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Type 2 Diabetes

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Type 2 Diabetes
Approximately 95 percent of people with diabetes have type 2 disease (also called non-insulin-dependent diabetes mellitus or NIDDM). Those with type 2 produce insulin, but the cells in their bodies are "insulin resistant" -- they don't respond properly to the hormone, so glucose accumulates in their blood. Some people with type 2 diabetes must inject insulin, but most can control the disease through a combination of weight loss, exercise, a prescription oral diabetes medication, and tight control.

Risk Factors

• Like type 1 diabetes, type 2 disease also runs in families.
• Most people diagnosed with type 2 are age 30 or older. Half of all new cases are age 55 and older.
• Compared with whites and Asians, type 2 diabetes is more common among Native Americans, African-Americans, Latinos, and Hispanics.
• Insulin resistance worsens as weight increases and physical activity decreases. Many people with type 2 diabetes have sedentary lifestyles and are obese; they weigh at least 20 percent more than the recommended weight for their height and build.
• Lack of exercise, especially in those who are overweight, increases risk.
• If you developed gestational diabetes during pregnancy, you're at a higher risk of type 2 diabetes later.
• Women who have given birth to babies weighing 9 pounds or more are at an increased risk.
• These include thiazide diuretics (used to manage high blood pressure) and steroids (used to help with inflammatory conditions).

What Cause it?
Scientists are not certain, but type 2, like type 1 diabetes, runs in families, which suggests some genetic connection. In fact, a genetic link seems even stronger in type 2 diabetes than in type 1. Scientists have not yet put their finger on a single gene that causes the disease, but they are finding errors in several that may contribute to the disease. Researchers also suspect a genetic susceptibility to obesity.

Obesity is the single most important cause of type 2 diabetes. Definitions of obesity differ, but in general, you're obese if you weigh at least 20 percent more than what's recommended for your height and build. Three-quarters of people with type 2 diabetes are overweight. For reasons that remain unclear, carrying excess body fat somehow causes insulin resistance. That's why type 2 diabetes is usually treated with diet and exercise.

Losing weight and gaining muscle helps the body use insulin more efficiently. Where you carry your weight is as important as how much you carry. People who carry their fat above their hips have a greater risk of developing type 2 diabetes than those who carry it on their hips

Age also plays a role in type 2 diabetes. Half of all new diagnoses are in people age 55 and above, and nearly 11 percent of Americans ages 65 to 74 have type 2 diabetes. However, researchers don't know if age is a cause of type 2 diabetes or simply a reflection of the fact that people tend to gain weight and become less physically active as they grow older.