Clinical trial
Diabetes Prevention Program (DPP)
Last updated Sat May 30 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
Design
Randomised 3,234 US adults with impaired glucose tolerance (pre-diabetes) to:
- Intensive lifestyle (7% weight loss + 150 min/week moderate exercise).
- Metformin 850 mg twice daily.
- Placebo.
Mean follow-up 2.8 years.
Findings
- Lifestyle: 58% reduction in T2D incidence vs placebo.
- Metformin: 31% reduction vs placebo.
- Lifestyle effect bigger in older participants; metformin effect bigger in younger / more obese.
- Subsequent DPP Outcomes Study showed lifestyle benefits persist after the active intervention ends — over 15 years cumulative T2D was still 27% lower vs placebo.
Why it matters
DPP established the gold standard for type-2 diabetes prevention. The 7% weight-loss target + 150 min exercise prescription is now embedded in CDC guidelines (National DPP), insurance coverage in the US, and similar programmes globally.
Scaling
National DPP has been adapted to be delivered by community organisations and via apps (Omada, Noom Diabetes Prevention) with demonstrated real-world effectiveness, though typically smaller effect sizes than the original trial.
Related entries
References
- Knowler, W. C. et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N. Engl. J. Med. 346, 393–403 (2002).