Diabetes Basics

Key points

  • Diabetes is a chronic (long-lasting) health condition that affects how your body turns food into energy.
  • There are three main types of diabetes: type 1, type 2, and gestational diabetes (diabetes while pregnant).
Diabetes and related words with a stethoscope


Your body breaks down most of the food you eat into sugar (glucose) and releases it into your bloodstream. When your blood sugar goes up, it signals your pancreas to release insulin. Insulin acts like a key to let the blood sugar into your body's cells for use as energy.

With diabetes, your body doesn't make enough insulin or can't use it as well as it should. When there isn't enough insulin or cells stop responding to insulin, too much blood sugar stays in your bloodstream. Over time, that can cause serious health problems, such as heart disease, vision loss, and kidney disease.

There isn't a cure yet for diabetes, but losing weight, eating healthy food, and being active can really help. Other things you can do to help:


Type 1 diabetes

Type 1 diabetes is thought to be caused by an autoimmune reaction (the body attacks itself by mistake). This reaction stops your body from making insulin. If you have type 1 diabetes, you’ll need to take insulin every day to survive. Currently, no one knows how to prevent type 1 diabetes. Type 1 diabetes is usually diagnosed in children and young adults but can be diagnosed at any age, and symptoms often develop quickly.

Keep Reading: About Type 1 Diabetes

Type 2 diabetes

With type 2 diabetes, your body doesn’t use insulin well and can’t keep blood sugar at normal levels. It develops over many years and is usually diagnosed in adults (but more and more in children, teens, and young adults). You may not notice any symptoms, so it's important to get your blood sugar tested if you're at risk.

Keep Reading: About Type 2 Diabetes

Gestational diabetes

Gestational diabetes develops in pregnant women who have never had diabetes. If you have gestational diabetes, your baby could be at higher risk for health problems. Gestational diabetes usually goes away after your baby is born. However, it increases your risk for type 2 diabetes later in life. Your baby is more likely to have obesity as a child or teen and develop type 2 diabetes later in life.



In the United States, about 1 in 3 adults has prediabetes. More than 8 in 10 people with prediabetes don't know they have it. With prediabetes, blood sugar levels are higher than normal, but not high enough for a type 2 diabetes diagnosis. Prediabetes raises your risk for type 2 diabetes, heart disease, and stroke.

Prediabetes and type 2 diabetes can be prevented with lifestyle changes. Currently, no one knows how to prevent type 1 diabetes.

How you can prevent type 2 diabetes‎

If you have prediabetes, learn how the lifestyle change program can help you take healthy steps to prevent or delay type 2 diabetes.

Diabetes by the numbers

Graphic Text Diabetes - A US Report Card Diabetes about diabetes. Stats are listed below.
In the last 20 years, the number of adults diagnosed with diabetes has more than doubled.

In the United States:

  • About 38 million adults have diabetes, and 1 in 5 of them don't know they have it.
  • Diabetes is the eighth leading cause of death.
  • Type 2 diabetes accounts for about 90% to 95% of all diagnosed cases of diabetes; type 1 diabetes accounts for about 5% to 10%.
  • Diabetes is the No. 1 cause of kidney failure, lower-limb amputations, and adult blindness.
  • In the last 20 years, the number of adults diagnosed with diabetes has more than doubled.
  • Medical costs and lost work and wages for people with diagnosed diabetes total $413 billion yearly.
  • Medical costs for people with diabetes are more than twice as high as for people who don't have diabetes.


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