Aug 22: Researchers from the University of North Carolina at Chapel Hill and collaborating institutions have shown that a Mediterranean-style eating pattern adapted for people living in the Southeast can improve diet quality and support weight loss.
The study, called DELISH (Delicious Eating for Life in Southern Homes), evaluated a “Med-South” dietary pattern that emphasizes nuts, vegetables oils, whole grains, non-starchy vegetables, and fruit and is tailored to regional food preferences and availability. Results from the trial are published in JAMA Network Open.
Study leadership and design
The research team was led by co-principal investigators Thomas Keyserling, MD, MPH, professor of medicine in the Division of General Medicine and Clinical Epidemiology at the UNC School of Medicine, and Carmen Samuel-Hodge, PhD, RD, research professor in the Department of Nutrition at the UNC Gillings School of Global Public Health and director of the Evaluation Core for the UNC Center for Health Promotion and Disease Prevention. HPDP, where both Keyserling and Samuel-Hodge are fellows, served as the administrative home for the study.
Researchers developed the Med-South Weight Loss Program to align with a Mediterranean-style dietary pattern while adapting it to foods commonly eaten in the Southeast. The goal was to test whether this approach could produce sustained weight loss and improve diet quality compared with a more traditional calorie-focused intervention.
The study enrolled 360 adults with a body mass index of 30 or higher from primary care practices in central North Carolina. Participants were randomly assigned to one of two interventions: the Med-South Weight Loss Program or a control weight loss program focused primarily on reducing caloric intake.
Over 24 months, Med-South participants took part in three phases:
Phase 1: Improve diet quality.
Phase 2: Focus on weight loss while maintaining the Med-South eating pattern.
Phase 3: Maintain weight loss.
Researchers collected data on body weight, diet quality, blood pressure and other measures at four, 12 and 24 months. Diet quality was assessed using food intake questionnaires and the Veggie Meter, a device that measures carotenoid levels in the skin. Carotenoids are compounds found in many fruits and vegetables, and skin levels correlate with fruit and vegetable intake.
Key findings
“Incorporating a healthful dietary pattern into lifestyle weight loss programs should be a priority,” Keyserling said. “While similar weight loss can be achieved with calorie-restricted diets, there are added benefits to chronic disease prevention associated with a healthful dietary pattern.”
The authors note that people living in the Southeast experience higher rates of chronic diseases such as diabetes, cardiovascular disease and stroke. Lifestyle factors, including poor dietary patterns, play a major role in these conditions. Prior research has shown that eating patterns that prioritize high-quality fats (such as nuts, seeds and vegetable oils) and high-quality carbohydrates (such as whole grains, fruits and vegetables) can lower cardiovascular disease risk more effectively than conventional low-fat weight loss diets.