Alex Ehsan, MD, PhD · Medical search

Diabetes

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

What is diabetes?

Diabetes, also known as diabetes mellitus, is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose is your body's main source of energy. Your body can make glucose, but it also comes from the food you eat. Insulin is a hormone made by your pancreas. Insulin helps move glucose from your bloodstream into your cells, where it can be used for energy.

If you have diabetes, your body can't make insulin, can't use insulin as well as it should, or both. Too much glucose stays in your blood and doesn't reach your cells. This can cause glucose levels to get too high. Over time, high blood glucose levels can lead to serious health conditions. But you can take steps to manage your diabetes and try to prevent these health problems.

What are the types of diabetes?

There are different types of diabetes:

What causes diabetes?

The different types of diabetes have different causes:

Who is more likely to develop diabetes?

The different types of diabetes have different risk factors:

What are the symptoms of diabetes?

The symptoms of diabetes may include:

But it's important to know that your symptoms may vary, depending on which type you have:

How is diabetes diagnosed?

To find out if you have diabetes, your health care provider will use one or more glucose blood tests. There are several types, including the A1C test.

What are the treatments for diabetes?

Treatment for diabetes involves managing your blood glucose levels:

Checking your blood glucose levels is also an important part of managing your diabetes. Ask your provider about the best way to check your blood glucose level and how often you should check it.

Can diabetes be prevented?

Type 1 diabetes can't be prevented.

You may be able to delay or prevent type 2 diabetes through the same lifestyle changes that are used to manage diabetes (eating a healthy diet, staying at a healthy weight, and getting regular physical activity). These lifestyle changes may also help prevent gestational diabetes.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

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