Home > Encyclopedia of Science > Diabetes Mellitus

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Diabetes mellitus is a disease caused by the body's inability to use the hormone insulin. Insulin is normally produced in the pancreas, a gland attached to the small intestine. Its function is to convert carbohydrates into glucose. Glucose (also known as blood sugar) is the compound used by cells to obtain the energy they need to survive, reproduce, and carry out all their normal functions.

When cells are unable to use glucose for these functions, they use fat instead. One product of the metabolism of fats is a group of compounds known as ketones. Ketones tend to collect in the blood and disrupt brain functions.

Common signs of diabetes are excessive thirst, urination, and fatigue. The long-term effects of diabetes include loss of vision, decreased...