Which diets are healthiest in national U.S. News study? And which ones fail?

As folks ponder New Year’s resolutions around eating better or losing weight, U.S. News & World Report issued its 14th annual Best Diets rankings Wednesday. And no surprise to those who’ve been paying attention to the health benefits of different food approaches, the Mediterranean diet is — for the seventh year — the best diet overall.

The honor derives from a variety of factors, according to Shanley Chien, senior editor of health. She told Deseret News that the Mediterranean diet favors healthy eating in a balanced way, with lots of fruits and vegetables, whole grains, legumes, nuts, herbs and spices, and healthy oils. It’s flexible and sustainable, she said, focusing on types of food rather than being prescriptive, and can even be translated into different cultures, such as an Asian equivalent or a Costa Rican one that uses those areas’ local foods.

The Mediterranean diet took top honors in several categories, including best diet for diabetes, best heart-healthy diet, easiest diet to follow, best diet for bone and joint health, best family-friendly diet and best diet for healthy eating.

In the best diet overall category, the DASH diet came in second and the MIND diet came in third.

Those two have similarities to the Mediterranean diet, but the DASH diet — it stands for dietary approaches to stop hypertension — was constructed to directly counter high blood pressure and is somewhat more restrictive in that it limits the amount of sodium and saturated fats, for instance, while the Mediterranean diet focuses on what to eat, not how much. The MIND diet combines elements of the other two and emphasizes foods known to be brain-health-friendly. The acronym stands for Mediterranean intervention for neurodegenerative delay.

Dementia is the No. 6 killer in the U.S., so the MIND diet promotes brain health with foods rich in omega-3 fatty acids, nuts, berries and dark green leafy vegetables, offering advice on increasing how much of those one consumes, Chien said.

“I think when people are looking into the new year to improve their health, whether they’re looking to lose weight, which is always a popular one, or they’re looking to manage health conditions like high blood pressure or diabetes, there are a lot of diets and eating approaches out there,” she said.

Because of its comprehensive approach and design, Chien said that the U.S. News best-diets ranking “cuts through all of that diet chatter to help readers make informed decisions about their next step in their health journey.” She called the diets that ranked highest easy to sustain and easy to follow — “flexible and accommodating.”

Rating 30 diets

This year’s analysis includes 30 different diets, including six that are new: the Dukan diet, HerbaLife Nutrition, HMR Program, Profile Plan, Plantstrong and the vegan diet. The vegan diet “cracked the top 10 in all categories except for best diet programs,” U.S. News said in a release.

That was no surprise to Chien, who said that while she couldn’t speak for the experts who analyzed all the diets to arrive at the rankings, “I think that the key takeaway here is that the more researchers and scientists are learning about a plant-based diet, the more we’re realizing it has such a huge benefit on our health in more ways than we realize,” Chien said.

U.S. News and the Harris Poll collaborated on the ranking system, using evaluations by 43 experts — a slate of panelists that included medical doctors, registered dietitian nutritionists, nutritional epidemiologists and academic weight-loss researchers, among others.

The ranking methodology considered not only what food groups were included in a diet, but what was left out, whether foods were nutrient-rich, if they needed supplementation to be healthy, if they’re sustainable, whether the required foods are easy to obtain, if a diet could be modified to meet cultural, religious or personal preferences and other factors, including whether a diet was suitable for the whole family. The experts also looked at nutritional adequacy and the impact of a diet on different health conditions. Then U.S. News interviewed nutrition experts as it reported out the diets and the findings.

The package includes a disclaimer, noting that those choosing a diet should talk to a medical professional “as part of their decision-making process.”

Low scores for quick fixes

What the low-rated diets have in common is inflexibility and being hard to sustain, said Chien. “I think when you look at the bottom five diets — the Atkins diet, SlimFast, Dukan, Herbalife Nutrition and the Raw Food diet — they’re overly restrictive in nature,” she said, noting they tend to rely on processed foods and supplements. Unlike the higher-rated diets, they exclude some whole foods or food groups, said Chien and typically provide a quick-fix for weight loss rather than something that can become a healthy way of life.

“Nobody wants to eat or follow a highly restrictive diet for years on end. It’s one of those things where you start it, get results and you’re done,” she said.

“The truth is, dieting is hard. Many fad diets don’t work. But a lot of people will gravitate toward them because they’re trending on social media or they hear about it,” Chien said.

As for the rankings, the diets were rated in 11 categories. Each is also explained in some detail. Among the ratings:

Best Weight-Loss Diets: 1. WeightWatchers diet. 2. Mediterranean diet. 3. Volumetrics diet.

Best Diet Programs: 1. Weight Watchers diet. 2. Mayo Clinic diet. 3. Noom diet.

Best Fast Weight-loss Diets: 1. Keto diet. 2. Atkins diet. 3. Nutrisystem diet.

Best Family-Friendly Diets: 1. Mediterranean diet. 2. Flexitarian diet. 3. DASH diet.

Best Diabetes Diets: 1. Mediterranean diet. 2. DASH diet. 3. Flexitarian diet.

Best Heart-Healthy Diets: 1. Mediterranean diet. 2. DASH diet. 3. Ornish diet.

Best Diets for Bone and Joint Health: 1. Mediterranean diet. 2. DASH diet. 3. Flexitarian diet.

Best Plant-Based Diets: 1. Flexitarian diet. 2. Mediterranean diet. 3. Vegan diet.

Best Diets for Healthy Eating: 1. Mediterranean diet. 2. Flexitarian diet. 3. DASH diet.

Easiest Diets to Follow: 1. Mediterranean diet. 2. Flexitarian diet. 3. DASH diet.

The full list and an explanation of the entire process and findings are available online here.