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 is also called juvenile diabetes, since it is often diagnosed in children or teens. 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. 90-95 percent of people with diabetes have this type. 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.

Pre-diabetes is a condition that 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 41 million Americans that have pre-diabetes in addition to the 18.2 million with diabetes.

What causes diabetes?

The cause of diabetes is unknown. Genetics, diet, obesity and lack of exercise may play a role in developing diabetes, especially Type 2 diabetes.

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, he 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 blood glucose is 70 to 110 mg/dl. If your level is over 140 mg/dl, you may have diabetes.

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

See your doctor. Your doctor will perform tests to determine whether or not you have diabetes. If your blood sugar level is high, but not high enough to be considered diabetic, this is a condition called pre-diabetes. Your doctor will make recommendations to bring down your blood sugar level so that you can delay the development of Type 2 diabetes.

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