The Best Rapid Weight Loss Diets

Tuesday, June 6th

2023 Rapid Weight Loss Diet Reviews

Nutrisystem

• Cost: Plans start at $284.99 for 4 weeks of meals

One of the biggest reasons that diets fail is that they restrict too many things at once. "No carbs! No fruit! No grains!" No fun?! That's why we love the Nutrisystem plan for rapid weight loss: you'll continue to eat many of your favorite foods, including fruit and bread, but with a total daily calorie count that lets you shed those extra pounds.

When people use Nutrisystem, they lose an average of 11.6 pounds and 8 inches just in the first month. And, keep in mind that those numbers are just the average - you could lose significantly more, especially if you have a lot to lose. If you choose to use Nutrisystem after your initial quick weight loss, you'll probably see a consistent drop of up to 2 pounds each week, which is the threshold established by most nutritionists and physicians as a sustainable, healthy goal.

Nutrisystem offers four plans to choose from, depending on your budget and your approach to losing weight. Each plan is backed by a 14-day satisfaction guarantee. Here's what you can expect from each of the plans in the program:

• Basic: starting at $284.99 for 4 weeks, this plan includes a pre-set menu of Nutrisystem's most popular foods.
• Core: starting at $309.99 for 4 weeks, Core gives you a wider range of foods to choose from.
• Uniquely Yours: starting at $349.99 for 4 weeks, this plan gives you even more menu variety, including frozen food options.
• Uniquely Yours Plus: starting at $389.99 for 4 weeks, this gives you high-protein shakes as part of your meal and snack options.

If you need a plan designed for men, for vegetarians, or for people with diabetes, you can find links to those programs either in the scrolling bar at the top of the page or at the bottom of the site.

(Also, don't be surprised if you decide to compare Nutrisystem's offerings with South Beach. South Beach was bought by Nutrisystem several years ago, so the two sites have some similarities!)

On the Nutrisystem plan, you'll eat six times daily on the women's programs or seven on the men's (an extra snack is included). What will you eat on a typical day? Breakfast might be a cheese/turkey sausage/egg muffin, snacks like Greek yogurt/blueberries or white cheddar popcorn, cheese tortellini with a side salad for lunch, and turkey medallions with broccoli for dinner.

You may be able to save a little extra on your program purchase: just look for pop-ups as you browse the site. During our most recent visit, we got $25 off our purchase. We also spotted a promotion at the top of the page that gave us free FedEx shipping and some shakes with our order. Just be aware that when you see the pricing on the Nutrisystem site, it is based on the assumption that you'll select their automatic delivery program. You might want to select that option even if you only plan on subscribing for a month, just to get the lower price; you can cancel, update, or pause the automatic deliveries whenever you like.

If you choose one of the Nutrisystem meals that includes frozen food, don't worry: it comes packed with dry ice, so it'll still be frozen for up to 8 hours after landing on your doorstep.

In every delivery, you'll find a simple-to-follow meal plan that lets you know what to eat and when. You'll also be able to take advantage of their app, NuMi, so that your meal plan is 100% portable (no need to remember to bring the paper copy wherever you go).

Need some personal guidance as you navigate your quick weight loss journey? You'll appreciate that Nutrisystem is ready to help. Check out the Let Us Help You link on the bottom of the site; you'll get contact information for their Weight Loss Counselors, Dietary Counselors, and Program Consultants. They're on standby to offer motivation and support, specific recommendations on your meal plan or any adjustments you might need to succeed, and detailed information for any dietary restrictions due to food allergies or medical conditions.

Bottom line? Nutrisystem works. If you are trying to lose weight fast and want a plan that's convenient, easy to follow and still delicious, you'll love what they have to offer. This is our highest-rated Rapid Weight Loss Program.

Medifast

• Cost: 30-day meal kits start at $299

When you think of losing weight quickly, do you feel frustrated trying to figure out what to eat, how much, and when? If that sounds like you, Medifast could be your best choice for a Rapid Weight Loss program. It's been around since 1980 and has been the weight loss recommendation of choice by more than 20,000 doctors since then.

If convenience is a top priority, this plan definitely delivers. Medifast uses ready-made meals and snacks for most of your diet, focusing on fiber and low-fat protein to keep you satisfied while helping you shed pounds.

