Insulin, Fasting LabCorp

The fasting insulin tests measures the amount of insulin, the hormone that transports glucose in to the cells of the body. Glucose, a sugar that comes from food, is the body's main source of energy. Our bodies break down foods that we eat into glucose and other nutrients, which are then absorbed into the bloodstream from the gastrointestinal tract. Following meals, glucose levels typically rise and trigger the pancreases to make insulin, thereafter releasing it in to the bloodstream. Insulin works like a key that opens the doors to cells and allows glucose to enter. Without insulin, glucose cannot get into the cells and remains in the bloodstream. For good health, the body must be able to keep insulin and glucose levels properly balanced. With too little insulin, blood sugar remains higher than normal (a condition known as hyperglycemia) and cells cannot get the energy they need. With too much insulin, blood sugar will decrease (hypoglycemia), causing symptoms such as sweating, trembling, lightheadedness, and possibly shock. The most common cause of abnormal fluctuations in blood sugar is diabetes.