Insulin is a hormone that is produced and stored in the beta cells of the pancreas. It is vital for the transportation and storage of glucose at the cellular level, helps regulate blood glucose levels, and has a role in lipid metabolism. When blood glucose levels rise after a meal, insulin is released to allow glucose to move into tissue cells, especially muscle and adipose (fat) cells, where is it is used for energy production. Insulin then prompts the liver to either store the remaining excess blood glucose as glycogen for short-term energy storage and/or to use it to produce fatty acids. The fatty acids are eventually used by adipose tissue to synthesize triglycerides to form the basis of a longer term, more concentrated form of energy storage. Without insulin, glucose cannot reach most of the body's cells. Without glucose, the cells starve and blood glucose levels rise to unhealthy levels. This can cause disturbances in normal metabolic processes that result in various disorders, including kidney disease, cardiovascular disease, and vision and neurological problems. Thus, diabetes, a disorder associated with decreased insulin effects, is eventually a life-threatening condition.