A combination of a lower-calorie Mediterranean diet, exercise and nutritional support kept overweight to severely obese people between the ages of 55 and 75 from progressing to type 2 diabetes, a new study found.
“Our study shows that modest, sustained changes in diet and lifestyle could prevent millions of cases of type 2 diabetes worldwide,” said coauthor Dr. Frank Hu, the Fredrick J. Stare Professor of Nutrition and Epidemiology and chair of the department of nutrition at Harvard T.H. Chan School of Public Health in Boston.
People who reduced their daily calories on the Mediterranean diet and engaged in moderate daily exercise — while also receiving professional weight loss support — had a 31% lower risk of developing type 2 diabetes than those who only followed the Mediterranean diet, according to the study published Monday in the journal Annals of Internal Medicine.
“I think this 31% reduction is probably a result of the combination of multiple components — improved diet quality, increased physical activity and modest weight loss,” Hu told CNN.
“The intervention group also had significant reduction in body fat percentage, and more important, a reduction in visceral adiposity (belly fat), and a significant improvement in body mass index,” he added. “The study showed that it’s not just weight loss, but also improvement in body composition may have contributed to the reduction in diabetes risk.”
At first glance, the study results were “boring,” said Christopher Gardner, Rehnborg Farquhar Professor of Medicine at Stanford University in California, who directs the Stanford Prevention Research Center’s Nutrition Studies Research Group. He was not involved in the study.
Long-term support helps adherence
The research is part of an ongoing eight-year randomized clinical trial in Spain called Predimed-Plus, in which 23 research centers tested how diet and exercise can reduce cardiovascular risk as well as other health conditions.
All 6,874 participants in the trial had body mass indexes between 27 (considered medically overweight) and 40 (considered seriously obese). While no one was diagnosed with type 2 diabetes at the start of the study, all participants had metabolic syndrome, defined as high blood pressure, high blood sugar, altered cholesterol and excess fat around the waist. Metabolic syndrome is a well-known risk factor for insulin resistance and later type 2 diabetes, as well as a buildup of plaque in arteries, which can lead to heart disease and stroke.