Vitamin B12 Deficiency and Folate Deficiency

A diagnosis of vitamin B12 or folate deficiency anemia can often be made based on your symptoms and the results of vitamin b12 tests. If you have symptoms of Vitamin B12 and folate deficiency, it's essential to get tested. Learn about the different types of blood tests here.    

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Folate levels have diagnostic significance in nutritional deficiencies, especially in cases of severe alcoholism, function damage to the upper third of small bowel, pregnancy and various forms of megoblastic anemia. Since serum folate levels are subject to rapid changes reflecting diet and absorption, RBC folate may be a better diagnostic tool since the levels remain fairly constant.

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Folic acid deficiency is common in pregnant women, alcoholics, in patients whose diets do not include raw fruits and vegetables, and in people with structural damage to the small intestine. The most reliable and direct method of diagnosing folate deficiency is the determination of folate levels in both erythrocytes and serum. Low folic acid levels, however, can also be the result of a primary vitamin B12 deficiency that decreases the ability of cells to take up folic acid

Vitamin B12 is decreased in pernicious anemia, total or partial gastrectomy, malabsorption and certain congenital and biochemical disorders

Folic acid deficiency is common in pregnant women, alcoholics, patients with diets that do not include raw fruits and vegetables, and people with structural damage to the small intestine. The most reliable and direct method of diagnosing folate deficiency is the determination of folate levels in both erythrocytes and serum. Low folic acid levels, however, can also be the result of a primary Vitamin B12 deficiency that decreases the ability of cells to take up folic acid. Vitamin B12 is decreased in pernicious anemia, total

Vitamin B12 Binding Capacity, Unsaturated (Transcobalamin)

Clinical Significance

Vitamin B12 Binding Capacity, Unsaturated (Transcobalamin), binds and transports vitamin B12 in the circulation. Increased concentrations are associated with patients with myeloproliferative disorders. Decreased concentrations are seen in individuals with megaloblastic anemia or Transcobalamin deficiency.

Alternative Name(s) 

Transcobalamin, B12 Binding Capacity

NOTE: Only measurable biomarkers will be reported.

A Complete Blood Count (CBC) Panel is used as a screening test for various disease states including anemia, leukemia and inflammatory processes.

A CBC blood test includes the following biomarkers: WBC, RBC, Hemoglobin, Hematocrit, MCV, MCH, MCHC, RDW, Platelet count, Neutrophils, Lymphs, Monocytes, Eos, Basos, Neutrophils (Absolute), Lymphs (Absolute), Monocytes(Absolute), Eos (Absolute), Basos (Absolute), Immature Granulocytes, Immature Grans (Abs)

NOTE: Only measurable biomarkers will be reported.

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Elevated levels of homocysteine are observed in patients at risk for coronary heart disease and stroke.

Intrinsic Factor, produced by cells lining the stomach, binds vitamin B12 (cyanocobalamin) to facilitate absorption of the vitamin. Blocking antibody impedes the action of Intrinsic Factor as observed in approximately half of the patients who develop pernicious anemia.

Samples should not be collected from a patient who has received Vitamin B12 injection therapy within the last week.

The methylmalonic acid (MMA) test may be used to help diagnose an early or mild vitamin B12 deficiency. It may be ordered by itself or along with a homocysteine test as a follow-up to a vitamin B12 test result that is in the lower end of the normal range.

Methylmalonic acid is metabolized as methylmalonyl CoA from the catabolism of certain amino acids and fatty acids. Methylmalonyl CoA is then converted to Succinic acid by the following reaction: Methylmalonic Acid Methylmalonyl CoA Mutase + B12 Succinic Acid The enzyme Methylmalonyl CoA mutase requires Vitamin B12 (Cobalamin) as a cofacter. MMA is used to evaluate cobalamin deficiency. Elevated serum MMA reflects decreased tissue cobalamin levels and is an early indicator of vitamin B12 deficiency. Cobalamin dependent neurological disease with normal hematologic parameters and serum B12 levels is frequently associated with significant elevations of serum methylmalonic acid. Methylmalonic Acidemia is an autosomal recessive inborn error of metabolism, in which there is a deficiency of the enzyme methylmalonyl CoA mutase, resulting in a large accumulation of MMA in serum and urine. There is also a combined defect in the cobalamin pathway with elevation of both MMA and homocysteine.

