The Mediterranean diet nudged the DASH diet out of the top spot for the best overall diet of 2019 in rankings released Jan. 2 by U.S. News and World Report. Those two approaches shared the No. 1 billing last year.
A panel of experts in diet, nutrition, obesity, food psychology, diabetes and heart disease reviewed 41 diets and rated them based on seven categories: safety, how easy they are to follow, likelihood of producing short-term and long-term weight loss, nutritional completeness and potential for managing or preventing diabetes and heart disease.
The Mediterranean diet is predicated on consuming a diet low in red meat, sugar and saturated fat and high in fish, produce, nuts and legumes. Similarly, DASH—which stands for Dietary Approaches to Stop Hypertension—prioritizes low-sodium and low-fat foods, lean proteins, fruits, vegetables and whole grains.
One important theme among the top-ranked plans, registered dietitian Lisa Drayer told CNN, is they leave room for people to indulge every once in a while.
"Whether it's a glass of red wine on the Mediterranean diet or a piece of cake on Weight Watchers, it allows people to plan for an indulgence that would otherwise be forbidden," Drayer said. "So much about weight loss is mental, and being able to incorporate all foods, including a treat, is really important for any healthy eating plan."
Trendy diets like Whole30 and keto ranked near the bottom of the list, along with other approaches that focus on high-protein or high-fat foods with minimal carbohydrates.
"Those are diets that have few substantiated claims, are extremely restrictive, harder to follow, and they eliminate entire food groups, which is really not something that's substantiated by science," Sharon Bergquist, MD, an internist who founded the lifestyle medicine and wellness programs at Emory University in Atlanta, told CNN.
The Mediterranean diet was ranked as the easiest to follow, followed by Weight Watchers and the flexitarian diet, in which users are mostly vegetarian but can have the occasional serving of meat. The Mediterranean diet won another subcategory as the best diabetes diet, with DASH and flexitarian tying for the second spot.
Weight Watchers was ranked fourth overall and No. 1 among commercial diet plans, and also rated the highest for weight loss when short-term and long-term weight loss was valued equally.