Methodology

For this year's rankings, U.S. News partnered with The Harris Poll and a panel of 69 experts, including medical doctors, registered dietitian nutritionists, nutritional epidemiologists, chefs, and leading weight-loss researchers to evaluate 38 diets across 21 categories.

When rating the best overall diets, panelists considered four criteria:

• Nutritional completeness
• Health risks and benefits
• Long-term sustainability
• Evidence-based effectiveness

This year, U.S. News shifted away from ranking diets to rating them instead. This updated evaluation system "reflects the diverse needs and goals of individuals" and considers "factors beyond weight loss," according to Gretel Schueller, managing editor of health at U.S. News. "By moving away from a ranked list of diets and nearly doubling our number of evaluated health and lifestyle categories, U.S. News aims to provide consumers with a more personalized experience as they consider their health priorities and eating goals."

U.S. News added 12 new Best Diets categories for evaluation this year, including:

• Best Diets for Arthritis
• Best Diets for Brain Health & Cognition
• Best Diets for Diverticulitis
• Best Diets for Fatty Liver
• Best Diets for Gut Health
• Best Diets for High Blood Pressure
• Best Diets for High Cholesterol
• Best Diets for IBS
• Best Diets for Inflammation
• Best Diets for Menopause
• Best Diets for Mental Health
• Best Diets for Prediabetes

This year's list also includes 13 newly evaluated diets:

• Acid Reflux Diet
• AIP Diet
• Alkaline Diet
• Body Reset Diet
• BRAT Diet
• Cleveland Clinic Diet
•  GAPS Diet
• Gluten-Free Diet
• Gout Diet
• Low FODMAP Diet
• Low-Residue Diet
• Menopause Diet
• Whole30 Diet

When considering the 20 categories based on general lifestyle goals or on managing, preventing, or treating specific health conditions, U.S. News asked panelists to pick the diets they would most recommend for each goal or condition.

The percentage of recommendations were then expressed in a decimal range between zero and one before being multiplied by five to reach a scale between zero and five. For example, if a diet received 54.69% of recommendations, its score would be 0.5469 multiplied by five, which would be a rating of 2.7.

Meanwhile, the top diets in other categories were:

• The Mediterranean diet, which was the highest-rated diet for diabetes, gut health, and mental health
• The Low-FODMAP diet, which was the highest-rated diet for IBS
• The Menopause diet, which was the highest-rated diet for menopause
• WeightWatchers, which was the highest-rated diet for weight loss
• The Jenny Craig diet, which was the highest-rated diet for fast weight loss
• The DASH diet, which was the highest-rated diet among best heart-healthy diets