How Does Diabetes Occur?

Diabetes is a metabolic condition in which the body does not properly regulate the glucose, or sugar, in the blood. When you eat carbohydrates, your body breaks them down into sugars, including glucose. Glucose is transported by the bloodstream to the cells, where it is used for energy. The hormone insulin, secreted by the pancreas, is responsible for moving glucose from the blood into the cells. People with diabetes either do not make insulin, or their body does not properly respond to insulin, resulting in chronically elevated blood glucose.

Type 1 Diabetes

Type 1 diabetes develops as a result of an autoimmune attack on the pancreas that causes it to stop producing the hormone insulin. Without insulin, blood glucose is not regulated and type 1 diabetes develops. The exact cause is unknown, but the illness tends to run in families. Among people with a genetic predisposition for type 1 diabetes, an environmental trigger appears to stimulate the immune system attack on the pancreas. Certain viral infections in the first year of life are associated with an increased risk for type 1 diabetes.

Type 2 Diabetes

According to the Centers for Disease Control and Prevention, type 2 diabetes accounts for 90 to 95 percent of all diabetes cases 26. Type 2 diabetes typically begins with insulin resistance, a condition in which the pancreas produces insulin but the body cells do not respond to it properly. As the disease progresses, the pancreas may eventually lose its ability to produce insulin. Type 2 diabetes also involves a strong genetic component combined with other risk factors, including obesity and a sedentary lifestyle.

Gestational Diabetes

Gestational diabetes is a form of glucose intolerance that develops during pregnancy. According to the CDC, as many as 18 percent of pregnancies may be affected. Although the cause is unknown, it occurs more often in obese women and women with a family history of diabetes. Women who develop gestational diabetes are at increased for type 2 diabetes after their pregnancy.


The results of the Diabetes Prevention Program, a study conducted by the National Institute of Diabetes and Digestive and Kidney Diseases, showed that you can delay or even avoid type 2 diabetes through lifestyle changes, including increased physical activity and a diet low in fat and calories 79. Even a modest weight loss -- 5 to 7 percent of total body weight -- along with increased physical activity sharply reduced study participants' risk for developing type 2 diabetes. The American Diabetes Association recommends losing weight if you are overweight, increasing physical activity and eating a healthy diet focused on vegetables, fruits and lean meats 1458.