When it comes to preventing type 2 diabetes, healthy habits still win.
More than two decades after the U.S. Diabetes Prevention Program (DPP) first launched, researchers have completed a long-term follow-up — and the results are clear: Lifestyle changes, including modest weight loss and regular physical activity, outperformed the diabetes drug metformin in preventing disease onset over the long haul.
The original DPP study, launched in 1996, enrolled more than 3,200 people with prediabetes. Participants were randomly assigned to one of three groups: a lifestyle intervention, metformin or placebo. After just three years, the lifestyle group had a 58% lower risk of developing diabetes compared to placebo, and the metformin group had a 31% reduction — strong enough that researchers ended that phase of the trial early.
But what about the long-term effects?
In the newly published 22-year follow-up, the lifestyle group maintained a longer delay in diabetes onset — a median of 3.5 extra years without diabetes, compared to 2.5 years for those taking metformin.
And for many, the benefits endured: “The data suggests that those people who didn't get diabetes also didn't get diabetes after 22 years,” said study co-author Vallabh “Raj” Shah of the University of New Mexico.
Researchers say these findings are especially important because they reinforce the power of early intervention. Even modest changes — like walking 30 minutes a day and improving your diet — can have long-term benefits that medication alone can’t match.
Originally designed to compare diabetes prevention strategies, the DPP Outcomes Study is now also being used to study aging-related conditions like cancer and dementia. But for now, it offers a clear reminder: food and movement matter. And their benefits last.
The study, published in The Lancet Diabetes & Endocrinology, was funded by the U.S. National Institute of Diabetes and Digestive and Kidney Diseases, along with other federal agencies.