Diabetes treatment: Using insulin to manage blood sugar

Understanding how insulin affects your blood sugar can help you better manage your condition. By Mayo Clinic Staff

Insulin therapy is often an important part of diabetes treatment. Understand the key role insulin plays in managing your blood sugar, and the goals of insulin therapy. What you learn can help you prevent diabetes complications.

The role of insulin in the body

It may be easier to understand the importance of insulin therapy if you understand how insulin normally works in the body and what happens when you have diabetes.

  • Regulate sugar in your bloodstream. The main job of insulin is to keep the level of sugar in the bloodstream within a normal range. After you eat, carbohydrates break down into sugar and enter the bloodstream in the form of glucose, a sugar that serves as a primary source of energy. Normally, the pancreas responds by producing insulin, which allows sugar to enter the tissues.
  • Storage of excess glucose for energy. After you eat — when insulin levels are high — excess glucose is stored in the liver in the form of glycogen. Between meals — when insulin levels are low — the liver releases glycogen into the bloodstream in the form of sugar. This keeps blood sugar levels within a narrow range.

If your pancreas secretes little or no insulin (type 1 diabetes), or your body doesn't produce enough insulin or has become resistant to insulin's action (type 2 diabetes), the level of sugar in your bloodstream increases because it's unable to enter cells. Left untreated, high blood sugar can lead to complications such as blindness, nerve damage (neuropathy) and kidney damage.

Aug. 07, 2013 See more In-depth