Can prediabetes be reversed?
Written and medically reviewed by Zahraa Sater, M.D., M.P.H.
Reviewed August 12, 2026 · Next review due August 12, 2028
Short answer
Prediabetes can often be pushed back toward normal glucose, and progression to type 2 diabetes can be delayed for decades. In the Diabetes Prevention Program, a lifestyle program targeting 7 percent weight loss and 150 minutes of activity a week cut new diabetes by 58 percent over 2.8 years, and metformin cut it by 31 percent.
Prediabetes responds to treatment better than almost anything else in endocrinology. The Diabetes Prevention Program randomized 3,234 adults at high risk and followed them for an average of 2.8 years. Diabetes developed in 11.0 cases per 100 person years on placebo, 7.8 on metformin, and 4.8 in the lifestyle group: a 58 percent reduction with lifestyle and 31 percent with metformin.
What the lifestyle arm actually did
The Diabetes Prevention Program lifestyle goal was modest and specific: lose at least 7 percent of body weight and do at least 150 minutes of physical activity a week, supported by structured coaching. There was no elimination of carbohydrates, no fasting protocol and no supplement. For a person weighing 200 pounds, 7 percent is 14 pounds. That is the scale of change that produced the largest effect ever shown in diabetes prevention.
Does the benefit last
Yes, though it narrows. In the Diabetes Prevention Program Outcomes Study, at 15 years the original lifestyle group still had a 27 percent lower rate of diabetes than placebo. After an average of 22 years of follow up, the reduction was 25 percent for the lifestyle group and 18 percent for metformin. Participants who never developed diabetes also had a 39 percent lower risk of major cardiovascular endpoints.
| Intervention | Effect at about 3 years | Effect at about 22 years |
|---|---|---|
| Structured lifestyle program | 58 percent lower incidence | 25 percent lower incidence |
| Metformin 850 mg twice daily | 31 percent lower incidence | 18 percent lower incidence |
Where metformin fits
Metformin is an option, not a default, in prediabetes. The ADA Standards of Care support considering it in higher risk adults, and in the Diabetes Prevention Program it worked best in younger participants, those with higher BMI and women with previous gestational diabetes. It was less effective than the lifestyle program in every long term analysis. Metformin also does not remove the reason for asking about sleep, activity, alcohol and medications that raise glucose.
A workable plan looks like this: a defined weight target of 5 to 7 percent of current body weight, 150 minutes a week of moderate activity plus two resistance sessions, a repeat A1C and fasting glucose in six months, and an honest look at sleep and any glucose raising medication. If the numbers are not moving by six months, that is the point to discuss metformin rather than the first visit.
The clinical detail
Diabetes Prevention Program lifestyle participants aimed for at least 7 percent weight loss and at least 150 minutes weekly of moderate physical activity. Number needed to treat over three years to prevent one case was 6.9 for lifestyle and 13.9 for metformin. The 2026 ADA Standards of Care recommend a weight loss target of 5 to 7 percent of baseline body weight in people with prediabetes and identify Mediterranean and lower carbohydrate eating patterns as having the strongest evidence for preventing or delaying type 2 diabetes.
Metformin for prevention is generally 850 mg twice daily as used in the trial. Long term metformin can lower vitamin B12, and the ADA advises periodic assessment of B12 in metformin treated people, particularly those with anemia or peripheral neuropathy.
Written and medically reviewed by Zahraa Sater, M.D., M.P.H.
Reviewed August 12, 2026 · Next review due August 12, 2028
Sources
- Reduction in the Incidence of Type 2 Diabetes with Lifestyle Intervention or Metformin. New England Journal of Medicine. PMID 11832527
- Diabetes Prevention Program (DPP). National Institute of Diabetes and Digestive and Kidney Diseases
- New Data from the Diabetes Prevention Program Outcomes Study, 22-year follow-up. American Diabetes Association
- 3. Prevention or Delay of Diabetes and Associated Comorbidities: Standards of Care in Diabetes 2026. American Diabetes Association. PMID 41358891
This library is educational and is not individual medical advice. Read our Editorial and Medical Review Policy.