Type 1 diabetes
Type 1 diabetes occurs because the insulin-producing cells (called beta cells) of the pancreas are damaged. People with type 1 diabetes produce little or no insulin, so glucose cannot get into the body's cells for use as energy. This causes blood glucose to rise. People with type 1 diabetes MUST use insulin injections to control their blood glucose.

The damage to insulin-producing cells in type 1 diabetes occurs over a period of years. However, the symptoms of type 1 diabetes may occur over a period of days to weeks. Type 1 is the most common form of diabetes in people under age 20, but it can occur at any age.

Type 2 diabetes
Unlike people with type 1 diabetes, people with type 2 diabetes produce insulin. However, the insulin produced is either not enough or doesn't work properly in the body. When there is not enough insulin or the insulin is not used as it should be, glucose cannot get into the body's cells for use as energy. This causes blood glucose to rise.

Type 2 diabetes is most common in people who are over age 40 and who are overweight. Some people with type 2 diabetes can manage it by controlling their weight, watching their diet, and exercising regularly. Others may also need to take an oral glucose-lowering medication or insulin injections.

Gestational diabetes
Gestational diabetes is a high blood glucose level that occurs during pregnancy. As pregnancy progresses, the developing baby has an increased need for glucose. Hormone changes during pregnancy also affect the action of insulin, resulting in high blood glucose levels.

Pregnant women who have an increased risk of developing gestational diabetes include those who:

  • are over 25 years old
  • are above their normal body weight
  • have a family history of diabetes, and
  • are Hispanic, African-American, Native American, or Asian.

Usually, blood glucose levels return to normal after childbirth. However, women who have had gestational diabetes have an increased risk of developing type 2 diabetes later in life.

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