You have three program options with Medifast. Pay particular attention to the first one, because it's the best option if you're looking for Rapid Weight Loss:

• Medifast Go: "fast results for busy people". Each day consists of 5 prepackaged Medifast meals, plus one "lean and green" meal you prepare yourself.
• Medifast Achieve: "steady, gradual weight loss". This plan offers more flexibility, with 4 Medifast Meals, 2 "lean and green" meals and 1 healthy snack each day.
• Thrive by Medifast: this is the plan for maintaining your goal weight. This consists of 3 Medifast meals, 2 "lean and green" meals, and 1 balanced meal you create yourself.

If you're not sure which plan is the right fit for you, or if you have any particular dietary needs - vegetarian, gluten-free, nursing mother, etc. - we encourage you to call the toll-free number on the Medifast site to speak with a helpful Medifast representative.

You might be pleasantly surprised at what Medifast costs. You'll pay $329 for the Go plan, and $299 for the Achieve program. Although you'll still need to buy some groceries for your daily "lean and green" meals, your total monthly cost may not be too different from what you're already spending.

The biggest savings are offered to those who sign up for the loyalty program, Medifast Advantage. When you place an order of at least $149 and opt into the automatic delivery plan, you'll get automatic enrollment. This comes with perks like 5 to 10% back in rewards credits that can be applied to your future orders, free shipping on orders of at least $250, and $5 flat rate shipping for orders of $149 to $249.99. You can cancel the auto-ship feature at any time.

You'll also appreciate that Medifast has a 30-day satisfaction guarantee. Try their products for a month and see if you like them - or see how much weight you drop in a little over 4 weeks. (The studies referenced on the Medifast site say that the average weight loss is around 11 pounds in 8 weeks on the Go plan). You can get a full refund for any reason within those 30 days (minus shipping/handling fees).

Over the years, Medifast has proven itself as one of the best ways to achieve Rapid Weight Loss - not through fads or weird food restrictions, but rather through portion control and simplified choices. While this probably wouldn't be your choice if you're trying to learn how to eat healthy and change your habits for a lifetime, it's a fantastic, affordable choice to see the scale go down in a hurry.

South Beach

• Cost: Plans start at $289.99 for 4 weeks of meals

Who doesn't want a South Beach body? This popular diet plan averages a weight loss of around 7 pounds in two weeks, on average, and a steady drop of 1-2 pounds per week after that. The South Beach program is one of several that helps you lose weight by shifting your diet more towards protein and healthy fats and away from carbs.

The good news is that this diet program isn't as strict as many of the other low-carb plans we evaluated (like paleo, keto, etc.). When following the South Beach plan, you'll have a "budget" of 40-50 net carbs per day, depending on which phase of the program you're in.

Similar to the highest-ranked Rapid Weight Loss Diets in our review, South Beach blends the convenience of pre-packaged, carefully-portioned foods that you can buy in advance with DIY meals that you'll prepare on your own. In the beginning, though, you'll mostly be using the South Beach meals and snacks, to help you make that first big drop on the scale with high-protein foods that reduce your cravings for sugar and starch. Later in the program, you'll see fruits, whole grains and additional vegetable selections return to your range of options as you make two meals on your own each week.

There are three 4-week plans to choose from at South Beach. Each one requires you to pick the format you prefer: Chef's Pick (a preselected combination of meals/snacks) or choose-your-own-adventure. They recommend the Chef's Pick for your first 1-month program, just to keep things simple. Here's what you can expect:

• Silver: the most basic plan, which includes 4 weeks of breakfasts, lunches and dinners. This plan sells for $289.99 for women and $329.99 for men.
• Gold: this plan offers a wider menu variety, including junk-free snacks. This plan sells for $329.99 for women and $359.99 for men.
• Platinum: the most robust of the three plans, this package also includes 20 Simply Fit shakes. This plan sells for $359.99 for women and $389.99 for men.

Are you looking for a plan that's compatible for customers with Type 2 Diabetes? Be sure to check out your options under Diabetes Gold, in the Plans tab.

All of South Beach's plans include free delivery via FedEx to addresses within the lower 48 United States - just no military addresses or PO boxes, due to the perishable nature of the food in the shipments.

