- To know if you have prediabetes, it’s important to get your blood sugar levels checked and recognise several key risk factors.
- Take our prediabetes risk test to determine whether you’re at significant risk for prediabetes.
- This article was medically reviewed by Jason R. McKnight, MD, MS, a family medicine physician and clinical assistant professor at Texas A&M College of Medicine.
- Visit Insider’s Health Reference library for more advice.
According to the Centres for Disease Control and Prevention (CDC), more than 33% of US adults (about 88 million) have prediabetes, but 84% of them do not know they have it.
Prediabetes is the precursor to type 2 diabetes. It is when your blood sugar is higher than normal, but not yet at the level of type 2 diabetes.
Without treatment or lifestyle modifications, about 15% to 30% of people with prediabetes will get type 2 diabetes within five years, according to the New York State Department of Health.
Luckily, it is possible to prevent the progression from prediabetes to type 2 diabetes with certain lifestyle changes, like exercising more, eating healthier foods, and sometimes taking medication.
Here’s what you should know about how to recognise prediabetes and prevent type 2 diabetes.
Take the prediabetes risk test
Editor’s note: This quiz was developed based off the CDC’s Prediabetes Risk Test.
Causes and risk factors
Like type 2 diabetes, prediabetes occurs when your body does not process insulin properly. Insulin is a hormone that the pancreas releases to help regulate the amount of sugar in your blood.
There are certain factors that can put you at higher risk for prediabetes, such as:
- Weight. This is the main risk factor for diabetes. Your Body Mass Index (BMI) tells you whether you are underweight, overweight, or healthy by comparing your height and weight. A BMI in the overweight or obese category puts you at greater risk for diabetes.
- Waist size. A larger waist can also make it difficult for cells to absorb insulin. Men with waists larger than 40 inches and women with waists larger than 35 inches are at higher risk for prediabetes. In particular, the more fat you carry around the abdomen, the more trouble your cells have processing insulin.
- Diet. Eating high amounts of refined carbohydrates, like white bread and pasta, can spike your blood sugar. An unhealthy diet can also cause you to gain more fat, which contributes to insulin resistance.
- Sedentary lifestyle. Exercise is an important way of controlling weight and increasing insulin sensitivity. The more sedentary you are, the higher your chances of getting prediabetes.
- Age. Prediabetes can develop at any age, but the risk increases above age 45. According to the National Council for Ageing Care, that’s because older people have been eating for longer and are exposed to more sugar.
- Race. African Americans, Hispanics, Native Americans, Asian Americans, and Pacific Islanders are at higher risk than white Americans. While the exact reason for this is unknown, Justin B. Echouffo Tcheugui, MD, PhD, assistant professor at Johns Hopkins School of Medicine, says this is partially caused by socioeconomic inequality, though genetics, standard diet, and access to medical care can all contribute.
- Family history. If you have a parent who developed type 2 diabetes before the age of 50, you have a 1 in 7 chance of getting it. Your risk is 1 in 13 if your parent was diagnosed after 50. Almost all type 2 diabetics started with prediabetes.
- Gestational diabetes. About 50% of women who experience diabetes while pregnant – a condition called gestational diabetes – will develop type 2 diabetes after pregnancy. If a mother with a history of gestational diabetes develops type 2, their child has a 2% to 4% chance of getting it later in life.
According to the CDC, there are several tests your doctor can use to find out if you have prediabetes or type 2 diabetes:
- A1C test. This test calculates your average blood sugar level over the course of 3 months. An A1C between 5.7 and 6.4% means you have prediabetes.
- Fasting blood sugar test. This test checks your blood sugar after not eating for eight hours (it’s best to do it in the morning when you wake up). A blood sugar level of 100 to 125 mg/dL means you have prediabetes.
- Glucose tolerance test. After fasting overnight, doctors will take your blood sugar level before and after consuming a sugary drink. After 2 hours, a blood sugar level of 140 to 199 mg/dL means you have prediabetes.
Echouffo Tcheugui says most people do not know they have prediabetes because it is usually asymptomatic, meaning there are no signs or symptoms.
Typically, people with prediabetes don’t show symptoms until they already have type 2 diabetes. If your prediabetes has already progressed, you might experience further signs of diabetes, such as:
- Increased hunger or thirst levels
- Frequent urination
- Blurry vision
However, since most people with prediabetes show no symptoms, it’s important to check your blood sugar during your yearly doctor’s visit.
If you are diagnosed with prediabetes, it doesn’t mean you’ll automatically progress to type 2 diabetes. With the right treatment, prediabetes is reversible. Echouffo Tcheugui says there are two main treatment options for prediabetes: lifestyle changes and medication.
Changing your lifestyle to include healthier habits can help prevent progression to type 2 diabetes by decreasing your risk factors. Examples of healthy habits include:
- A healthy diet low in simple carbohydrates like white bread can help prevent the onset of type 2 diabetes. Doctors recommend focusing your diet around vegetables, whole grains, and healthy proteins.
- The CDC advises fitting in 150 minutes of moderate physical activity per week, like walking, swimming, or cycling.
- If you are overweight, getting into a healthy weight range is the best way to treat prediabetes. The CDC says that losing just 5-7% of body weight can have a big impact.
The medication metformin is commonly prescribed to treat prediabetes. Metformin helps your body process insulin and lower your blood sugar levels. However, metformin may not be suitable for some people, such as those with kidney problems.
The Diabetes Prevention Program (DPP) was a highly successful intervention program conducted in the US for 3,234 participants with prediabetes. In the study, published in the journal Diabetes Care in 2002, taking metformin alone reduced the risk of developing type 2 diabetes by 31%, and lifestyle changes alone, including weight loss and physical activity goals, reduced risk by 58%.
While the study found that lifestyle changes were a superior treatment option to medication, metformin was particularly effective for younger and more obese patients.
The bottom line
Prediabetes is a serious health condition and often leads to type 2 diabetes if left untreated. The good news is prediabetes can be reversible with lifestyle changes and medication.
It’s important to be aware of the risk factors for prediabetes and get tested if you think you might be at risk. If you have prediabetes, consult your doctor to come up with the best treatment plan.