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According to the American Diabetes Association, more than 29 million children and adults in the United States have diabetes, and 8 million of them do not know that they have the disease. Many people think that diabetes is a condition that affects only older people, but in 2012, there were 1.7 million new cases of diabetes found in people 20 or older. Diabetes is a major risk factor for heart disease—in fact, two-thirds of people with diabetes die of some form of heart or blood vessel disease.

What is diabetes?

Diabetes is a condition where the body cannot make or respond properly to the hormone insulin. Your body needs insulin to change glucose ("blood sugar") into energy. With diabetes, your body cannot properly use the energy from the food you eat. When this energy transfer breaks down, the cells are damaged. Since the cells cannot take in glucose, the amount of glucose in your blood increases. Too much glucose in the blood is called "high blood sugar" or diabetes.

There are two major forms of diabetes: type 1 and type 2.

  • Type 1 or juvenile diabetes. This type of diabetes accounts for 5% of all cases of diabetes. Although it may occur at any age, type 1 diabetes usually begins early in life—during childhood or the teenage years. Type 1 diabetes occurs because the cells in the pancreas that make insulin are damaged. People with type 1 diabetes make little or no insulin to control their blood sugar levels, which means they must take insulin to stay alive.
  • Type 2 diabetes. This is the most common form of diabetes. It is usually diagnosed in people older than 20, but is increasingly occurring in children and young adults. People with type 2 diabetes can produce insulin, but it is either not enough or the body does not use it properly. Blood sugar levels usually can be controlled with diet and exercise. In a mild form, type 2 diabetes can go undetected for many years. If left untreated for too long though, it can lead to serious medical problems, including heart and blood vessel disease.

A form of type 2 diabetes called gestational diabetes affects about 4% of pregnant women and causes unusually high blood sugar levels during pregnancy. This type of diabetes can pose a risk to the unborn baby and needs to be managed throughout pregnancy. Even though blood sugar levels usually return to normal after giving birth, studies show that women who have had gestational diabetes have a 35-60% chance of developing type 2 diabetes in the next 10-20 years.

Who can get diabetes?

Although anyone can get diabetes, studies show that there is a hereditary link (the disease is passed down through family members). And since certain fats in the body interfere with insulin-glucose activity, anyone who is obese is at risk. Damage to the pancreas from hemochromatosis (an iron build-up in the body) can also lead to diabetes. You cannot get diabetes from eating too much sugar.

Because of their genetic makeup, people of American Indian, Alaskan Native, African American, and Hispanic descent are all at higher risk for diabetes.

Currently, there are 86 million people in the United States who have pre-diabetes. Pre-diabetes is a condition in which blood sugar levels are higher than normal but not high enough to be full-blown diabetes. The American Diabetes Association now recommends that obese people over the age of 45 be screened for pre-diabetes. Obese people younger than 45 should be screened if they have other risk factors for diabetes. Most people with pre-diabetes usually develop type 2 diabetes within 10 years.

What are the risks?

Diabetes weakens the body's ability to fight infection and heal wounds, so infections last longer and wounds are slower to heal. People with diabetes are more likely to have foot problems, heart and kidney disease, and a type of gum disease (called periodontal disease) that can lead to tooth loss. Diabetes can also lead to blindness.

A survey on behalf of the American Diabetes Association found that 68% of people with diabetes did not know that heart disease and stroke are a serious threat to their health. Even if their blood sugar levels are under control, diabetes still increases the risk of heart disease and stroke. Part of the reason for this is that diabetes affects cholesterol and triglyceride levels. Usually people with diabetes also have high blood pressure and are obese, which increases their risk even more.

What are the symptoms?

With type 1 diabetes, high blood sugar levels develop quickly. Symptoms may include increased thirst and hunger, weight loss, and frequent urination.

In the early stages of type 2 diabetes, there are often no symptoms. If the person does have symptoms, they may include thirst, frequent urination, weight loss, and blurry eyesight. Many people do not even notice these symptoms or they simply think they are a result of getting older. In most cases of type 2 diabetes, the disease is discovered through a routine visit to the doctor.

How is diabetes diagnosed?

Diabetes is diagnosed by a blood test that measures the glucose levels in the blood. The test is done after you have fasted (no eating or drinking anything but water) for 8 to 12 hours the night before.

An oral glucose tolerance test may be helpful in diagnosing type 2 diabetes. You must fast the night before this test as well. Doctors have you drink a glucose liquid. Blood and urine tests are performed before and after you drink the glucose solution to measure your glucose levels. Be sure to tell your doctor about all of the medicines you are taking because certain medicines can interfere with test results.

If the levels of glucose are higher than 140 mg for every tenth of a liter of blood, you have diabetes. This amount of glucose is about the same as dissolving 3 tiny grains of sugar in a large glass of water.

How is diabetes treated?

When diabetes is detected, a doctor may prescribe a change in your diet as well as weight loss and exercise programs. Medicines can also be used to control your blood sugar.

  • There is no way to prevent type 1 diabetes. For people with type 1 diabetes, treatment includes a special diet and regular exercise. Patients must monitor their blood sugar levels using a blood sugar meter. They must also take insulin.
  • For people with type 2 diabetes, treatment may include a special diet and an exercise program. If diet and exercise do not help to control blood sugar levels, medicines may be prescribed. In some cases, people with type 2 diabetes need to take insulin as well.

It is very important that people with diabetes have regular check-ups, control their weight and cholesterol, follow an exercise program, lower high blood pressure, and not smoke. If you know that you have diabetes, you should already be under the care of a doctor. If you think that you have diabetes but are not sure, see your doctor for tests.

See also on this site:

See on other sites:

Diabetes Type 2

The American Diabetes Association
Living with Diabetes - Complications - Heart Disease

The American Heart Association

The National Diabetes Information Clearinghouse (NDIC) 
Diabetes, Heart Disease and Stroke

Updated January 2015
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