Gastric Parietal Cell Antibodies (GPA) test results are used in the diagnosis of pernicious anemia.

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Use in evaluating erythropoietic activity.

Vitamin C is an antioxidant involved in connective tissue metabolism, drug-metabolizing systems, and mixed-function oxidase systems to list a few. Vitamin C deficiency causes scurvy; manifestations include impaired formation of mature connective tissue, bleeding into the skin, weakness, fatigue, and depression.

9 Blood Tests to Help Identify Vitamin B12 and Folate Deficiency

Are you feeling tired, sluggish, or irritable? Have you noticed changes in your digestion? You could be dealing with a vitamin deficiency. 

The majority of people in the United States consume adequate levels of B12 and folate. However, it's estimated that three percent of men and eight percent of women are deficient. 

A vitamin deficiency can come with a number of consequences. It's important to keep an eye on odd symptoms you're experiencing in case you could be a part of the three or eight percent.

If you're looking for a vitamin B12 deficiency test, you'll benefit from having some background information on the deficiency, its symptoms, treatments, etc. So keep reading to learn more. 

What Are Vitamin B12 and Folate?

Along with folate and vitamin C, vitamin B12, also called cobalamin, helps the body make new proteins. The proteins make red and white blood cells, repair cells, and synthesize DNA.

Vitamin B12 is not naturally produced in the body. Therefore, a person needs to get the right amount from their diet. Red meat, fish, poultry, milk, yogurt, and eggs contain cobalamin.

Folate is also a vitamin the body does not make naturally. It's especially important during pregnancy for cell division. It's commonly found in leafy green vegetables, peas and dry beans, liver, yeast, and citrus fruits. 

So, what causes vitamin B12 deficiency? When someone is dealing with a vitamin B12 deficiency, it's most often because they're not getting enough through their diet or supplements.

When it comes to dietary deficiencies, vegans are the most likely to suffer because of the lack of animal products. However, dietary deficiencies are not the only reason people may develop a B12 deficiency. 

Two other reasons someone may be suffering from vitamin B12 deficiency symptoms are inadequate absorption and increased need. If the vitamin B12 absorption process stops, that can cause the body to absorb less than what it needs. In regard to increased need, some diseases and conditions, like pregnancy or cancer, can boost the need for B12. 

Signs and Symptoms of Vitamin B12 and Folate Deficiency 

In some cases, a mild vitamin B12 and folate deficiency causes no symptoms. Minor changes in diet could fix the issue because a person even realizes something is off. As the deficiency worsens, however, the signs and symptoms become significantly more noticeable. 

Some of the most common signs and symptoms of a vitamin B12 deficiency include the following: 

  • Diarrhea
  • Constipation 
  • Dizziness 
  • Fatigue 
  • Muscle weakness 
  • Loss of appetite 
  • Pale skin 
  • Rapid heart rate
  • Irregular heartbeats 
  • Shortness of breath 
  • Sore or smooth tongue and month 
  • Tingling, numbness, and/or burning in the feet, hands, arms, and legs 
  • Paranoia 
  • Irritability 
  • Vision loss 
  • Weight loss 
  • Unsteady movements 
  • Mental confusion 

If you notice signs of a vitamin B12 deficiency, it's important to learn about the blood tests that can confirm or deny your suspected problem. While you may think you need to head to the doctor to get that done, you have online testing options from Ulta Lab Tests to make the process easier.

Consequences of an Untreated Vitamin B12 Deficiency

If a vitamin B12 deficiency goes untreated, there are several potential consequences. The most common is anemia. When your body doesn't make enough red blood cells, you won't have enough oxygen to your tissues and organs. Untreated anemia can result in heart failure. 