One small detail: the prices you see on the South Beach site assume that you're having your food automatically delivered every month. You'll pay more if you don't opt for the auto-ship setup. But, you can get discounts: browse the site long enough or go to exit the South Beach store, and you might get a pop-up offering you $50 off your order placed within 60 minutes. Also be sure to look for any promos at the top of the site; at the time of our most recent visit, we got free shakes with our purchase.

Are you wondering how the food tastes? Check out the hundreds of customer reviews on all of the entrees and snacks that appeal to you, and you'll see what real people think of each one. We were impressed with the Turkey Sausage & Egg Muffin (looks exactly the same as what you'd find at your favorite fast-food breakfast stop) and the Broccoli & Cheese Stuffed Chicken Breast (4.5 stars out of 5 over more than 800 customer ratings).

South Beach provides a program with convenience, appetizing foods, and the flexibility to choose and make some of your own meals - all while helping you lose a significant amount of weight in the first 2+ weeks. This is a solid option among Rapid Weight Loss Diets.

WonderSlim

• Cost: Plans start at $205 for 4 weeks

WonderSlim hit the market in 2001 as a high-protein, low calorie way for people to lose weight successfully. According to the company, their supplements are a medical-grade protein diet trusted by weight loss clinics, physicians, and hospitals around the country. All of their products are designed by licensed dietitians and formulated for Rapid Weight Loss while still providing essential nutrition.

WonderSlim has three plans to choose from. You can select all of the flavors yourself, or opt into the Customer Favorites (recommended for your first order):

• WonderSlim Basic Essentials: for $205 ($1.83/meal), you'll get 84 servings of meal replacement shakes or soup and 28 servings of bars/snacks
• WonderSlim Core Classic: for $243 ($1.74/meal), you'll still get 84 servings of meal replacements and 28 servings of bars/snacks, but you'll also get 28 lunches like Sloppy Joe Mix and Spicy Cheese 'n' Pasta
• WonderSlim Premium Complete: for $319 ($1.63/meal), you get everything in the Core package, plus 28 servings of breakfast

Each kit also comes with 1 Omega 3/6/9 supplement bottle, 30 WonderSlim multivitamins, 1 Lifestyle Guide, and 1 shaker bottle (for mixing all of those drink powders).

Where WonderSlim really stands out is their satisfaction guarantee. Within 60 days of purchase, you can request a refund for any reason - and not only will they give you your money back, they'll give you an extra 50% of your purchase price too, just to say thanks for giving them a try. That's impressive in the Rapid Weight Loss Diet industry. Just be aware that you can only return one partially used box or bottle of each product; unopened and unused products are always accepted for returns.

That's probably why the company has a strong reputation. At the time of our most recent review, WonderSlim's parent company (Diet Direct) had a flawless "A+" rating and accreditation with the BBB. We also appreciated all of the success stories on the site; many reviews said that people lost more than 6 pounds in the first week (though the company is very quick to say that your results may vary).

The only drawback to using WonderSlim for Rapid Weight Loss is that so much of the plan is based on meal replacement shakes. It's true that the approach will probably help you lose weight fast - but in our experience, drinking meals often leaves people feeling hungry, even when those shakes are high-protein. You'd have to try it for yourself, possibly incorporating more of the entrees with the shakes, in order to be able to stick with the program successfully.

WonderSlim is a Rapid Weight Loss Diet that has been used successfully by many customers to shed unwanted pounds quickly and without too much effort. And, if you're a big fan of shakes, you may really like this plan. Best of all, you're covered by WonderSlim's generous 150% money-back guarantee.

Atkins

• Cost: All plans and tools are FREE
• Meal kits, bars, shakes and treats available for purchase

You might say that Atkins is the original keto or paleo diet plan. In 1963, cardiologist Robert Atkins realized that his patients lost a lot of weight fast when cutting back drastically on carbs - but without the constant hunger usually seen with other diets. Since then, the Atkins approach has helped thousands of people to shed unwanted pounds and develop healthier eating habits for a lifetime.

One thing we really appreciate about the Atkins site is the variety of 100% free tools people can use on their low-carb weight loss program. From a mobile app that lets you track your food no matter where you are, to meal plans and shopping lists to take the guesswork out of what to eat, this site offers it all at no charge.

And, if you really need the control that comes by having ready-made food that lets you eat low-carb without much work (or calorie counting), the Atkins site sells a wide range of meals and snacks to simplify things. Although you'll find the Atkins line of food in some bigger supermarket chains, the easiest way to get your meals, shakes and more is by ordering through the online store. (The only exception is Atkins' frozen foods; you'll have to get those locally because they're not offered through the website.)

