I did not know this, but U.S. News and World Report ranks not just colleges and hospitals; apparently, it ranks diets, too. Maybe this is new; I don’t know.
They rated diets in an overall category (DASH diet won here), as well as for weight loss, heart health, and diabetes.
Recent research has suggested that no particular diet is really superior to another, which makes sense. What matters most is overall eating healthier and being physically active, and most of the diets result in healthier eating. Fad diets that heavily emphasize one thing (carbs, no carbs, fats, no fats, etc.) are just that: fads. From the actual medical research I have seen, I completely agree with their top diets: DASH, TLC, Mayo Clinic, Mediterranean, and Weight Watchers.