thyroid Peroxidase Antibodies (TPO)

Thyroid peroxidase (TPO) is an enzyme found in your thyroid gland. It plays an important role in the normal production of thyroid hormones.

Similar to the thyroglobulin antibodies, there's no reason for your body to produce antibodies against this enzyme. The presence of TPO antibodies in your blood signals an autoimmune attack on your thyroid.

TPO test detects the level of antibodies against TPO in the blood. The normal range is 0-35 IU/mL.

9. TRAb (TSH Receptor Binding Antibody)

TRAb is an antibody to the thyroid cell receptor for thyroid-stimulating hormone (TSH).

It's found in most patients with Graves' Disease and is a primary cause of hyperthyroidism (overactive thyroid). Normal levels fall between 0.0−1.75 units/L.

What if you have some symptoms that seem hyper and some that seem hypo? This test can help rule out hyperthyroidism and bring you one step closer to the right diagnosis.

10. TSI (Thyroid Stimulating Immunoglobulin)

TSI stands for thyroid-stimulating immunoglobulin. It signals the thyroid gland to swell and release excessive amounts of thyroid hormone into the bloodstream.

TSIs mimic the action of TSH, causing over-secretion of T3 and T4. The TSI level will be abnormally high in persons with hyperthyroidism (Grave's Disease). Normal levels are less than 1.3 or 130%.

TSI test will measure this hormone in your blood and help your doctor assess your thyroid function.

11. CBC (includes Differential and Platelets)

CBC stands for complete blood count. It's the most commonly ordered blood test to evaluate your overall health.

This test measures the cells that make up your blood, including red and white blood cells as well as hemoglobin, hematocrit, and platelets. Abnormally high or low levels of any of these components can signal an underlying medical condition.

Be sure to include a CBC test with any specific thyroid tests you order. This will provide your doctor with "the whole picture" of what's going on inside your body.

12. Comprehensive Metabolic Panel (CMP)

One of the main symptoms of hypothyroidism is a sluggish metabolism. A CMP test provides vital information about your body's metabolism and chemical balance.

This test measures glucose, electrolytes, calcium, and protein levels in your blood. Like abnormalities in the CBC test, unusually high or low results means your body isn't performing at an optimal level.

The results of this common test can help your doctor determine how fast or slow your metabolism is functioning.

13. Hemoglobin A1c (HgbA1C)

This hemoglobin A1c test reveals your average blood sugar levels over the past few months. It's commonly ordered to help diagnose diabetes.

What does this have to do with thyroid function? Both diseases indicate dysfunction within the endocrine system. Research has found that thyroid disorders can have a major impact on glucose control.

Ordering a HgbA1C test will let you know if your blood sugar is within the normal limits (between 4%-5.6%)

14. Iron and Total Iron Binding Capacity (TIBC)

Diabetes isn't the only disease linked with hypothyroidism.

Anemia is a frequently occurring clinical condition that accompanies thyroid disease. In fact, prolonged iron deficiency can contribute to the development of hypothyroidism.

The TIBC test measures the amount of iron that would appear in blood if all the transferrin were saturated with iron. This reveals if you're anemic, which could facilitate a diagnosis.

15. Lipid Panel with Ratios

Hypothyroidism can contribute to elevated cholesterol levels.

When your body isn't producing enough thyroid hormones, it doesn't have the tools it needs to efficiently break down and remove cholesterol.

lipid panel test will measure your body's levels of "good" cholesterol (HDL), as well as the "bad" cholesterol (LDL). Higher than normal levels (less than 200 milligrams per deciliter) could signal an underlying thyroid problem.

16. Vitamin D 25-Hydroxyvitamin D (D2, D3)

Hypothyroidism can impair your body's ability to absorb certain vitamins, like Vitamin D.

Over time, low levels of Vitamin D can affect your heart and your bones, reducing your overall bone density.

Check your levels with this Vitamin D test to ensure your levels are where they should be. If they're too low (less than 12 ng/mL), you're Vitamin D deficient and could have hypothyroidism.

17. Vitamin B12 (Cobalamin)

Your B-vitamin levels are another way to determine how well your body is functioning.

In the case of people with hypothyroidism, a Vitamin B12 deficiency often results from gradual damage to the digestive tract. This prevents the absorption of vital nutrients like B-vitamins, which are essential to your wellbeing.

Vitamin B12 test will reveal if you're within the normal range (200-900 nanograms per milliliter (ng/mL).

18. Vitamin B6 (Pyridoxal Phosphate)

A final test you can take for hypothyroidism is Vitamin B6.

B6 is essential for your body's protein, fat, and carbohydrate metabolism. It also aids in the creation of red blood cells and neurotransmitters.

If you have an underactive thyroid, your body won't absorb B6 as efficiently as it should. This test will determine if your Vitamin B6 levels are normal (5-50 micrograms per liter).

Symptoms of Hypothyroidism? Order Your Tests Today

Hypothyroidism is a common condition with many treatment options available. But first, you have to get diagnosed.

Are you noticing hypothyroidism symptoms? Is there a history of hypothyroidism or other autoimmune diseases in your family? Or do you just feel like something is "off" and you can't quite figure out what it is?

If you answered "Yes" to any of these questions, it's time to take action. Before you can seek hypothyroidism treatment, you need to find out exactly what's happening inside your body.

Keep in mind that test results alone can't prove or diagnose any condition, including hypothyroidism. You'll need to review your results with your doctor before you can receive an official diagnosis and treatment plan.

Now that you know how to test for hypothyroidism, the only thing left to do is get started.

Click here to view our most popular thyroid health panels and take the first step towards a healthier you.