The 10 best diets for fast weight loss

Quick and dirty

Did bikini season sneak up on you? Is your soon-to-be worn wedding dress still just a touch too tight? Did a last-minute invite for a beach getaway come your way? You’re a lucky dog — and a panicked one too because you want to drop pounds, and fast. These 10 diets are likely to help you lose significant weight within a year, according to a panel of experts who reviewed 41 plans for the U.S. News Best Diets rankings. Just remember: Short-term weight loss is markedly different from long-term weight loss, which is more important for your health.

No. 1 HMR Program

The HMR Program uses meal replacements — think low-calorie shakes, meals, nutrition bars and hot cereal — in phases, coaching from experts, physical activity and an emphasis on fruits and vegetables to help dieters shed pounds fast. While last year the diet shared the No. 1 ranking in this category with the Biggest Loser diet, this year it has the top spot to itself. “This diet makes it easy to lose weight fast and would likely be effective for someone who wants to lose weight for a specific event,” one expert said. “However, as far as long-term healthy-habit-forming, this diet falls short” in part because dieters don’t learn to make their own healthy food choices.

Overall rank: 30
Overall score: 2.8 out of 5

No. 2 (tie) Atkins Diet

A large part of the appeal of the Atkins Diet, which aims to burn fat by limiting carbs and packing in fat and protein, is its claim of quick weight loss — as much as 15 pounds in two weeks, according to the company. Our experts agreed that’s a legitimate pitch, but note that much of the initial weight loss is water, due to the diet’s diuretic effect. “That means that the short-term weight loss looks much better than it really is, and when you stop the program, all the water comes back on,” one expert pointed out.

Overall rank: 37
Overall score: 2.2 out of 5

No. 2 (tie) Keto Diet

Butter, bacon, burgers, oh my! Meals consisting of high-fat foods like these are hallmarks of the keto diet, an extremely low-carb, high-fat plan that aims to send you into ketosis, a state in which your body is forced to burn fat, not sugar, for energy. Though quick weight loss is indeed likely on the keto diet, experts don’t recommend it for most people since it lacks nutritional variety and is unsustainable long term. As one expert puts it: “It is a rigid diet, it is not environmentally friendly and we don’t have epidemiological evidence of populations eating this way.” In other words: Follow at your own risk.

Overall rank: 38
Overall score: 2.1

No. 2 (tie) Optavia Diet

Optavia, a brand from the team behind Medifast, is bound to lead to weight loss in most adults. After all, you’ll likely be limited to 1,000 calories a day coming from one daily meal and five 100-calorie “Fuelings,” whether shakes, bars, eggs, oatmeal, pancakes, pudding, soup, brownies or even cheese puffs. But don’t expect to stay on this plan longer-term: One U.S. News expert called the products “unpalatable” and, on the whole, Optavia ranked less-than-optimally on metrics like safety and nutrition.

Overall rank: 31
Overall score: 2.7

No. 2 (tie) WW (Weight Watchers) Diet

WW (Weight Watchers) — a plan that uses a point system to encourage followers to choose healthy, filling foods — claims you can shed up to 2 pounds a week. Our experts back its ability to deliver quick results. Better yet? Those results are likely to last, thanks to the program’s emphasis on a balanced diet with no restrictions, as well as its built-in support system. “This is a tried-and-true plan with a proven track record, plus tools and support to help people succeed,” one expert concluded. Why not prepare for next bikini season as well?

Overall rank: 4
Overall score: 3.9 out of 5

No. 6 (tie) Biggest Loser Diet

If you’ve seen the TV show, you get the idea: Six weeks of healthy food and regular exercise is celebrated as a great start to a weight-loss journey — as well as a way to prevent or reverse various diseases. Fair enough. Experts determined that the Biggest Loser Diet is very likely to help you shed pounds, thanks to calorie restriction and exercise. But a 2016 study suggested the diet can lead to a permanent dip in metabolism, and experts also worry that the exercise guidance — as much as three hours a day — is excessive and a lot harder for average Joes than for TV stars-in-the-making.

Overall rank: 23
Overall score: 3 out of 5

No. 6 (tie) Jenny Craig Diet

Jenny Craig‘s prepackaged meals and recipes help participants lose weight — up to 2 pounds a week, it says — through restricting calories, fat and portions. One 2015 review of studies suggests it works: It found that participants lost more weight in a year on the plan than on other commercial weight-loss programs, including WW (Weight Watchers), Nutrisystem and Medifast. Experts deemed Jenny Craig “very effective” for short-term weight loss, some praising its focus on teaching proper portion sizes and helping dieters learn to eat when they’re hungry, rather than when they’re bored or emotional.

Overall rank: 11
Overall score: 3.5 out of 5

No. 6 (tie) SlimFast

SlimFast is designed to make cutting calories simple and fast weight loss likely, with products like shakes, smoothies and meal bars replacing two meals a day and snacks. “Meal replacements are supported in studies to help promote weight loss and weight maintenance,” one U.S. News expert said. But as with most diets that do well in the fast weight-loss category, SlimFast lacked in other departments, like heart health and sustainability. If you’re aiming to lose more than 20 pounds (which should take about 10 weeks on this plan), SlimFast may not be your best bet.

Overall rank: 27
Overall score: 2.9 out of 5

No. 9 (tie) Nutrisystem

Nutrisystem, a commercial plan that involves eating prepackaged and delivered meals and snacks, claims you can lose up to 13 pounds and 7 inches overall in your first month on its central plan. U.S. News experts don’t doubt it, since following the diet means restricting calories, and restricting calories leads to weight loss, at least in the short term. “Prepared foods may work for individuals who have little time to buy and prepare foods,” one expert said, “however, this aspect limits the opportunity to sustain the diet long term.”

Overall rank: 23
Overall score: 3 out of 5

No. 9 (tie) Volumetrics Diet

By filling up on bulky foods with few calories (think carrot sticks rather than cashews), as the Volumetrics Diet dictates, you’re likely to lose significant weight during the first year, experts said (1 to 2 pounds per week to be exact, according to the company). The plan is praised for teaching dieters portion control and how to choose foods that are low in calories but keep you feeling fuller longer. It’s also a “different and effective approach that is uncomplicated and flexible — what most people need to stay with any eating plan,” one pro said.

Overall rank: 6
Overall score: 3.8 out of 5

Best Fast Weight-Loss Diets

— HMR Program

— Atkins Diet

— Keto Diet

— Optavia Diet

— WW (Weight Watchers) Diet

— Biggest Loser Diet

— Jenny Craig Diet

— SlimFast

— Nutrisystem

— Volumetrics Diet