Diabetes is a chronic disease, which occurs when the pancreas does not produce enough insulin, or when the body cannot effectively use the insulin it produces. This leads to an increased concentration of glucose in the blood (hyperglycemia).
There are three main types of diabetes. Type 1 diabetes (previously known as insulin-dependent or childhood-onset diabetes) is characterized by a lack of insulin production. Type 1 diabetes is an autoimmune disease. An autoimmune disease results when the body’s system for fighting infection—the immune system—turns against a part of the body. In diabetes, the immune system attacks and destroys the insulin-producing beta cells in the pancreas. The pancreas then produces little or no insulin. A person who has type 1 diabetes must take insulin daily to live.
Type 2 diabetes is the most common form of diabetes. About 90 to 95 percent of people with diabetes have type 2. This form of diabetes is most often associated with older age, obesity, family history of diabetes, previous history of gestational diabetes, physical inactivity, and certain ethnicities. About 80 percent of people with type 2 diabetes are overweight. Type 2 diabetes is increasingly being diagnosed in children and adolescents. The symptoms of type 2 diabetes develop gradually. Their onset is not as sudden as in type 1 diabetes. Symptoms may include fatigue, frequent urination, increased thirst and hunger, weight loss, blurred vision, and slow healing of wounds or sores. Some people have no symptoms.
And the third type of diabetes is gestational diabetes, which is hyperglycemia that is first recognized during pregnancy. Some women develop gestational diabetes late in pregnancy. Although this form of diabetes usually disappears after the birth of the baby, women who have had gestational diabetes have a 40 to 60 percent chance of developing type 2 diabetes within 5 to 10 years. Maintaining a reasonable body weight and being physically active may help prevent development of type 2 diabetes. About 3 to 8 percent of pregnant women in the United States develop gestational diabetes. As with type 2 diabetes, gestational diabetes occurs more often in some ethnic groups and among women with a family history of diabetes. Gestational diabetes is caused by the hormones of pregnancy or a shortage of insulin. Women with gestational diabetes may not experience any symptoms.
What is Prediabetes? People with pre-diabetes have blood glucose levels that are higher than normal but not high enough for a diagnosis of diabetes. This condition raises the risk of developing type 2 diabetes, heart disease, and stroke.
Pre-diabetes is becoming more common in the United States. The U.S. Department of Health and Human Services estimates that at least 57 million U.S. adults ages 20 or older had pre-diabetes in 2007. Those with pre-diabetes are likely to develop type 2 diabetes within 10 years, unless they take steps to prevent or delay diabetes.
The good news is that people with pre-diabetes can do a lot to prevent or delay diabetes. Studies have clearly shown that people can lower their risk of developing diabetes by losing 5 to 7 percent of their body weight through diet and increased physical activity. A major study of more than 3,000 people with IGT found that diet and exercise resulting in a 5 to 7 percent weight loss—about 10 to 14 pounds in a person who weighs 200 pounds— lowered the incidence of type 2 diabetes by nearly 60 percent. Study participants lost weight by cutting fat and calories in their diet and by exercising—most chose walking—at least 30 minutes a day, 5 days a week.
Recent data from the Centers for Disease Control and Prevention (CDC) paint an urgent picture of the state of diabetes, estimating that nearly 26 million children and adults in the United States are now living with diabetes. With one out of every three Americans at high risk for type 2 diabetes, emphasis must be placed on prevention and lifestyle modifications that can delay or prevent type 2 diabetes, a debilitating disease that can lead to blindness, kidney failure, heart disease and death.
“We’ve seen that diabetes has been on the rise for quite a while, but the new data from the CDC is a real wake-up call. One in four Americans living with diabetes is still undiagnosed, highlighting how essential it is for Americans to know if they are at risk and take action, if needed,” said Robert R. Henry, MD, President, Medicine & Science, American Diabetes Association. “Let’s use these devastating new numbers as inspiration to work harder and stop diabetes in its tracks.”
Early diagnosis of type 2 diabetes is critical to successful treatment and delaying and preventing some of its complications. For many, diagnosis may come seven to ten years after the actual onset of diabetes, often only after patients have already started to show signs of one or more of its complications. Studies have shown that exercising 150 minutes a week and losing 7% of your body weight (about 15 pounds if you weigh 200 pounds), can prevent or delay type 2 diabetes by 57%.
2004-2006 National Health Interview Survey (NHIS), National Center for Health Statistics, Centers for Disease Control and Prevention. Available at: www.cdc.gov/nchs/nhis.htm.
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National Diabetes Fact Sheet of the National Center for Chronic Disease Prevention and Heath Promotion; NCHS; CDC; ADA; AACE
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