According to the CDC, prediabetes means your blood sugar levels are higher than normal but not high enough for a diagnosis of type 2 diabetes. A test of your average blood sugar reading over a three-month period will indicate that you have a hemoglobin A1C of 5.7 to 6.4 percent, or a fasting blood glucose level between 100 to 125 mg/dL.
Undetected or ignored, prediabetes can develop into diabetes within a few years. The good news is that if you have it, lifestyle changes such as a "proper eating plan that enables weight loss, and daily exercise, can work as well as or better than the use of medications," says Marvin M. Lipman, M.D., Consumer Reports' chief medical adviser.
In the landmark Diabetes Prevention Program (DPP) study, people with prediabetes who lost 7 percent of their body weight by eating less fat, consuming fewer calories, and exercising for 150 minutes per week had a 58 percent reduced risk of diabetes after three years. Participants taking metformin reduced their risk of developing diabetes by 31 percent.
And a 2015 a follow-up to the DPP study found that after 15 years, regular exercise plus a low-calorie, low-fat diet continued cutting the incidence of developing type 2 diabetes by 27 percent for people with prediabetes; metformin lowered it by 18 percent.