What's the difference between type 1 and type 2?

Type 1 is an autoimmune disorder in which the body mistakenly attacks its own pancreas. The pancreas then can no longer make insulin, a hormone (natural messenger chemical) needed to process glucose (blood sugar) for energy. Type 2 is a metabolic disorder in which the body stops using insulin properly and blood sugar builds up.

What's the big deal about high blood sugar?

High blood sugar (hyperglycemia) can damage the blood vessels and nerves. Long-term hyperglycemia can cause or worsen a wide range of health problems, including heart disease, stroke, eye diseases, kidney damage, skin disorders, foot problems and gum disease. A short-term bout of severe hyperglycemia can lead to a potentially fatal coma.

So it's good to have low blood sugar?

No. Low blood sugar (hypoglycemia) can also lead to coma and death. Doctors recommend that people keep their blood sugar within a normal range, not too high or low.

And what is my ideal blood sugar?

That depends partly on which blood test is used and when (e.g., before or after a meal). For example, with the fasting blood glucose test, used in diagnosing diabetes, normal blood sugar is below 100 milligrams per deciliter (mg/dL). With the oral glucose tolerance test, normal blood sugar is below 140 mg/dL two hours after the test begins. For people with diabetes, target levels depend on the individual and the doctor. Many diabetes patients need to check their own blood sugar several times a day with a small gadget called a glucose meter.

A blood test called the glycohemoglobin (A1C) test is used to monitor blood sugar control over the past few months. A goal for many diabetic patients is a maximum glycohemoglobin test result of 7 percent. That means that 7 percent of the hemoglobin (oxygen-carrying part of the blood) has glycated (combined) with the glucose in the blood.

A glycohemoglobin result of 6 percent translates to an average plasma blood glucose level of 135 milligrams per deciliter (mg/dL) over the past few months, a glycohemoglobin result of 7 percent translates to 170 mg/dL, a glycohemoglobin of 8 percent translates to 205 mg/dL, and so forth.

Do most diabetic people die of diabetes?

No. Heart disease is the biggest killer of people with diabetes. That's why it's so important to control blood pressure and cholesterol as well as blood sugar.

Can diabetes affect my sex life?

Yes. Uncontrolled blood sugar can cause yeast infections in women, erection problems in men and other sexual difficulties. But the risk of these conditions is reduced when blood sugar is controlled.

Is there a cure for diabetes?

Gestational diabetes (which develops in some pregnant women) and some cases of secondary diabetes (such as some caused by taking certain medications) are temporary, but otherwise doctors generally consider diabetes to be a chronic condition that can be managed rather than cured.

However, some doctors have reported resolution of type 2 diabetes in severely obese patients who underwent weight-loss stomach surgery. And some patients with type 1 diabetes who have undergone a pancreas transplant or experimental transplant of insulin-producing pancreatic cells have been able to stop taking insulin. But a pancreas transplant can eventually fail, and some cell transplant patients still need to take insulin.

Scientists are studying many potential cures for diabetes involving gene therapy, stem cells and other biotechnology.