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What Is Diabetes Mellitus Type 1?

Diabetes mellitus type 1 (or just diabetes) is a lifelong disorder that prevents the body from getting energy from food. The body doesn’t make enough insulin, a hormone produced by special beta cells in the pancreas. Insulin is vital because it controls the amount of sugar (glucose) that body cells get from the blood. People with diabetes have too much sugar in the blood, and not enough sugar getting into body cells.

Slightly more men than women have type 1 diabetes. It often starts at ages 12 to 15 years, with most cases diagnosed before age 30. More than 300,000 people in the United States have type 1 diabetes.

What Causes Diabetes?

Not enough insulin is the cause. In most diabetic people, the body’s own defense, the immune (infection-fighting) system, destroys beta cells in the pancreas, but the reason for this isn’t fully known. Other rarer causes are certain diseases, such as cystic fibrosis, which affects the pancreas, and surgical removal or severe inflammation (swelling, irritation) of the pancreas.

What Are the Symptoms of Diabetes?

Diabetes warning signs include urinating often, feeling very thirsty, getting frequent infections, losing weight quickly, and feeling tired and weak. Symptoms of uncontrolled diabetes also include blurred vision or blindness, slow-healing skin sores, numbness in hands or feet, and worsening kidney function.

In diabetic ketoacidosis, another complication of diabetes, substances (ketones) accumulate. Ketones in the blood make the blood dangerously acidic, which affects multiple organs including the brain and can be life-threatening, if not rapidly diagnosed and treated in the hospital.

How Is Diabetes Diagnosed?

For diagnosis, the health care provider uses a medical history, physical examination, and measurements of blood sugar. These tests include fasting and nonfasting levels, average glucose levels during 2 to 3 months (hemoglobin A1c [HbA1c] test), and glucose tolerance test. The health care provider may also do blood and urine kidney tests and measure blood fat (lipid) level.

How Is Diabetes Treated?

A special diet will help control blood sugar. A nutritionist can help manage this diet. Blood sugar levels need checking often, which can be done with a glucometer. People must watch for signs that the blood sugar level is too high or too low. Insulin injections are given at home, usually two or three times daily. The health care provider can explain how to give them.

The health care provider will suggest exercises to help control blood sugar levels.

Regular foot care and eye checkups are needed to prevent complications.

DOs and DON’Ts in Managing Diabetes Mellitus:

  • DO follow your special diet and eat snacks at the same time every day.
  • DO get enough exercise and sleep.
  • DO check your blood sugar level if you’re sick. Call your health care provider if you have fever, nausea, or vomiting and can’t keep down solids or liquids.
  • DO call your health care provider if your blood sugar level is too high.
  • DO go to the hospital right away if you have a seizure, can’t wake up, or lose consciousness.
  • DO follow your doctor’s orders about insulin exactly.
  • DON’T smoke or use alcohol. They can affect blood sugar levels and make diabetes worse.
  • DON’T eat food with high sugar content.
  • DON’T use more insulin than your health care provider recommends, it can lower your sugar to a dangerous level.
  • DON’T get dehydrated.
  • DON’T eat foods that your health care provider or dietitian doesn’t suggest.

Contact the following sources:

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

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

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