Anemia can also cause nerve problems. This is because B12 helps your body produce myelin. Myelin is essentially a protective layer throughout your nervous system. When those layers break down, nerve fibers can get damaged, which can cause numbness. Left untreated, paralysis is possible. 

A vitamin B12 deficiency can also cause mental health issues like depression, anxiety, insomnia, confusion, and visual or audio hallucinations. In extreme cases, patients can experience extrapyramidal symptoms where the body moves uncontrollably. 

Some doctors and scientists believe there is also a connection between B12 deficiencies and brain issues like dementia and Alzheimer's disease. The brain naturally shrinks with age, but depleted B12 can speed up the process by increasing the level of amino acids in the brain. 

Unfortunately, that's not where the consequences stop. Some rarer conditions related to B12 and folate deficiency include infertility, osteoporosis, COPD, and infertility. 

Blood Tests for Vitamin B12 and Folate Deficiency 

If it's suspected you have a vitamin B12 deficiency, there are a number of blood tests that can confirm or deny the suspicion. Folate is typically tested simultaneously, as the signs and symptoms of both deficiencies are similar. 

Does vitamin B12 deficiency show in blood tests? The short answer is yes. There are, however, a number of tests that can be used. Let's take a look at the nine types of blood tests used to diagnose vitamin B12 and folate deficiencies. 

1) Vitamin B12

vitamin B12 test is used to diagnose conditions like anemia and other autoimmune diseases. In addition, in the elderly, the test can help determine the cause of an altered mental state. If a person suffers from a B12 deficiency, their doctor will likely order the test over time to see if the established treatment is effective. 

2) Folate 

While folate is a separate blood test, it is often used together with B12. In addition to detecting illnesses, testing folate levels can provide a general overview of a person's health and nutritional status. 

3) CBC

A CBC, also known as a complete blood count, is used to screen for many conditions and diseases that affect blood cells. The test evaluates red blood cells, white blood cells, and platelets. 

Red blood cells contain hemoglobin, which is the protein that transports oxygen throughout the body. While most red blood cells last 120 days, medical conditions can change that. When a person has vitamin B12 and folate deficiencies, their red blood cells appear abnormal in size and shape.

White blood cells are a crucial part of the body's immune system. So if the body is fighting an infection or inflammation, the numbers will come back abnormal. 

Platelets are cell fragments that assist with clotting. People who have diseases that cause low platelets are at risk of excessive bleeding and bruising. 

4) B Vitamins 

B vitamins are required for metabolism and energy. They're also needed for cell, skin, bone, muscle, organ, and nervous system health. B vitamins are water-soluble, which means you have to eat foods rich in B vitamins to meet your body's needs. 

When you get tested for B vitamins, your doctor will review your levels for thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxal phosphate (B6), biotin (B7), folate (B9), and cobalamin (B12). 

In regard to test results, low levels could indicate a B vitamin deficiency, and high levels can be associated with vitamin toxicity. 

5) Methylmalonic Acid

Testing methylmalonic acid can detect early or mild vitamin B12 deficiency. The acid is needed for metabolism and energy production. As methylmalonic acid rises in your blood, vitamin B12 levels decrease. 

While the body has measures to level the two out, someone with malabsorption issues could experience numbness, swelling, and jaundice. 

6) Homocysteine

Homocysteine is an amino acid. It is present in all cells of the body and is quickly converted into other products. Vitamin B12 and folate, along with B6, are needed to metabolize homocysteine. 

If a blood test reveals homocysteine levels are elevated, the patient could have a B12 deficiency. Additional testing will be needed to get to the root of the problem. 

Higher levels of homocysteine can also indicate a higher risk for stroke, atherosclerosis, coronary heart disease, or peripheral vascular disease. 

7) Intrinsic Factor Antibody 

Intrinsic factor antibodies are proteins made by the immune system. The protein is produced by specialized cells in the lining of the stomach wall. 