Whichever approach you take, you'd probably need to pick an Atkins plan to follow:

• Atkins 20 is the program that's most likely to result in Rapid Weight Loss. Designed for those who have 40 or more pounds to lose, or who are dealing with Diabetes or Prediabetes, this plan restricts your total carbs to just 20 per day. Expect to eat "foundation vegetables" (non-starchy kinds), protein, cheese, nuts, seeds, and healthy fats like avocado. Later in the program, you'll get to add in things like legumes, tomato juice, berries, melon, and Greek yogurt.
• Atkins 40 focuses on people who are trying to lose less than 40 pounds, who are pregnant or breastfeeding, or who prefer a program that starts with a broader variety of foods to choose from. Because you're probably not used to restricting your carbs to just 40 per day, this plan may also give you the quick weight drop you're looking for, but not as drastically as the Atkins 20 plan.

If you reach your goal weight and like the Atkins approach, you'd then be able to switch to the Atkins 100 plan (and yes, the 100 refers to 100 net carbs daily). Although this plan still recommends that you make the majority of your food choices from the "acceptable" list and minimize your intake of refined carbs like sugar, this plan doesn't have any food that is completely off-limits.

So, let's say you go all-in with Phase 1 of the Atkins plan. How much weight can you expect to lose? While the site gives you the standard "you can expect to lose 1-2 pounds per week" disclaimer, we found a reference by Mayo Clinic that said it's not unusual to lose up to 15 pounds in the first two weeks! But, they were quick to say that Atkins realizes that those initial losses may represent a significant amount of water weight, and that those losses aren't typical.

Still, 15 pounds in 2 weeks: weight loss doesn't get much more rapid than that! What's the downside? For a lot of people, restricting carbs so severely is extremely challenging. Think about the amount of carbs in the foods you usually eat - bananas (27g of carbs), beer (13g of carbs per can), pizza (around 36 g of carbs per slice) - and you'll start to see why a lot of people wind up binge eating and giving up on Atkins.

But, if you aren't looking for a long-term solution, just a way to shed some pounds before a big event or some other reason, Atkins can help you do it if you invest the time and self-control. You might want to experiment with some of the site's free tools before making your commitment, to see if it's a plan you can follow long enough to see the scale move.

Keto by Diet Doctor

• Cost: $9/month
• First month free with registration
• No registration needed to preview meal plan samples and videos

When it comes to losing weight with a low-carb diet, keto is one of the newest approaches in the industry. Based on the idea that if you can get your body to a state of ketosis by eating very few carbs and focusing on proteins and healthy fats, this Rapid Weight Loss Diet can be very effective. It's also the main reason why you'll see bakeries offering "keto bombs" and restaurants wrapping things in cheese instead of bread.

And, if you're looking for the most easy-to-follow way to "go keto" that has also been designed by medical doctors and other nutrition experts, Diet Doctor is one of our favorite resources. We love that this site is supported strictly by $9/month memberships, so you won't have to endure endless ads and sponsorships from companies that want to sell you something.

All of this is a result of Diet Doctor's passion for helping people around the world to get the evidence-based, unbiased information they need to make dramatic changes to their health. They're so committed to this goal that they offer a huge array of resources at no charge - and no sign-up or personal information required to access it! Want to preview 3 of their meal plans? Watch video samples explaining how they help you follow a keto diet? You'll find all of that and more. We particularly like the complete 2-week diet plan, with recipes and shopping lists: take keto for a 2-week spin and see what it does to the scale, without even having to enter your email address.

If you decide that it sounds good, you can get access for a full month - once again, at absolutely no charge. This gives you the ability to see it all: more than 100 meal plans, 700+ recipes like pesto chicken and keto pizza, "ask the expert", podcasts, and much more. You'll be able to try out anything that Diet Doctor has to offer before deciding if their extremely reasonable membership of $9 is right for you. Currently, more than 60,000 people use Diet Doctor's membership plan on their weight loss journey.

If you're not familiar with what a keto diet looks like, you can start with the video labeled "What is a keto diet?" That's the first video in a step-by-step course designed to hold your hand through all of the decisions and questions you may encounter while changing your diet to follow the keto plan.

