BlogWeight LossBest Weight Loss Diets 2021 (by Unimeal Experts)

Best Weight Loss Diets 2021 (by Unimeal Experts)

Mariia Roza
Written by Mariia Roza on November 24, 2021
Medically reviewed by Dr. Olena Avdiievska

Table of contents

If you want your New Year’s resolutions to work and get into the best shape of your life in 2022, now is the high time to choose the proper weight-loss strategy. 

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In this article, we’ve gathered 13 diets we were writing about during this year. We’ve evaluated their efficacy for weight loss and gave a summary of their health benefits. Checked if these diets have any scientific backup and analyzed their affordability. We also figured out how restrictive they are and presumed how sustainable the weight loss results would be after the diet.

The main principle of all diets

What’s important to remember about weight loss diets is their main principle. The only way how they help you to burn fat is by creating a calorie deficit.

Do you feel like it’s easier for you to create a calorie deficit by narrowing your eating windows? Then choose intermittent fasting protocols which will make you skip breakfast, dinner, or even days of eating.

Do you want to cut off some food groups from your diet to eat fewer calories? Then opt for highly restrictive diets like the ketogenic, vegan, or pegan diet.

However, remember that the weight loss happens only because of a calorie deficit you create. There’s no scientifically backed up reason to choose them over a standard low-calorie diet. If additional restrictions help you stay in a calorie deficit – enjoy your diet. If they make your dieting harder, opt for more sustainable and less restrictive eating systems.

Weight loss and weight maintenance

Remember that the more limitations during the weight-loss period you have, the harder it will be to maintain your new weight. If you think about it a bit harder, you will understand that your New Year’s wish should be not to lose weight but to be in good shape for the rest of your life.

Losing weight is only half of the journey. Another part of it is sustaining your new physique. And the slower you go losing weight, the more sustainable your results will be.

Diets for health

Losing weight is not only about looking better. For a lot of us, it’s also about being healthier. Fortunately, some diets can help you lose weight and improve your overall health. We’ve added a bonus point to the overall score of the diets which can make you both thinner and healthier.

Not all diets will decrease your health risk factors. Moreover, some of them might even be harmful to your health without proper medical supervision. We’ve added a warning note to such diets: Please, don’t neglect it.

Now, when all the disclaimers and explanations are made, let’s get to the point! Here are our top-13 diets for health, weight loss, and weight maintenance.

The Mediterranean diet

The tastiest diet for health and weight loss. It incorporates eating habits from the countries around the Mediterranean sea. It offers eating fruits and vegetables for vitamins and minerals; seafood, fish, and lentils as main protein sources; and nuts, olive oil, and avocado as main sources of healthy fats.

Opt for whole foods, minimize the amount of overly processed products, and keep an eye on your portion sizes to lose weight.

Requires medical supervisionNo need in medical supervision
Overall health benefits

The Mediterranean diet is proven to be one of the healthiest diets in the world. It improves heart condition, normalizes blood sugar and cholesterol levels.

+1 bonus

Scientific researchThe Mediterranean diet's efficiency in decreasing health risk factors and improving overall health is backed up by cohort studies that took over 50 years of research.
Weight loss speed

5/10

The speed of your weight loss highly depends on the number of calories you eat. If you want to lose weight on a Mediterranean diet without counting calories, you will have to control your portion sizes, choose fruits for dessert, and stay physically active.

Affordability

7/10

If you don’t live near the Mediterranean sea, this diet might be more expensive than an average low-calorie diet.

Restrictiveness (how easy it is to follow)

8/10

On the one hand, you don’t have severe restrictions on this diet. On the other hand, as you will have to cook more, following the Mediterranean diet might be more time-consuming.

Weight maintenance and sustainability for life

10/10

The Mediterranean diet is highly sustainable for life. Moreover, it teaches you how to choose high-quality products and mind your portion sizes. This knowledge will help you maintain your new physique after the weight loss.

Overall score:8.5 out of 10

The DASH diet 

DASH is an acronym for Dietary Approaches to Stop Hypertension. It helps decrease high blood pressure by limiting salt and overly processed foods consumption. The DASH diet prescribes eating a lot of grains, fruits, and vegetables, a decent amount of fat-free dairy products, and up to 200 grams (5-6 ounces) of lean protein a day. 

Requires medical supervisionNo, however medical advice is preferable in case of severe health conditions.
Overall health benefits

The DASH diet is an efficient way to help treat high blood pressure. As it presumes that you eat a more balanced and varied diet, other health improvements are highly possible.

