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Type 2 diabetes: An introduction

Millions of people in the United States have diabetes. It's so common that if you don't have it, you probably know someone who does.

Most people who have diabetes have type 2. Like other forms of diabetes, it's a serious, lifelong condition that can lead to heart disease, kidney failure and blindness.

Fortunately, you can take steps to avoid or at least delay the onset of the disease and to protect yourself from the complications it can cause.

Type 2 diabetes: Trouble using insulin

Type 2 diabetes happens when the body doesn't properly use insulin—a hormone that transports glucose (sugar) from the blood to the cells where it is used for fuel—or doesn't make enough. As a result, unused glucose builds up in the blood.

You're more likely to get type 2 diabetes as you get older (though the disease can affect people of all ages). It's also more likely among certain ethnic groups, such as African Americans, Hispanics, American Indians, Asian Americans and Pacific Islanders.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), these factors also raise your risk:

  • Having a family history of type 2 diabetes.
  • Being overweight.
  • Being physically inactive.
  • Having a history of gestational diabetes.
  • Having prediabetes. In this condition, blood glucose levels are higher than normal but not high enough for a diagnosis of diabetes.

Type 2 diabetes used to be rare in children. In fact, it used to be called adult-onset diabetes. But as more young people become overweight, it is now more common for them to develop this disease.

Symptoms begin slowly

Type 2 diabetes doesn't always cause symptoms. But according to the NIDDK, when symptoms do occur they tend to begin slowly and may include:

  • Feeling tired much of the time.
  • Frequent urination.
  • Increased thirst and hunger.
  • Unexplained weight loss.
  • Blurred vision.
  • Slow healing of wounds or sores.

If you have symptoms of diabetes, see your doctor. Several tests that measure your blood glucose can check for the disease.


The complications of diabetes can affect almost every part of the body. That's why it's important to find the disease early on and take steps to control it.

According to the NIDDK, if not controlled, diabetes can:

  • Nearly double your risk of having heart disease or stroke.
  • Cause nerve damage, which may cause you to lose feeling in your feet or have painful burning in your feet. If you can't feel your feet, you may not notice sores or injuries.
  • Lead to poor circulation. As a result, injuries on your feet may not heal and could become infected. In severe cases amputation may be necessary.
  • Cause kidney failure.
  • Cause eye problems that can lead to blindness.

Controlling the disease

People with type 2 diabetes can do a lot to manage it and avoid complications. Management strategies are aimed at controlling blood glucose, cholesterol and blood pressure.

According to the Centers for Disease Control and Prevention and the NIDDK, these steps can help:

  • Follow a healthy meal plan. A dietitian can help you develop a diet that includes fruits and vegetables, whole grains, nonfat dairy products, lean meats and fish. It's also important to limit the amount of salt you consume.
  • Be as active as possible. Try to exercise at least 30 minutes a day, almost every day.
  • Maintain a healthy weight. If you're carrying too many pounds, losing just 5% to 7% of your body weight can help you avoid diabetes. Weight loss can also help people who already have diabetes keep it under control.
  • Don't smoke.
  • Check your blood sugar regularly.
  • Take your medicine as prescribed. Insulin and other medications may be necessary to help you control your blood glucose.
  • Work closely with your healthcare team. You'll need regular exams to check your eyes, blood pressure and cholesterol, among other things. You'll also need regular A1C tests to check your average blood glucose over several months.

Learn more

For more information, visit the Diabetes health topic center.

Reviewed 3/5/2023

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