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The 5 Most Effective Weight Loss Diets of 2021, According to Data

'U.S. News & World Report' asked clinical experts to rank diets for their efficacy, as well as safety.

As we stare toward the end of 2021, you might feel ready for a fresh start. If this year's seen you juggle work, family, and other stress, the nearness of a new year can be the perfect inspiration to prioritize your wellness again. One of the leading consumer analysis resources, U.S. News & World Report, asked a panel of health professionals to rate which weight loss diets result in the most meaningful outcomes that are also best for your health. We've summarized their list of the best weight-loss diets of 2021, as determined by how safe, effective, and practical they are for you.

U.S. News and World Report said they asked 24 physicians, dietitians, public health specialists, and other nutrition authorities to rate 39 diets on specific criteria. The publication reports these included "short- and long-term weight loss, ease of compliance, safety and nutrition," among others. Find out their top picks, and don't miss The #1 Best Yogurt for a Healthy Gut, Say Dietitians.

Mayo Clinic Diet


The experts in this ranking liked the Mayo Clinic Diet for its approach "that makes healthy eating a lifelong habit" with a "pyramid" that reportedly promotes consuming fruits, vegetables, whole grains, and healthy fats, along with at least 30 minutes of activity per day.

(We should note that Jenny Craig received a similar score to the Mayo Clinic Diet for its weight-loss efficacy. However, some experts found the Jenny Craig was relatively pricey, while the pre-packaged meals restrict followers from typical lifestyle practices, like cooking at home for their loves ones or dining out.)

 Popular Foods You Should Avoid, According to the Mayo Clinic

Volumetrics Diet


Members of U.S. News & World Report's panel noted the Volumetrics Diet for its potential heart health and diabetes benefits. If you're curious to learn more about the volumetrics approach, we've got it right here.

Vegan Diet

healthy vegetable plant based bowl tomatoes carrots avocado brown rice cucumbers leafy greens

You've probably heard that going totally plant-based is good for your body and the planet. According to this panel of pros, the high-fiber foods and healthy fats on a well-balanced vegan diet can also show a major impact in helping you shed pounds.

The outlet also reports that currently, 6% of the U.S. population now identifies as vegan. That's up five points from just seven years ago.

 The Best Plant-Based Restaurant in Every State

WW (formerly Weight Watchers)


WW, formerly Weight Watchers, actually tied for the #1 best weight-loss diet in U.S. News & World Report's ranking. Panelists praised WW's method of allowing you to eat what you want and adopt healthy lifestyle habits.

WW's Chief Scientific Officer, Gary Foster, PhD, recently shared some thoughts with us from his new book, The Shift. Read his unique and encouraging perspective in The #1 Worst Weight Loss Mistake You Can Make, Psychology Expert Says.

RELATED: Learn more about WW's new WW PersonalPoints™ Program to help you stay on track with your weight loss goals here.



Not familiar with the flexitarian diet? This can be a great long-term lifestyle approach. U.S. News & World Report describes the flexitarian diet this way: "[…Y]ou can be a vegetarian most of the time, but still enjoy a burger or steak when the urge hits." Feeling great is all about getting your nutrients and finding balance.

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Krissy Gasbarre
Krissy is a senior news editor at Eat This, Not That!, managing morning and weekend news related to nutrition, wellness, restaurants and groceries (with a focus on beverages), and more. Read more about Krissy
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