+1 bonus

Scientific researchThe diet is well researched and is proven to improve health. Its efficiency for weight loss is also backed up by science.
Weight loss speed

6/10

As the DASH diet describes both the quantity and the quality of food you should be eating, it is helpful for weight loss. However, that’s not going to be a fast weight loss.

Affordability

8/10

The DASH diet is variable and might require more shopping and more expenditures on food.

Restrictiveness (how easy it is to follow)

8/10

The DASH diet is quite easy to follow.

Weight maintenance and sustainability for life

8/10

The DASH diet is not highly restrictive and hence, can be sustained for life. It teaches you how much to eat and what food to choose, so it can be quite efficient in weight maintenance. It also has two phases, the second one being less restrictive and more convenient for weight maintenance.

Overall score:8.5 out of 10

Intuitive eating

It is a relatively new approach to weight management. This “diet” should not be the first choice for individuals who cannot see the difference between emotional and physical hunger. Try this approach if you already have some basic understanding of nutrition and can listen to your body. 

Requires medical supervisionNo need for medical supervision
Overall health benefits

Intuitive eating principles are used to treat individuals with eating disorders. What’s more, they help build healthy relations with food.

+ 1 bonus

Scientific researchThere is not much research on intuitive eating as all its benefits or downfalls are very subjective. The case studies at hand cannot be used as a reliable scientific backup.
Weight loss speed

1/10

Intuitive eating is not recommended to overweight or obese individuals who need to lose weight for health reasons. This is because its main principle is about refraining from dieting and restrictions. Losing weight is not the main goal of intuitive eating. Hence, seeing weight loss results when eating intuitively might take some time.

Affordability9/10
Restrictiveness (how easy it is to follow)

8/10

On the one hand, intuitive eating is all about refraining from restrictions. On the other hand, it’s not that easy to follow it, if you haven’t listened to your body for the most part of your life!

Weight maintenance and sustainability for life9/10
Overall score:7.75 out of 10

Low-calorie diets

When we’re referring to the low-calorie diet, we’re talking about creating a 300 to 500 calorie deficit per day. This diet has the largest pool of scientific research and is proven to be effective for weight loss.

Among the main downfalls of low-calorie diets is the necessity to count calories. Another difficulty of this approach is that if dieters don’t change the quality of food they consume and come back to random eating habits after the diet, weight maintenance becomes quite challenging.

Requires medical supervisionNo need for medical supervision
Overall health benefitsImproves health as far as you get closer to your normal BMI and pay attention to the quality of your food and not only its quantity.
Scientific researchLow-calorie diets are well-researched. They are proven to help you lose weight.
Weight loss speed

8/10

You will lose half to one pound of weight per week.

Affordability

8/10

It can be the same food you’re eating, just in smaller quantities. However, if you’re dieting the smart way, you will switch high-calorie foods for their low-calorie alternatives. Funny as it may seem, low-calorie foods are often a bit more expensive than their original versions. 

Restrictiveness (how easy it is to follow)

6/10

The sustainability of this diet depends on the calorie deficit you choose. The larger the calorie deficit is, the harder it is to follow such a diet. By creating a slight 300 calorie deficit, you will make your diet more bearable. By increasing your deficit, you will make dieting more challenging.

Weight maintenance and sustainability for life

6/10

Most people who follow low-calorie diets without changing the quality of their food or their eating habits, regain their weight back. However, if you opt for a small calorie deficit and change the quality of food you eat, your chances to maintain a new weight increase.

Overall score:7 out of 10

Low-carb diets

Much less restrictive than the ketogenic diet, low-carb diets allow you to eat under 150 grams of carbs a day. They limit the consumption of sugar, bread, grains, pasta, starchy vegetables, and some fruits. Low-carb diets use vegetables with a low glycemic index as the main source of carbohydrates and fiber.

Requires medical supervisionNo, however medical advice is preferable. There are some health conditions when a low-carb diet is not recommended.
Overall health benefitsIt might have some positive effects on insulin and cholesterin levels and help treat heart conditions and type 2 diabetes.
Scientific researchAs well as the ketogenic diet, the low-carb diet is proven to be efficient for weight loss.
Weight loss speed

9/10

More than one pound a week weight loss is possible. You lose weight faster when you cut off carbs, as carbs retain liquid. When you don’t eat carbs, you face fast water loss.