During digestion, stomach accidents release vitamin B12 and bind to intrinsic factor antibodies. With an intrinsic factor, vitamin B 12 goes unabsorbed, and a person can develop anemia. 

8) Parietal Cell Antibody 

Parietal cell antibodies are proteins produced by the immune system. The antibodies mistakenly target cells that line the stomach wall. 

You could have this test completed if you or your doctor believes you have pernicious anemia. Pernicious anemia is an autoimmune disease that flares when the body's immune system targets its own tissues. 

9) Gastrin 

Gastrin, produced by the G-cells, is a hormone that's part of the stomach's antrum. This blood test is usually used to evaluate recurrent peptic ulcers and other types of severe abdominal pain or symptoms. 

While this test isn't directly used to diagnose a vitamin B12 deficiency, its results can help you decide your next step. 

gastrin test is commonly used when a patient suffers from diarrhea, abdominal pain, peptic ulcers, and fatigue. 

While most vitamin B12 and folate deficiencies can be identified with tests at the top of the list, you may need additional testing if your results are unclear. 

With the number of tests Ulta Lab Tests offers, you'll be on track to understanding your body's needs in no time. Test results come as quickly as one to two days, so you won't have to wait weeks to find out if you have a deficiency that needs to be addressed. 

Understanding the Results of a Vitamin B12 Deficiency Test 

If your test results confirm you have a vitamin B12 deficiency, you may need to undergo additional testing to reach a diagnosis. 

It's important to note that dietary deficiency of B12 or folate is uncommon in the United States. This is because many foods are fortified with vitamins. 

In some instances, you could have a deficiency because of certain medications. If your test results indicate that, you can talk with your doctor about finding a new treatment method or adding supplements to your diet. 

Treating a Vitamin B12 Deficiency 

In most instances, treating vitamin deficiencies involves changes in diet and adding supplements. 

For a folate deficiency, folic acid supplements are often suggested. However, once the body's folate level is where it needs to be, which can be confirmed with follow-up blood tests, you'll likely be able to stop taking the supplements. 

With a B-12 deficiency, patients usually start with oral supplements, but that's not always enough. If blood tests do not show any improvements with traditional supplements, B12 injections are an option. 

But how long does it take to recover from B12 deficiency? That answer depends on how well you follow your treatment plan and how your body responds. 

If blood tests confirm you have a vitamin B12 and folate deficiency, you'll want to consider asking your doctor questions about your condition and treatment options. Some of the most common questions, and their answers, patients ask include the following: 

Is vitamin B12 deficiency dangerous?

If left untreated, a B12 deficiency can cause serious complications. 

Does vitamin B12 deficiency cause memory loss?

Yes, vitamin B12 deficiency can cause memory loss. 

Can vitamin B12 deficiency cause muscle pain?

Yes, vitamin B12 deficiency can cause muscle pain. 

Can vitamin B12 deficiency cause lightheadedness?

Yes, vitamin B12 deficiency can cause lightheadedness, particularly when a person stands up too quickly. 

Can vitamin B12 deficiency cause insomnia?

Insomnia and fatigue are the most common and debilitating symptoms related to vitamin B12 deficiency. 

Can vitamin B12 deficiency cause fever?

A severe vitamin B12 deficiency can cause a fever. 

Can vitamin B12 deficiency cause dizziness?

Frequent dizziness and vertigo can indicate a vitamin B12 deficiency. 

Cause vitamin B12 deficiency cause diabetes?

No, but diabetes can increase your risk of having a B12 deficiency. 

Can rheumatoid arthritis cause vitamin B12 deficiency? 

Not necessarily, but a portion of patients with RA do have vitamin B12 deficiency. 

Once you have a handle on your vitamin deficiency, you'll be able to get back to living a high-quality life. 

Order Lab Tests Online

For many patients, driving to a hospital or medical facility for bloodwork can be time-consuming and costly. Fortunately, Ulta Lab Tests offers vitamin B12 deficiency test options. 

