Your U.S. News & World Report's best diet rankings for 2018. The two diets that tied for the top spot -- the and the -- fit that bill because they feature real food and reasonable, flexible guidelines, experts said.should be based on a well-balanced eating plan that fits your lifestyle, rather than a weird fad replete with food restrictions. That's according to
"It's tasty, it's sensible, nutritionally sound, and there's great research that it can help ward off or control a whole host of chronic diseases," Angela Haupt, assistant managing editor of health at U.S. News & World Report, said of the Mediterranean Diet.
On the other hand, you should avoid fad diets that require you to adopt. The hot new Keto Diet got a raspberry from the U.S. News' panel of nutrition experts, tying for last on the list.
The Keto Diet requires people to severely restrict their carbohydrate intake while indulging in high-fat foods, a plan that is simply not sustainable, Haupt said.
"It really is the diet of the moment, but it can be a pretty extreme plan. There's a very strict carb limit. Our experts say it's not necessary to be so extreme or restrictive," Haupt said.
"One expert said if a diet recommends snacking on bacon, you can't take it seriously as a health-promoting way to eat," Haupt said.
The rankings come from an expert panel of the country's top nutritionists, dietary consultants and physicians, which evaluated 40 different diets across nine categories. The categories included ease of compliance, likelihood of short- and long-term, and effectiveness against chronic conditions like heart disease and diabetes.
Both the DASH and Mediterranean diets allow people the flexibility to choose from a wide variety of healthy foods, so they can eat what best suits them, said Kelly Hogan, clinical nutrition and wellness manager of the Mount Sinai Hospital's Dubin Breast Center in New York City.
The diets share a number of similar themes, Hogan said -- lots of colorful, whole grains, healthy fats, lean proteins, low-fat dairy, and avoidance of foods that are processed, packaged or high in saturated fats.
"The DASH and Mediterranean diets are not excluding any foods or food groups or restricting anything," Hogan said. "I think that's really important when it comes to how a normal person eats in general."
The diets also are both backed by a lot of scientific data that show they can help people lose weight and avoid heart disease and diabetes, Haupt said.
"There's a lack of good solid research on nutrition and diets in general, so it says something when a plan like the Mediterranean Diet is backed up with good solid research," Haupt said.
Fads like the Keto Diet can cause quick weight loss, but a person can't maintain such eating restrictions, Haupt and Hogan noted.
"These diets are so restrictive that of course you're going to lose weight fast because you're not eating enough calories to sustain basic activities of your body, let alone any exercise. That's nothing that any person can sustain for the long term," Hogan said. "The weight's going to come back if you do lose any weight, and then it's going to be harder to lose weight in the future."
scored high in the U.S. News rankings, coming in first as the best commercial diet and the best weight-loss diet.
"Weight Watchers offers the flexibility to shape your own diet," Haupt said. "You have to stick to guidelines about how much you're consuming every day, but what does that look like? You can eat what you want. There are no foods that are off-limits."
The plan also benefited from the amount of encouragement and accountability Weight Watchers provides its members, Haupt added.
"We know that having that support, having people to talk to and staying accountable to a plan is really important," Haupt said.
Hogan said Weight Watchers is great for people who've never really taken stock of their regular eating patterns.
"For someone who is just starting to pay more attention to what they're eating, something like a Weight Watchers can be helpful for them to start to understand things like that," Hogan said.
But she believes that people need to move on and find their own path eventually, after learning what they can from a commercial plan.
"What I don't like about any commercial diet is that the focus is not on your actual food choices," Hogan said. "It's about calories or points or numbers, and that really takes away from your ability to be in tune with your hunger cues and your fullness cues and what you're really craving. If we become more in tune with those things, we naturally consume how much the body needs. Paying too much attention to numbers takes away from that."
Dieters who want to succeed long-term need to take a hard look at themselves and what's important to them, Haupt and Hogan said.
"If you are somebody who loves restaurants, don't pick a plan that makes you toil at home over the stove," Haupt said. "If you like wine and you select a plan that completely forbids it, that makes it that much more likely that you won't be able to last on that diet."
In general, dieters ought to focus more on the positives of food rather than the negatives, Hogan concluded.
"My hope this year will be a focus on what you should eat rather than what you shouldn't eat," Hogan said. "There's no one food that most people can't eat. We should focus on what we need more of and nourish our bodies that way."