The Best and Worst Diets For 2020, Ranked by Nutritionists

The Keto Diet didn’t do so well.

Mediterranean Diet Promo
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A lot of people wake up on January 2nd—after a holiday season full of parties, vegetating in front of screens and eating wonderfully terrible-for-you food—and realize they need to drop a few pounds. That’s when gyms briefly fill up again and everyone hits Google to search out some kind of dietary solution that won’t cause them to lose their minds along with a few inches from their waistlines. 

U.S. News & World Report (USNWR) is here to help narrow down that search for a solution with their ranking of the “Best Diets Overall” for 2020. Despite the great Google search rankings for some common diets you’ve surely already heard of—namely the keto diet—USNWR has some surprises in store.

(Photo: Getty)

U.S. News explains how they determined their diet rankings:

A panel of nationally recognized experts in diet, nutrition, obesity, food psychology, diabetes and heart disease reviewed our profiles, added their own fact-finding and rated each diet in seven categories: how easy it is to follow, its ability to produce short-term and long-term weight loss, its nutritional completeness, its safety and its potential for preventing and managing diabetes and heart disease.

We also asked the panelists to let us know about aspects of each diet they particularly liked or disliked and to weigh in with tidbits of advice that someone considering a particular diet should know.

After every diet received robust scrutiny, we converted the experts’ ratings to scores and stars from 5 (highest) to 1 (lowest). We then used those scores to construct nine sets of Best Diets rankings…

No big surprise here: the Mediterranean Diet took top honors again. The diet that was tops last year and has been proven to help reduce the worst form of belly fat is still number one because, according to experts, it has “host of health benefits, including weight loss, heart and brain health, cancer prevention, and diabetes prevention and control.”

It’s also got the distinct advantage of not being all that specific—after all, the Mediterranean countries (Greece, Italy) that rely on it for their improved rates of health and longevity each have their own versions. Those just follow some common principles and are “low in red meat, sugar and saturated fat and high in produce, nuts and other healthful foods,” according to USNWR.

Keto-friendly snack plate

The keto diet, however, which has perhaps some of the best word of mouth, didn’t fare well in this ranking at all. It’s number 34 out of 35. According to the magazine’s editors, Keto merited a 3 out of 5 score for aiding weight loss, but just a 1.8 out of 5 for being healthy.

The implication being yeah, a diet high in fats and proteins with no carbs to speak of will definitely kick your body into a fat-burning state, but the jury is out as to just how good that might be for anyone’s long-term health. 

Paleo didn’t fare much better. The diet that is, in U.S. News terms, “based on a simple premise – if the cavemen didn’t eat it, you shouldn’t either,” was number 29 out of 35. The experts scored it as mediocre, basically, ranking it a 2.6 out of 5 in the “healthy” and “weight loss” categories. 

Here’s the full list with links to U.S. News and World Report breakdowns—note that there are plans tied for the same position—diets that are equally ranked—so USNWR left some numbers out to account for that:

1. Mediterranean Diet

2. DASH Diet tied with The Flexitarian Diet

4. WW (Weight Watchers) Diet

5. Mayo Clinic Diet tied with MIND Diet and Volumetrics Diet

8. TLC Diet

9. Nordic Diet tied with Ornish Diet and Vegetarian Diet

12. The Fertility Diet tied with Jenny Craig Diet

14. Asian Diet

15. Dr. Weil’s Anti-Inflammatory Diet tied with Nutritarian Diet

17. Vegan Diet

18. The Engine 2 Diet tied with South Beach Diet

20. Biggest Loser Diet tied with Glycemic-Index Diet, Nutrisystem Diet, and the Zone Diet

24. Macrobiotic Diet tied with SlimFast Diet

26. HMR Program

27. Optavia Diet

28. Alkaline Diet

29. The Fast Diet tied with Paleo Diet

31. Raw Food Diet

32. Atkins Diet

33. Whole30 Diet

34. Keto Diet

35. Dukan Diet

Noting that the Atkins Diet—a venerable plan that’s been in use for years and like Keto focuses on a high-protein, high fat program—was ranked at 32, an Atkins rep emailed a statement to Maxim in which they said these yearly diet rankings “rely on antiquated research by using the U.S. Dietary Guidelines” as the baseline for evaluation.

Atkins says those guidelines “are outdated and do not reflect current science,” and that there are today “more than 100 clinical, peer-reviewed independent studies that demonstrate the efficacy and safety of a low-carbohydrate lifestyle.”

According to Atkins, there is “ample research that shows that by controlling carbohydrates, people can improve health markers pertaining to weight loss, cardiovascular disease and metabolic syndrome.” 

“It is time,” they concluded, that “U.S. News & World Report stop relying on the dogma of the past and start using the science of today.”

Whatever you choose, the main thing that matters is sticking with it—so don’t pick something that you’ll hate.