In the early 2000s, the U.S. Diabetes Prevention Program (DPP), a large randomized clinical trial, revealed that intensive lifestyle modification was more effective than the diabetes medication metformin at preventing at-risk patients from developing Type 2 diabetes. A recent follow-up study has now shown that the health benefits from lifestyle intervention can last for more than 20 years.
The study, published in The Lancet Diabetes & Endocrinology, was led by a team including Vallabh “Raj” Shah, professor emeritus in the Departments of Internal Medicine and Biochemistry & Molecular Biology at The University of New Mexico School of Medicine. Shah noted that the most significant improvements occurred in the first few years of the study and remained durable over time. “The data suggests that those people who didn’t get diabetes initially also didn’t develop it after 22 years,” he said.
The DPP, launched in 1996, aimed to compare the benefits of metformin—then newly approved by the FDA—with a structured lifestyle modification program focusing on exercise, healthy eating, and moderate weight loss. The trial enrolled 3,234 patients with prediabetes across 30 institutions in 22 states.
Results showed that the intensive lifestyle intervention reduced diabetes development by 24%, while metformin achieved a 17% reduction. Early findings during the first three years of the study had already demonstrated that lifestyle changes lowered the onset of Type 2 diabetes by 58% compared with a placebo, whereas metformin reduced it by 31%.
Compared with the original placebo group, participants in the lifestyle intervention experienced an additional three-and-a-half years without diabetes, while the metformin group gained two-and-a-half extra years. Shah highlighted, “Within three years, they had to stop the study because lifestyle was better than metformin. That means lifestyle, which everybody is banking on, is more effective—that is the news.”
Following the initial trial, the DPP was extended into the DPP Outcomes Study (DPPOS), allowing researchers to track participants’ health outcomes across decades. This long-term study provided valuable insights into how sustained lifestyle changes can prevent or delay the onset of Type 2 diabetes and improve overall health.
The findings reinforce the power of daily lifestyle choices, such as maintaining moderate weight, exercising regularly, and following a balanced diet. For those with prediabetes, this study emphasizes that consistent, healthy habits can have lifelong benefits, often surpassing what medication alone can achieve.