Affordability

7/10

Protein and fat sources are usually more expensive than sources of carbohydrates. Low-carb highly-processed products are also more expensive than traditional snacks.

Restrictiveness (how easy it is to follow)

6/10

Overall, this diet is quite sustainable as you can choose to eat from 0 to 150 grams of carbs per day. 

Weight maintenance and sustainability for life

6/10

You learn a lot about food quality and can change protein and fat ratios in your diet. So, this diet is more sustainable in the long run than the keto diet. However, if you stop following the low-carb diet, you might regain some of the weight back quite rapidly.

Overall score:7 out of 10

OMAD (One Meal a Day)

Eating only once a day can be a blessing for some people, helping them to decrease their calorie intake as they skip meals and refrain from snacks. For others, intermittent fasting protocols can become a curse, leading to eating disorders and binge episodes. 

Requires medical supervisionNo, however medical advice is preferable. There are some health conditions when prolonged fasting periods are not recommended.
Overall health benefitsOMAD might have the same health benefits as other intermittent fasting protocols, like decreasing risks of type 2 diabetes and improving brain functions.
Scientific researchMore research should be conducted on the OMAD to provide reliable data on the topic.
Weight loss speed

7/10

The weight loss speed depends on the number of calories you consume during your meal. If you follow diet recommendations (like eating high-fiber whole foods and minimizing processed products), you won’t be able to consume too many calories in one sitting and will lose weight faster.

Affordability

9/10

This diet doesn’t force you to count calories or change the types of food you’re consuming. It’s as affordable as your normal eating.

Restrictiveness (how easy it is to follow)

6/10

Fasting for almost 23 hours a day can be pretty challenging.

Weight maintenance and sustainability for life

6/10

Some individuals state that they follow OMAD for years. However, this weight management approach is not sustainable for most people.

Overall score:7 out of 10

Dr. Nowzaradan’s diet

This high-protein, low-carb, low-fat diet was developed by the bypass and gastric sleeve surgeon, Dr. Younan Nowzaradan. It is based on lean protein sources and vegetables, doesn’t allow dieters to have snacks, and contains only 1,200 calories. 

This diet is not for everyone and should be prescribed by a health provider. 

Requires medical supervision

Yes

The traditional Dr. Now diet is only 1,200 calories, this number is too low and the medical consultation is highly advised.

Overall health benefitsImprove health as far as you get closer to your normal BMI and reduce the health risks you had due to being obese or overweight.
Scientific researchThere is a strong scientific explanation why this kind of dieting is prescribed to patients who’re going to have weight loss surgery.
Weight loss speed

9/10

If you follow a 1,200 or 1,000 calorie diet, you can lose more than two pounds a week. Dr. Now’s morbidly obese patients (from My 600-lb Life TV show) were losing about 20 pounds a month. 

Affordability

9/10

There’s no need for lobsters, caviar, or exotic fruits. You just opt for whole foods and eat much less.

Restrictiveness (how easy it is to follow)

5/10

1,200 calories are very little. If you follow this diet for a prolonged period of time, you will feel a lack of energy, you will always be cold, and your cravings will increase. This kind of dieting is hard to sustain for long. 

Weight maintenance and sustainability for life

4/10

If you’re not about to get a weight-loss surgery (like Dr. Now’s patients), you don’t have many chances of sustaining your weight loss. However, if you eat more calories and follow the main principles of Dr. Now’s diet, you get more chances of maintaining your new physique.

Overall score:6.75 out of 10

3-day fasting

Fasting is a very efficient way to lose weight, as during fasting your body has to utilize fat tissue as fuel. However, during prolonged periods without food, including the 72-hour fasting, dieters should stay under medical supervision.

Requires medical supervision

Yes

72-hour fasting is considered a prolonged period without food, so medical supervision is highly recommended.

Overall health benefitsMight improve blood sugar and blood pressure. On the other hand, prolonged fasting can cause nutrient deficiency and the start of yo-yo dieting cycles. 
Scientific research72-hour fasting is well researched. It should not cause health problems when you’re under medical supervision.
Weight loss speed

10/10

An individual can lose up to six pounds in three days. The number of pounds lost depends on the initial body weight.

Affordability

10/10

You need nothing but water, and, in some cases, salt and electrolytes. 

Restrictiveness (how easy it is to follow)

3/10

People who fast regularly state that after a certain period, you don’t feel hunger urges. However, your first days without food will be quite challenging.