You'll also see science-based, authoritative answers to some of the issues people raise with keto, like concerns about higher cholesterol or perceived dangers of eating too much red meat. Diet Doctor is very clear in explaining that if you are breastfeeding or on medication for high blood pressure or diabetes, you should talk with your physician before attempting such a low-carb Rapid Weight Loss Diet.

With all of these great perks, you may be wondering why keto and Diet Doctor aren't higher in our rankings. While we absolutely love what Diet Doctor has to offer, in our experience most people who are looking for a Rapid Weight Loss Program want something very controlled, easy to do, and practically guaranteed to work. Diet Doctor expects that you're going to be comfortable spending time in the grocery store and kitchen, committed to following the plan, and ready to eliminate a lot of carbs from your eating. And, because this isn't a resource that is strictly focused on quick weight loss, but rather on helping you live a low-carb lifestyle for years to come, you won't find any information about how much weight you can expect to lose while going keto. (Although it's true that a lot of people swear by the keto diet for losing weight in the short- and long-term.)

Diet Doctor makes it about as easy as a service possibly can to adapt to a keto lifestyle, with recipes that taste great and a simple-to-use interface that lets you make lots of modifications for preferences, family size, and more. But Rapid Weight Loss Program? Diet Doctor is very different from the higher-ranked diets in our review.

Noom

• Cost: Varies depending on program length
• Base price: $100 for 2 months

As a program that calls itself "the last weight loss program you'll ever need", Noom may have sparked your curiosity. Can it help you shed unwanted pounds? The answer is yes, but maybe not as quickly as you're hoping.

Don't get us wrong: we absolutely love this app and see that it's making a huge impact in the dieting industry with its psychology-based approach to people's relationships with food, exercise, stress and even sleep. In fact, when considering today's popular diets, Noom earned our highest ranking.

But, for people who are looking to make drastic changes in a short period of time, Noom may not be the best fit. When our test subject used the Noom app for almost 9 months, her initial assessment said that her target was 4 months to lose 40 pounds. Sounds great, right? Well, after following Noom for more than twice that length of time, she had lost a total of 35 pounds. That fits in very nicely with most health professionals' recommendation to lose weight at a rate of just 1-2 pounds per week - but it's certainly nothing we would call a Rapid Weight Loss Diet.

Noom is also very loosely structured in terms of what you eat. Instead of telling you a certain number of carbs you can eat each day, or what your target for protein is, the Noom app breaks foods down into green, yellow and red foods based on their nutrient density. You won't be surprised to see that fresh fruits and vegetables are typically green, while something like a chocolate milkshake is red. There's no limitation to how much of those "colors" you can eat, but they encourage you to use them as a guideline to making healthier choices.

And, if you enter any exercise - from a walk in the park to a HIIT class at the gym - you'll find your daily food budget increases by half of the calories that Noom estimates that you burned off. That's great motivation to give it a little extra in your workout or take one more lap around the block. The app also integrates with fitness trackers like iWatch and Fitbit to automatically update your steps and weight as recorded by those devices.

Noom's pricing can be a little tricky. The company no longer seems to offer a free 2-week trial. Instead, during the sign-up process, it asks you how much you think a two-week subscription is worth, ranging from $1 to $18.37 (since Noom says it costs them "just over $18 to provide each trial"). No matter what trial amount we selected, we were still given a quote of $99 for our cost after the initial 2 weeks.

However, as with most online subscriptions, you can usually finagle your way into a better deal. In our case, we opted into the trial and then held off before committing to a paid membership. After several emails with ever-lower offers, we finally purchased a 1-year membership for a little less than $150. If you're not into the waiting game, you can do a little research online and see if there are any valid discount codes at the time you'd like to subscribe.

Noom has a ton of features that make it an amazing way to lose weight....slowly, and by developing habits that will help you change for the rest of your life. Our test subject really loved working through the daily tasks in the app that kept her accountable (especially with daily weigh-ins for the first 5 months), a goal coach and a group coach who checked in to see how she was progressing, and more.

But, the reality is that if you want a silver bullet that will take care of your extra weight in a few weeks, or that will have you fitting into your Little Black Dress in time for your vacation in two weeks, Noom just isn't designed for that. You may want to consider a Rapid Weight Loss Program with lots of structure and the option to buy pre-packaged meals and snacks instead.