If any of these risk factors apply to you, talk to your doc about what you can do to prevent the disease.

By Kendall Wenaas
Photo by Getty Images

More than 30 million adults in the U.S. have diabetes—but 25% of them don’t know it. “There aren’t always symptoms,” says Sudipa Sarkar, MD, assistant professor of medicine at the Johns Hopkins University School of Medicine. “Oftentimes people with type 2 diabetes will have had the disease for years before they’re diagnosed.” But by being aware of the risk factors, you can better protect yourself from developing diabetes. While you can’t prevent type 1, there are a handful of risk factors for type 2 diabetes that you should be aware of:

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1. You have prediabetes.

More than 1 in 3 Americans have prediabetes, but 90% of these people don’t know they have it. A person with prediabetes has a blood sugar level above normal, but not high enough for the person to be considered diabetic. A fasting blood sugar level less than 100 mg/dL is normal, between 100-125 mg/dL is considered prediabetes and 126 mg/dL or above is considered diabetes. If your doctor has diagnosed you with prediabetes, adjusting your lifestyle can help prevent or at least delay type 2 diabetes.

2. Your family has a history of type 2 diabetes.

This puts you at higher risk of being diagnosed, but it doesn’t mean you’re automatically going to develop the condition. “You obviously can’t change your genetics, but being aware that it runs in your family can help you protect yourself,” Sarkar says. If diabetes runs in your family, talk to your doctor about steps you can take to prevent it.

3. You are overweight.

A BMI of 25 or higher (for example, a woman who is 5’5’’ and weighs over 150 pounds) could mean a person is at greater risk for developing diabetes.

4. You have high blood pressure.

A systolic blood pressure reading below 120 and a diastolic below 80 is considered normal. If yours falls outside this range, talk to your doctor about lifestyle changes to adopt and possible medications to take.

5. You are older than 45.

Blood sugar levels often get worst over time and can lead to type 2 diabetes later in life. “According to the American Diabetes Association, those who are age 45 or older should be screened, even if they don't have other risk factors,” Sarkar says.

6. You had gestational diabetes.

Gestational diabetes (when your body can’t make enough insulin while pregnant) occurs in roughly 10-25% of pregnancies in the U.S. If you had gestational diabetes while pregnant, you’re at higher risk of developing type 2 diabetes later on in life.

7. You are African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, Native Hawaiian or Pacific Islander.

According to the National Institutes of Health, these ethnicities are all at higher risk of developing type 2 diabetes.

What to Do

If one or more of these signs applies to you, talk to your doctor or a certified diabetes educator about making lifestyle changes to delay or reverse type 2 diabetes. You might consider avoiding sugar-sweetened beverages or adding moderate, regular exercise a couple times a week. “It’s hard to tell how much sugar and how many calories you’re consuming when you’re drinking something,” Sarkar says. “In general, the Mediterranean diet may be helpful in preventing diabetes. I also recommend filling your plate with non-starchy vegetables, like asparagus and broccoli.”