Diabetes is a disorder of metabolism—the way the body uses digested food for energy. To understand diabetes, it is helpful to understand how your body uses the foods you eat for energy.
What happens when you have diabetes?
When you eat, most of the food is broken down into glucose, a form of sugar. The glucose is pumped into your bloodstream where it will be made available to your cells. Your cells need the glucose for growth and energy.
Insulin is the hormone that moves the glucose from your blood into your cells. Your pancreas, a gland located just behind the stomach, secretes insulin into your bloodstream. As the insulin circulates, it acts like a key and unlocks the microscopic doors that allow the glucose to enter your cells. As the glucose in your blood deceases, the pancreas responds by lowering secretions of insulin.
Your liver acts as a glucose storage and manufacturing center. When you haven't eaten in a while, your liver releases stored glucose to keep your glucose level within a normal range.
When your body is healthy, your pancreas automatically produces the right amount of insulin necessary to move the glucose from your blood into your cells. When you have diabetes this process is disrupted. The pancreas may produce too little or no insulin. This prevents the glucose from leaving your bloodstream and moving into the cells. Or, the cells do not respond appropriately to the insulin.
The result is that glucose or sugar builds up in your blood. It overflows into the urine and passes out of the body in the urine. But the glucose takes all that energy with it, leaving the body without its main source of fuel.
Over the years, high blood glucose damages nerves and blood vessels, leading to complications such as heart disease, stroke, blindness, kidney disease, nerve problems, gum infections, and amputation. Uncontrolled diabetes can complicate pregnancy, and birth defects are more common in babies born to women with diabetes.