When you order lab work from Ulta Lab Tests, your results are kept secure and confidential. And you won't have to worry about getting a referral from your doctor, either. We also offer the lowest prices on lab tests, so health insurance isn't a problem if you're not covered. 

If you're ready to take control of your health, contact us today. 

The body needs two B complex vitamins – folate and B12 – for several crucial functions. For instance, the body uses these vitamins to make white blood cells, red blood cells, synthesize DNA, and repair cells and tissues. B12 is also critical for nerve cell function. 

Unfortunately, the body cannot produce folate (also known as vitamin B9 and folic acid), and B12 and the vitamins are only supplied by one’s diet. A healthy body should contain ample vitamin B12 stores to last 3 to 5 years. However, the body does not store a lot of folate vitamins. When one is diagnosed with folate and/or B12 deficiency, it denotes a chronic shortage of one, or in some worse case scenarios, both vitamins. 

In the United States, folate and B12 deficiencies are not common conditions that healthy adults face as the body can store the vitamins for some time. Typically, adults eat diets that contain the vitamins or are supplemented with these vitamins, thereby meeting their daily requirements.

However, some individuals are at risk of experiencing deficiency, including: 

  • The elderly 
  • Individuals with intestinal conditions and issues that prevent their digestive systems from absorbing enough of these two vitamins 
  • Pregnant women, as they need an increased amount of both vitamins 
  • Vegans and vegetarians 
  • Heavy alcohol drinkers 
  • Individuals living with long-term use of certain medicines  

B12 deficiency among the demographic of 60 and below is estimated to be approximately 6% in the United Kingdom and the United States. The B12 deficiency is estimated to be prevalent in more than 20% among individuals age 60 years and more. 

Folate and B12 deficiencies and their signs and symptoms can take anywhere from months to years before they manifest in adults. Children and infants tend to show signs of deficiency more rapidly as their tender years are not enough to allow them to accumulate enough stores. 

Over time, the deficiency in folate and/or B12 can give rise to the condition of enlarged red blood cells known as macrocytic anemia. The production of fewer and enlarged blood cells reduces the blood cells’ ability to transport oxygen from the lungs to the body. People suffering from anemia will experience short-breath, light-headedness, and weaknesses.  

Megaloblastic anemia, which is a type of macrocytic anemia that is associated with cellular changes to one’s bone marrow, aside from the production of enlarged and fewer red blood cells. This type of anemia is also characterized by a decrease in the production of white blood cells, platelets, and reticulocytes. 

A B12 deficiency can also cause varying degrees of nerve damage or neuropathy, which results in numbness and tingling sensation in a person’s feet and or hands. In some severe cases, mental changes are observed, resulting in irritability, confusion, or even dementia. 

Pregnancy demands an increased amount of folate for the proper development of fetus owing to the increased demands induced by rapidly developing fetal cells. Pregnancy-related folate deficiency, especially during the early weeks when many expectant mothers are oblivious of their pregnancies, can lead to premature births. In other cases, the deficiency can give rise to neural tube birth defects (NTDs), including spina bifida. 

The Food and Drug Administration mandates an increased supplementation of all numerous grain products as a measure to curb and prevent NTDs. This measure resulted in a 50% decrease in NTDs in the United States. Even with these efforts, getting the right amount of folate can be a daunting task. As such, pregnant women are recommended to take 400 micrograms of supplementing folate every day. 

Signs and Symptoms Deficiencies 

The onset of folate and B12 deficiencies gives rise to subtle and nonspecific signs and symptoms. Some of the signs are, in fact, the effects of nerve damage, megaloblastic anemia, and/or gastrointestinal changes.

