Understanding Diabetes

Reviewed by Barbara Gordon, RDN, LD
Understanding Diabetes

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A whopping 30 million Americans have diabetes. And, even more people are unaware that they are at high risk for developing diabetes.

Diabetes affects the body's ability to make or properly use insulin. For people with diabetes, the pancreas makes insulin, but either it does not make enough of it or the body's cells don't use the insulin it makes.

Insulin is a hormone that your cells need to store and use energy from food. Insulin helps glucose, or sugar, enter the cells so they can use if for energy. If you have diabetes, glucose collects in the blood. Thus, your body is not getting the energy it needs. Also, the high levels of glucose circulate through the body, damaging cells along the way. Diabetes increases the risk of having a heart attack, stroke and kidney, eye and nerve damage.

Types of Diabetes

The causes of diabetes are complex and still not fully known. Sometimes diabetes is triggered by genetics, illness, being overweight or simply getting older. Although food doesn't cause diabetes, it is part of the strategy for managing the disease.

There are three main types of diabetes:

  • Type 1 Diabetes: The pancreas either makes no or too little insulin. Type 1 is an autoimmune disease that often begins in childhood. The onset is sudden. Just 5 percent of people with diabetes have Type 1. It cannot be prevented through diet or lifestyle.
  • Type 2 Diabetes: The pancreas does not make enough insulin or the body doesn't use the insulin it makes. Type 2 usually develops slowly. Eight out of ten people with this type of diabetes are overweight. Other risk factors include family history of diabetes, history of gestational diabetes, impaired glucose metabolism, older age and physical inactivity. African-Americans, Hispanic/Latino-Americans, American Indians, and some Asian-Americans and Native-Hawaiians or other Pacific Islanders are at a higher risk for Type 2 and its complications.
  • Gestational Diabetes: The cause is unknown. But, it is thought that hormones block the action of insulin. Gestational diabetes often goes away after the baby is born. However, women who develop this type of diabetes are at greater risk for Type 2 diabetes later in life.

How to Reduce Your Risk for Diabetes

You can prevent or delay Type 2 diabetes by making diet changes and being active. These steps also lower your risk for diabetes complications. Visit a registered dietitian nutritionist to learn about lifestyle changes that can reduce your risk for diabetes.

Signs, Symptoms and Testing

Signs and symptoms of diabetes include going to the bathroom frequently, being unusually thirsty, losing weight, feeling tired, irritability, blurred vision, frequent illness or infection and poor circulation such as tingling or numbness in the feet or hands. If you have these symptoms, see a doctor immediately. You may need to have one of the following tests for diabetes:

  • Fasting Plasma Glucose: The amount of glucose in a sample of blood taken when a person is fasting (not eating anything for eight to 12 hours; usually overnight).
  • HgA1c: Measures a person's average blood glucose range over the past two to three months. This test shows the amount of glucose that sticks to the red blood cell (hemoglobin; Hg).
  • Oral Glucose Tolerance Test: Results of this test are compared with standard non-diabetic results and show how the body uses glucose over time. This test is performed by a health care professional after an overnight fast. A blood sample is taken, the patient drinks a high-glucose beverage and then a blood sample is taken two hours later.

Managing Blood Glucose Levels

Once diagnosed, goals for managing diabetes include:

  • Keeping blood glucose levels within a normal range. Or, as close to normal as possible, which can prevent or reduce complications.
  • Reducing risk of heart disease and stroke, since people with diabetes are at risk for both.
  • Keeping blood pressure in normal ranges.
  • Working to get healthy cholesterol levels.
  • Taking steps to prevent, or at least slow, complications.

Whether you have been diagnosed with Type 1, Type 2 or gestational diabetes, the American Diabetes Association recommends the following blood glucose ranges:

  • 80 to 130 mg/dl (before a meal).
  • <180 mg/dl (1 to 2 hours after beginning a meal).
  • HgA1c 7% (average glucose over 3 months).

People with Type 1 diabetes need daily insulin injections or an insulin pump. People with Type 2 diabetes can help control blood sugar levels are through diet, physical activity and, for some people, a combination of medication and insulin injections.

General healthy eating tips to help manage diabetes include:

  • Limit foods that are high in added sugar.
  • Select smaller portions, spread out over the day.
  • Make your carbs count by choosing whole grains, fruit and vegetables over sugary drinks and refined, processed foods.
  • Enjoy a variety of whole-grain foods, fruits and vegetables every day.
  • Eat less saturated fat and focus on healthy fat sources such as avocados, olive and canola oil, and nuts.
  • Limit your consumption of alcohol.
  • Use less salt.

If you have been diagnosed with diabetes, an RDN can create a simple eating plan for you. This plan will take into account your medications, lifestyle and any other health problems. The expert advice of an RDN can help you manage your diabetes while ensuring you get the nutrients your body needs.

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