Mediterranean Diet Combined With Lifestyle Changes May Lower Diabetes Risk By 31 Percent: Study Shows - Video

A Mediterranean-style diet, when paired with calorie restriction, moderate physical activity, and professional weight loss support, can reduce the risk of type 2 diabetes (T2D) by 31%, according to a new study set to be published on August 25, 2025, in the Annals of Internal Medicine. The findings come from the PREDIMED-Plus clinical trial—the largest nutrition and lifestyle trial ever conducted in Europe—and were co-authored by researchers from 23 Spanish universities and the Harvard T.H. Chan School of Public Health.

The study focused on understanding whether additional healthy lifestyle changes could amplify the benefits of the Mediterranean diet, which is already associated with a lower risk of T2D due to improved insulin sensitivity and reduced inflammation

In the trial, 4,746 participants aged 55 to 75, all overweight or obese and diagnosed with metabolic syndrome but free from T2D at the start, were randomly assigned to two groups. The intervention group followed a calorie-restricted Mediterranean diet, cutting about 600 calories daily, engaged in regular moderate physical activity—including brisk walking and strength exercises—and received professional guidance on weight management. The control group adhered to the Mediterranean diet without any restrictions, exercise plans, or additional support.

After six years, the intervention group showed a 31% lower incidence of type 2 diabetes compared to the control group. They also achieved greater weight loss, averaging 3.3 kilograms versus 0.6 kilograms in the control group, and saw a larger reduction in waist circumference—3.6 centimeters compared to just 0.3 centimeters.

“We’re facing a global epidemic of diabetes,” said co-author Frank Hu, Chair of the Department of Nutrition at Harvard Chan School. “With the highest-level evidence, our study shows that modest, sustained changes in diet and lifestyle could prevent millions of cases of this disease worldwide.”

“In practical terms, adding calorie control and physical activity to the Mediterranean diet prevented around three out of every 100 people from developing diabetes—a clear, measurable benefit for public health,” added co-author Miguel Martínez-González of the University of Navarra.

The results highlight the potential of comprehensive lifestyle interventions in preventing chronic disease and underscore the importance of combining dietary approaches with behavioral support for long-term impact.

Reference: Miguel Ruiz-Canela, Dolores Corella, Miguel Ángel Martínez-González, et al. Comparison of an Energy-Reduced Mediterranean Diet and Physical Activity Versus an Ad Libitum Mediterranean Diet in the Prevention of Type 2 Diabetes: A Secondary Analysis of a Randomized Controlled Trial. Ann Intern Med. [Epub 26 August 2025]. doi:10.7326/ANNALS-25-00388