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Diabetes: Definition, Causes and Symptoms

What is diabetes?

Diabetes is a disease that affects your body’s ability to produce or use insulin. Insulin is a hormone. When your body turns the food you eat into energy (also called sugar or glucose), insulin is released to help transport this energy to the cells. Insulin acts as a “key.” Its chemical message tells the cell to open and receive glucose. If you produce little or no insulin, or are insulin resistant, too much sugar remains in your blood. Blood glucose levels are higher than normal for individuals with diabetes. There are two main types of diabetes: Type 1 and Type 2.

What is Type 1 diabetes?

When you are affected with Type 1 diabetes, your pancreas does not produce insulin. Type 1 diabetes, once called juvenile diabetes, is often diagnosed in children or teens. However, it can also occur in adults. This type accounts for 5-10 percent of people with diabetes.

What is Type 2 diabetes?

Type 2 diabetes occurs when the body does not produce enough insulin, or when the cells are unable to use insulin properly, which is called insulin resistance. Type 2 diabetes is commonly called “adult-onset diabetes” since it is diagnosed later in life, generally after the age of 45. It accounts for 90-95 percent of people with diabetes. In recent years, Type 2 diabetes has been diagnosed in younger people, including children, more frequently than in the past.

Are there other forms of diabetes?

Gestational diabetes occurs during pregnancy and affects about 18 percent of all pregnancies, according to the American Diabetes Association

Gestational diabetes usually goes away after pregnancy, but once you've had gestational diabetes, your chances are higher that it will happen in future pregnancies. In some women pregnancy uncovers Type 1 or Type 2 diabetes and these women will need to continue diabetes treatment after pregnancy. 

There seems to be a link between the tendency to have gestational diabetes and Type 2 diabetes, and many women who had gestational diabetes develop Type 2 diabetes later on. Gestational diabetes and Type 2 diabetes both involve insulin resistance. Certain basic lifestyle changes may help prevent diabetes after gestational diabetes.

Another form is prediabetes. This condition causes a person’s blood sugar levels to be higher than normal but not high enough to be diagnosed with diabetes. The American Diabetes Association estimates that there are 84.1 million Americans that have pre-diabetes in addition to the 30.3 million with diabetes.

What causes diabetes?

Genetics, lifestyle and environment can be causes of diabetes. Eating an unhealthy diet, being overweight or obese and not exercising enough may play a role in developing diabetes, particularly Type 2 diabetes. Type 1 diabetes is caused by an autoimmune response. The body’s immune system attacks and destroys the insulin producing beta cells in the pancreas.

How does diabetes affect my body?

Over time, high blood sugar levels (also called hyperglycemia) can lead to kidney disease, heart disease and blindness. The excess sugar in the bloodstream can damage the tiny blood vessels in your eyes and kidneys, and can harden or narrow your arteries.

What are the symptoms of diabetes?

  • Extreme thirst
  • Frequent urination
  • Blurry vision
  • Extreme hunger
  • Increased tiredness
  • Unusual weight loss

How can I find out if I have diabetes? 

Sometimes a routine exam by an eye doctor or foot doctor will reveal diabetes. Diabetes affects the circulation to your feet and the tiny blood vessels in your eyes. If your eye doctor or your foot doctor suspects you have diabetes, they will recommend you see your regular physician for a blood sugar level test.

The most common test is a fasting blood glucose test. After not eating for at least eight hours, usually overnight, your doctor will take a blood sample. The normal, non-diabetic range for fasting blood glucose is 70 to 110 mg/dl. If your level is 126 mg/dl or greater, you may have diabetes.

If I have signs of diabetes, what should I do?

See your doctor so he or she can perform tests to determine whether or not you have diabetes or prediabetes. Your doctor will make recommendations to bring down your blood sugar level to treat diabetes or so that you can delay the development of Type 2 diabetes.

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