Mediterranean-style diet matches Weight Watchers in weight loss efficacy

A two-year randomized clinical trial, known as the DELISH study, has found that a Mediterranean-style dietary intervention produces weight loss results comparable to the commercial program Weight Watchers (WW).

The study, published in JAMA Network Open, compared the Med-South program—a Southern adaptation of the Mediterranean diet—with Weight Watchers. While both programs achieved similar weight loss among adults with obesity, the Med-South approach resulted in significantly greater improvements in overall diet quality.

The Med-South program emphasizes the consumption of fruits, vegetables, beans, whole grains, nuts, seeds, fish, and vegetable oils while reducing refined grains and sugar-sweetened beverages. Unlike the digital tracking and workshop model used by Weight Watchers, Med-South focuses on gradual, sustainable changes to eating patterns designed to fit regional food preferences in the southeastern United States.