Washington: A groundbreaking long-term study spearheaded by the George Washington University Biostatistics Center has shown that lifestyle interventions and metformin significantly reduce the risk of developing type 2 diabetes, even 21 years after the interventions began.
This follow-up to the landmark U.S. Diabetes Prevention Program (DPP), known as the Diabetes Prevention Program Outcomes Study (DPPOS), is the first to provide concrete evidence of the enduring benefits of diabetes prevention strategies across decades.
Originally launched in 1996, the DPP recruited 3,195 adults at high risk for diabetes, with nearly half identifying as members of U.S. minority groups disproportionately affected by the disease. Participants were divided into three groups: one receiving intensive lifestyle intervention, one taking daily metformin (a common diabetes medication), and one receiving a placebo. The original study found dramatic short-term benefits, including a 58% reduction in diabetes incidence for the lifestyle group and a 31% reduction for those on metformin.
Now, more than two decades later, the DPPOS confirms that those early interventions continue to yield significant health dividends. Participants who adopted lifestyle changes experienced a 24% reduced risk of developing diabetes over 21 years, while those taking metformin saw a 17% reduction. Even more strikingly, the median time participants remained diabetes-free was extended by 3.5 years in the lifestyle group and by 2.5 years in the metformin group compared to the placebo.
“This research affirms what we've suspected for years: prevention pays off, and it pays off big—especially when started early and maintained,” said Lynn Goldman, Dean of GW’s Milken Institute School of Public Health. “In the face of a disease that has more than doubled in prevalence over the last three decades, these findings offer real hope.”
Diabetes, particularly type 2, is a chronic condition that leads to serious complications, including kidney failure, cardiovascular disease, blindness, and amputations. Preventing its onset not only prolongs life but also improves its quality, reduces healthcare costs, and mitigates the burden on families and public health systems.
The GW Biostatistics Center played a critical role in coordinating the DPP and DPPOS studies, managing data and collaborating with researchers from the National Institutes of Health (NIH) and 28 clinical centers nationwide. Marinella Temprosa, lead biostatistician and associate research professor at GW, credited the long-term success of the trials to the commitment of participants and institutions over the years.
Both studies were funded by the NIH’s National Institute of Diabetes and Digestive and Kidney Diseases, with the National Institute on Aging supporting further research into whether lifestyle changes may also reduce the risk of age-related diseases such as Alzheimer’s and cancer.
“The federal investment in long-term clinical research has been instrumental in uncovering life-saving insights like these,” Goldman noted. “This is not just a win for science—it’s a win for the millions of people who can now live longer, healthier lives free from diabetes.”
The results, published April 28 in The Lancet Diabetes & Endocrinology, underscore the effectiveness of early, evidence-based prevention strategies and have already informed national and global diabetes prevention programs modeled on the DPP.
As America continues to grapple with the diabetes epidemic, the DPPOS provides a resounding message: prevention works, and it works for the long haul.
