Diabetes: Frequently asked questions

Diabetes is usually a lifelong disease in which there is a high level of sugar in the blood. Diabetes affects more than 20 million Americans. In addition, over 40 million Americans have pre-diabetes. To understand diabetes, it is important to first understand the normal process by which food is broken down and used by the body for energy.

When food is digested, a sugar called glucose enters the bloodstream. Glucose is a source of fuel for the body. Then, an organ called the pancreas makes insulin. The role of insulin is to move glucose from the bloodstream into muscle, fat, and liver cells, where it can be used as fuel.

People with diabetes have high blood sugar because their body cannot move sugar into fat, liver, and muscle cells to be stored for energy. This is because their pancreas does not make enough insulin and/or their cells do not respond to insulin normally. After many years, diabetes can lead to other serious problems. These complications include: eye problems, painful sores and infections of the leg or foot, nerve damage, kidney problems, weakened immune system, and an increased risk heart attack or stroke.

What are the types of diabetes?

Type 1 diabetes

Type 1 diabetes accounts for about 5% of all diagnosed cases of diabetes. Type 1 is usually diagnosed in children and young adults, although it can occur at any time. People with type 1 diabetes must use insulin from an injection or a pump to manage their diabetes.

Type 2 diabetes

Type 2 diabetes accounts for about 95% of all cases diagnosed in adults. Several studies have shown that healthy eating, regular physical activity, and weight loss used with medication if prescribed, can help control complications from type 2 diabetes or can prevent or delay the onset of type 2 diabetes.

Gestational diabetes

Gestational diabetes is diagnosed in 2 to 10% of pregnant women. Gestational diabetes can cause health problems during pregnancy for both the child and mother. Children whose mothers had gestational diabetes have an increased risk of developing obesity and type 2 diabetes. Although gestational diabetes often goes away after pregnancy, about half of all women who have gestational diabetes get type 2 diabetes later in life.

What are the symptoms of diabetes?

  • Being very thirsty
  • Urinating often
  • Feeling very hungry
  • Feeling very tired
  • Losing weight without trying
  • Sores that heal slowly
  • Dry, itchy skin
  • Feelings of pins and needles in your feet
  • Losing feeling in your feet
  • Blurry eyesight

Some people with diabetes don’t have any of these signs or symptoms. The only way to know if you have diabetes is to have your doctor do a blood test.

How is diabetes diagnosed?

Urine analysis

A urine analysis may show high blood sugar. But a urine test alone does not diagnose diabetes. Your health care provider may suspect that you have diabetes if your blood sugar level is higher than 200 mg/dL. To confirm the diagnosis, one or more of the following tests must be done.

Blood tests

Fasting blood glucose test, hemoglobin A1c test, and oral glucose tolerance test are blood test that can be done to diagnose diabetes.


Screening for type 2 diabetes in people who have no symptoms is recommended for: overweight children who have other risk factors for diabetes (starting at age 10), overweight adults (BMI greater than 25) who have other risk factors, and adults over age 45.

What risk factors increase the likelihood of diabetes?

  • Being overweight or obese
  • Having a parent, brother, or sister with diabetes
  • Being African American, American Indian, Asian American, Pacific Islander, or Hispanic American/Latino heritage
  • Having a prior history of gestational diabetes or birth of at least one baby weighing more than 9 pounds
  • Having high blood pressure measuring 140/90 or higher
  • Having abnormal cholesterol with HDL ("good") cholesterol is 35 or lower, or triglyceride level is 250 or higher
  • Being physically inactive—exercising fewer than three times a week

What can be done to reduce the risk of diabetes?

Research has shown that the following lifestyle modifications can prevent, or at least delay the onset of type 2 diabetes among people at risk of diabetes:

  • Eating fewer high fat and high calorie foods
  • Losing at least 5%-7% of body weight (if overweight)
  • Being physically active for 150 minutes every week
Last reviewed: 
November 2016

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