For the fifth year in a row, the Mediterranean diet has been named best overall diet by U.S. News & World Report. The DASH diet and flexitarian diets came in a close second and third, respectively.

A team of 27 experts assessed 40 diets and graded them based on numerous criteria, including how easy they are to follow and if they are beneficial in reducing cardiovascular disease or diabetes.

According to a new analysis, the Mediterranean diet is the most beneficial for heart health. Numerous studies have also found it beneficial to lower the risk of diabetes, high cholesterol, dementia, memory loss, depression, and breast cancer.

The diet is less of a restricted diet and more of a lifestyle cuisine: It consists of plant-based meals, healthy grains, legumes and seeds, nuts, with a large emphasis on olive oil. 

Other fats, like butter, are rarely if ever used, while most sugar consumption is reserved for special occasions.

Red meat is used in moderation, generally solely to season a meal. Eating omega-3-rich fish is recommended, whereas eggs, dairy, and chicken are consumed in considerably lesser quantities than in the standard Western diet.

Social connections at meals, as well as physical activity, are fundamental tenets of the Mediterranean diet. Consuming with friends and family, conversing over meals, consciously eating favorite foods, and mindful movement and exercise are all part of the diet.

Flexitarian 

The Mediterranean diet won first place in best diet for diabetes, tied with flexitarian and vegan diets.

The Flexitarian diet mixes the terms "flexible" with "vegetarian." Some meat products are consumed with mostly plants.

The vegan diet, however, excludes all animal products, including dairy and eggs.

Weight loss

Diets that were most useful for weight loss were tied with the WW (formerly Weight Watchers) and Volumetrics, along with the flexitarian diet.

The famous Weight Watchers diet plan includes an essential component of any successful diet: social support. The Volumetrics diet focuses on reducing the energy density (calories) of the meals you consume.

Last in line

The Dukan Diet was ranked at the bottom of the list of best diets. Other bad performances were Whole30, which tied for 35th rank, and the popular keto diet, which tied for 37th place with the modified keto diet.

Experts often regard the Dukan, Whole30, and keto diets, which stress eating high-protein or high-fat meals with minimum carbs, as bad because they are exceedingly restricted, difficult to follow and remove whole food groups, which is not advised by dietary standards.