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What Is Diabetes Mellitus Type 2?

Diabetes mellitus type 2, or type 2 diabetes (abbreviated DM), is one type of diabetes. In DM, a problem with insulin prevents body cells from using sugar (glucose) in food. Insulin is a chemical made by the pancreas. Insulin helps sugar enter body cells, which use the sugar for energy. DM involves poor responses of cells to insulin (insulin resistance) in type 2 DM, lack of insulin in type 1 DM, and too much sugar in the blood (hyperglycemia) in both types of DM.

People of any age can have DM. Type 2 DM occurs more often in overweight adults, especially those with diabetic relatives. DM is a lifelong illness.

Another name for type 2 DM is adult-onset diabetes.

What Causes Type 2 Diabetes?

In DM, when cells don’t have or don’t respond to insulin, they can’t get the sugar. Sugar stays in the blood until some extra sugar goes into urine and is removed. Too much blood sugar damages blood vessels, which can cause serious diseases.

What Are the Symptoms of Type 2 Diabetes?

Symptoms start slowly but get worse, although some people have no symptoms. Some people complain of often being thirsty and hungry and may need to urinate often.

More symptoms are tiredness, blurred vision, chest pain or other heart trouble, weight gain or loss, foot ulcers, numbness or tingling in hands or feet, sores that don’t heal, infections, and impotence (in men).

Serious complications of long-term DM include blindness, kidney failure, nerve damage, coronary heart disease, and peripheral vascular disease.

How Is Type 2 Diabetes Diagnosed?

The health care provider uses a medical history, physical examination, and blood sugar levels for diagnosis.

Other laboratory tests include average sugar levels during 2 to 3 months (hemoglobin A1C [HbA1c] test) and glucose tolerance test. The health care provider will also test the kidneys with blood and urine tests and the blood fat (lipid) level.

How Is Type 2 Diabetes Treated?

Many people control DM through just diet and exercise. New diet rules allow many food choices, but avoiding high-sugar and high-fat foods is important. Exercise helps control weight and keep blood sugar level down, and the body uses insulin better.

Some people need medicine, however. Medicine for type 2 DM usually consists of pills to help the body use sugar. If the pills don’t work, insulin is given by injection.

Blood sugar levels must be tested often (usually at least daily). Being under the care of specialists (endocrinologist, podiatrist, eye health care provider) in addition to your primary care health care provider can also help prevent complications from diabetes.

DOs and DON’Ts in Managing Diabetes Mellitus Type 2:

  • DO keep your blood sugar level near normal.
  • DO exercise regularly.
  • DO keep to a normal body weight.
  • DO eat regular meals.
  • DO eat healthy: whole-grain foods, fruit, vegetables, and high-quality proteins. Avoid high-sugar, high-fat, and white flour foods.
  • DO keep alcohol intake low.
  • DO have your eyes checked yearly and visit the dentist twice yearly.
  • DO quit smoking.
  • DO take good care of your feet. Visit your podiatrist at least twice per year.
  • DO call your health care provider if you have a fever or vomiting and cannot eat or drink.
  • DO call your health care provider if you have high or low blood sugar levels that you cannot explain.
  • DON’T smoke.
  • DON’T drink liquor or high-sugar liquids.

Contact the following sources:

  • National Diabetes Information Clearinghouse
    Tel: 1-800-860-8747
  • American Diabetes Association
    Tel: 1-800-DIABETES (1-800-342-2383)

Copyright © 2016 by Saunders, an imprint of Elsevier, Inc.

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