A study which began in 1996 of 3,234 people with prediabetes randomly assigned them to groups which were either given metformin, given intensive lifestyle (nutrition and physical activity) counseling or a placebo, found good news. Three years later, the risk of developing type 2 diabetes was reduced by 58% with lifestyle counseling and 31% with metformin. Two decades later, 2,425 are still alive and being followed. The diabetes risk remains lower than the placebo group by 25% in the original lifestyle group and by 18% in the metaformin group. Although metformin isn’t approved for prediabetes treatment, your doctor can still prescribe it off label. The American Diabetes Association recommends it for people with prediabetes who are at high risk of developing type 2 diabetes.