The affected individuals might experience mild to severe signs and symptoms, which might include: 

  • Dizziness
  • Diarrhea
  • Loss of appetite 
  • Constipation
  • Muscle weakness 
  • Fatigue
  • Sore or smooth mouth and tongue
  • Pale skin
  • Irregular heartbeats
  • Shortness of breath 
  • Rapid heart rate
  • Confusion and/or forgetfulness 
  • Numbness, tingling, and/or burning in the arms, hands, feet, and legs (with B12 deficiency) 
  • Irritability
  • Paranoia


Folate and/or B12 deficiency has a variety of causes. Some of them are: 

  • Insufficient Dietary Intake 

B12 is mainly sourced from animal-based foods such as poultry, eggs, fish, meat, and milk. Foliate, also known as vitamin B9 or folic acid, is mainly sourced from leafy green veggies, dry beans, citrus fruits, vitamin-fortified cereals, and yeast. 

With the body being capable of storing vitamin B12 worth several years in the liver, and the fact that a variety of foods consumed in the U.S. are fortified with the vitamin, a dietary deficiency of the vitamin if relatively rare. However, it can occur among people with poor nutrition, malnourishment, vegans, and even breastfed infants of vegan mothers.  

In adults, a dietary deficiency does not yield to symptoms until the vitamin stores in the body are depleted. Deficiencies in infants and children can occur quickly since they have had little to no time to accumulate enough vitamin stores, as is the case in adults. 

Folate deficiencies were common in the past. However, since 1997 when the United States government mandated the fortification of bread, cereals, and other grain products with folic acid, folate deficiency cases dropped. Folate, a water-soluble vitamin, cannot be stored in the fat tissues. On average, the total amount of folate available in the body is 15 to 30 mg. Around half of it is stored in the liver, with the rest being stored in the blood as well as other tissues. Since folic acid is stored in small quantities, you should consume it much more regularly than B12. 

  • Malabsorption  

Both folate and B12 deficiencies can occur in people with conditions that negate the absorption of the vitamin in the small intestines. The intake of vitamin B12 occurs in a series of steps. First and foremost, the vitamin is broken down from protein by pepsin and stomach acid.  

In the next step, the vitamin is processed in the small intestine, where the vitamin binds with intrinsic factor (IF) to form the B12-IF complex. IF is a protein made by the parietal cells in the stomach. The B12-IF complex is absorbed in the small intestines, after which the transcobalamin’s “carrier proteins” bind the complex. The final step is entering into circulation. 

People who suffer from a disease that affects any of these steps will experience deficiencies as the absorption of B12 is impaired. 

Some of the conditions that can affect these steps are: 

  • Pernicious anemia – An Autoimmune disease that affects B12 absorption. The condition is the most common cause of B12 deficiency, and it affects the production of intrinsic factor. The IF is produced by the parietal cells that line the stomach. When one suffers from pernicious anemia, the inflammation can damage the cell, thereby affecting the production of IF. Consequently, this prevents the intestines from absorbing B12. With insufficient B12 absorption and low availability of the vitamin, the body produces fewer and enlarged red blood cells, which is termed as megaloblastic anemia, a type of macrocytic anemia. 
  • Celiac Disease – This is another autoimmune disease whereby the immune system produces an inappropriate response to the gluten, which is a protein found in rye, wheat, and barley. 
  • Inflammatory Bowel Disease – It includes ulcerative colitis and Crohn’s disease. 
  • Presence of parasites or bacterial overgrowth in the intestines 
  • A Reduction in Stomach Acid Production – Stomach acid is used to separate B12 from the source proteins. The reduction of stomach acid production is the most common cause of B12 deficiency among individuals using drugs such as proton pump inhibitors and H2 receptors antagonists as they suppress acid production. It is also a common cause among the old. 
  • Stomach Surgery – Any stomach surgery that removes part of the stomach and affects the parietal cells and or the intestines can reduce the absorption of B12. As such, undergoing a gastric by-pass can cause a B12 deficiency. 
  • Chronic Pancreatitis – Long-lasting pancreases inflammation, typically caused by long-term alcohol abuse of gallstones, can result in B12 deficiency.  

