Editor's note: Ann Curley is the assignment manager for the CNN Medical News unit. She has been a type I diabetic for 40 years. Here she explains the basics to understanding diabetes.
Ann Curley pricks her finger with a rapid-firing needle to test her blood sugar level.
(CNN) -- Diabetes is a disease in which the body either doesn't produce insulin, or it doesn't properly use insulin, or both. Insulin is a hormone produced by the pancreas that metabolizes glucose, which is the source of energy for cells in the body.
There are two types of diabetes -- type I and type II.
Type I affects about 10 percent of all diabetes. I am a type I. My body doesn't produce insulin, so I need to take extra insulin for it to metabolize any carbohydrates that I eat.
Insulin cannot be taken orally, so it must taken by injection or by insulin pump, which is a tiny device that connects to the body with plastic tubing and feeds a constant drip of insulin. I use an insulin pump.
With type II diabetes, which is much more common, the body generally produces some insulin, but it isn't able to process it properly. Type II is often associated with obesity, and part of the difficulty for type II diabetics is that the extra insulin, which is circulating unused in the body, also causes the body to hold on to fat cells. A fine balance must be found between managing insulin sensitivity and losing weight.
Most type II diabetics are able to take oral drugs that allow their body to properly use the insulin they produce. Obesity is a known risk factor for type II diabetes, and its incidence has increased as obesity rates have climbed.
The key to good diabetes control is blood sugar, or glucose, management. And the reality is that poor glucose control dramatically increases the risk for health complications related to heart and blood vessel disease: heart attacks, stroke, blindness and peripheral vascular disease, when blood flow to the limbs becomes impaired -- sometimes resulting in amputation.
All of these problems can develop when a trio of factors -- blood glucose, blood pressure and cholesterol levels -- are not kept within recommended ranges. That's why the concept of "control" is such an important aspect of being diabetic.
The goal is to mimic what the body would do if it were producing insulin. Normally the body would make smaller, steady amounts of insulin between meals and overnight. This is called the basal rate. And the body would produce larger amounts when you eat in order to burn off the carbohydrates. This is called a bolus.
Diabetics who inject insulin generally use two types: a slower-acting product that manages the basal rate, and a quicker-acting bolus insulin when they eat food. The bolus and basal rates work to keep blood sugars constantly in control.
Insulin pumps do much the same thing. These are small devices connected to the body by a small tube. The pump can be used to drip insulin into the body to maintain the basal rate, then give extra boluses with meals. E-mail to a friend