Increased Need for B12 and/or Folate 

Pregnancy increases DNA synthesis and cell production, which, in turn, increases the need for folate. It is recommended that women take prenatal vitamin supplements that include folic acid before getting pregnant and throughout the pregnancy to prevent some of the birth defects. Moreover, women planning to get pregnant should observe a proper die. Furthermore, they should consider taking supplements that ensure they meet the daily minimum recommended consumption of 400 mcg of folate.  

Keep in mind that neural tube defects can arise during the first weeks of pregnancy even before you realize you are pregnant. You can read more on this topic by reading the Neural Tube Defects article. Additionally, folate deficiency only intensifies with pregnancy. This can lead to neural tube defects and premature birth, as well. 

Individuals with chronic hemolytic anemia (including sickle cell anemia) or with cancer that has metastasized (spread) need more folate. 

Some anti-seizure medications, including phenytoin, can reduce folate by blocking its absorption. 

The anti-cancer drug Methotrexate affects the body’s use of folate and metabolism. 

Other Causes: 

Alcoholism or heavy alcohol drinking can cause folate and or B12 deficiencies owing to malabsorption, poor nutrition, and a decrease in the amount of B12 released from dietary proteins. 

Some prescription drugs can cause B12 deficiency. Metformin, a diabetes drug, blocks the absorption of B12. Omeprazole, which is an acid reflux drug, reduces the production of gastric acid, which prevents the release of B12 from the proteins one eats. 

A methylenetetrahydrofolate reductase gene (MTHFR) mutation impairs the function of folate. Approximately, 1% African Americans, 10% Caucasians, and 25% Hispanics, may have this mutation. 


B12 deficiency screening is not recommended unless a patient has high-risk factors. Lab testing can be used to detect vitamin deficiency and determine the level of severity and the underlying cause of symptoms. The test can also help monitor the effectiveness of the treatment.  

The Variety of Test That Can Diagnose and Or Monitor Folate and B12 Deficiencies: 

CBC – The complete blood count test is a group of tests that evaluate the health of one’s blood cells. 

CBC test determines the number of red blood cells, white blood cells, hematocrit, hemoglobin level, mean corpuscular volume (MCV, which is indicative of the RBC size), and platelet count. Megaloblastic anemia/Macrocytic anemia and enlarged RBC are associated with folate and B12 deficiency, which routine CBC can help identify. 

These tests can also help identify abnormal physical characteristics of the cells, thereby indicating of B12 and folate deficiencies. For instance, the deficiencies decrease platelets, RBCs, hemoglobin, hematocrit, and WBCs.  

B12 Blood Level – A low B12 blood level indicates a deficiency, although it does not determine the cause of the deficiency. Reasons for the deficiency can be IF production inhibition causing malabsorption. This test is also ordered to monitor treatment effectiveness.  

Folate Level – RBC folate level or serum is tested to determine the folate level. A low level is indicative of deficiency. This test is also ordered to monitor the effectiveness of treatment. You should note that come health officials and organizations do not recommend testing folate levels. Instead, they recommend treating the patient suffering from a deficiency with necessary supplements. 

Methylmalonic acid (MMA) – Generally, low B12 is associated with high MMA. An MMA test can help detect early or mild B12 deficiency.  

Homocysteine Test – Homocysteine tends to be elevated in instances of folate and B12 deficiency. 

Tests Used to Help Determine B12 Deficiency Causes 

Intrinsic Factor Antibody Test – The Intrinsic Factor antibody impedes the IF from functioning. It prevents the IF from carrying B12 or the B12 from being absorbed in the small intestines. 

Parietal Cell Antibody Test – This is an antibody that affects the parietal cells that make the IF. The antibody, which is present in a lot of people with pernicious anemia and other autoimmune diseases, can impede the production of intrinsic factor. 

Gastrin Test – This is a hormone that regulates the production of gastric acid during the digestive process. An increased level of gastrin is sometimes seen in people with pernicious anemia.