Weight maintenance and sustainability for life

3/10

Prolonged fasting might cause disruptive eating behavior, especially when you use this weight loss strategy regularly. 

On the other hand, there are some case studies, stating that weight loss after fasting is more sustainable than weight loss after a low-calorie diet.

Overall score:6.5 out of 10

Vegan diet

As plant-based diets become more popular year after year, we write a lot about the vegan diet. Earlier this year we’ve even provided a 1200-calorie meal plan for vegans. Some researchers state that plant-based diets have great benefits for health. Other scientists show statistics proving that vegans are usually slimmer than omnivores. 

Weight loss on a plant-based diet is only possible when you’re in a calorie deficit. This means that you should still keep an eye on your portions and don’t gorge on high-calorie vegan products. Vegan does not equal low-calorie.

Requires medical supervisionNo, however medical advice is preferable
Overall health benefitsImproves health in a short term perspective, however, can lead to micronutrients deficiency in the long term.
Scientific researchScience proves that vegans do tend to have a lower BMI than omnivores. Some research also shows that a vegan diet can be beneficial for various health conditions.
Weight loss speed

6/10

Your weight loss will highly depend on the number of calories you consume.

Affordability

7/10

The affordability of your vegan diet highly depends on the season and the place where you live.

Restrictiveness (how easy it is to follow)

7/10

A vegan diet is quite restrictive and you will have to refrain from many products you used to eat. However, it doesn’t limit the amount of food you can eat. 

Weight maintenance and sustainability for life

6/10

Most vegans start to reintroduce animal products to their diet after several years of veganism due to vitamins or minerals deficiency. 

There is not enough data on weight regain among ex-vegans.

Overall score:6.5 out of 10

Body recomposition diet

Body recomposition is not about weight loss. It is about increasing your muscle mass and decreasing your body fat percentage at the same time. It does require some changes in your nutrition, like having a calorie deficit on days without workouts and adding more calories on workout days.

Its main downfall? It’s not for everyone. Only those who want to build muscle and are ready to work out will see results. 

Requires medical supervisionNo need for medical supervision
Overall health benefitsYou get all the benefits you would from decreasing your fat percentage and improving your fitness.
Scientific researchThere are just case studies proving the efficiency of body recomposition. For the moment, there are no solid scientific facts proving body recomposition is better than cutting and bulking cycles for fat loss and muscle growth.
Weight loss speed

3/10

Body recomposition is not about weight loss. It’s about simultaneous fat loss and building muscle. There might be no great changes on the scales but this diet is supposed to improve your physique.

Muscle building is a slow process and will take some time.

Affordability

7/10

This diet supposes that you eat more protein. Protein-rich products might be more expensive than carbs or fat sources.

Restrictiveness (how easy it is to follow)

7/10

This diet doesn’t cut your calories drastically, though it requires some changes in your macros ratio.

Weight maintenance and sustainability for life

8/10

People who add physical activity to their lives have higher chances of maintaining their new weight. What’s more, as on this diet you don’t cut your calories drastically, you don’t face metabolic adaptation and have more chances of eating enough and maintaining a lower body fat percentage.

Overall score:6.25 out of 10

The ketogenic diet

The traditional keto diet states that you should get 75% of your calories from fats, 20% from protein, and only 5% from carbs. 

However, the mechanism why you lose weight on the keto diet is not that clear. Fast weight loss might be explained by a calorie deficit you create by cutting off an entire macronutrient group. But keto diet followers state that fast weight loss is the result of the magical state of ketosis when your body utilizes fat stores as its main source of energy and doesn’t need carbohydrates any longer. 

Whatever the reason for weight loss is, there’s no doubt that the keto diet helps a lot of people to lose weight fast.

Requires medical supervisionNo, however medical advice is preferable. There are some health conditions when the keto diet is not recommended.
Overall health benefitsAccording to some research, it can have a positive effect on overall health. It also helps treat epilepsy.
Scientific researchScience shows that in a short perspective, a ketogenic diet can be even more efficient for weight loss than a low-calorie diet.
Weight loss speed

9/10

You can lose more than one pound a week. This is explained by the lack of carbs and as the result, fast water loss.

Affordability

6/10

The price of your shopping basket highly depends on the products you choose. Overall, the keto diet rich in meat, fatty fish, nuts, butter, oil, and cheese is more expensive than an average American or a common low-calorie diet.

Restrictiveness (how easy it is to follow)

4/10

Getting 75% of your calories from fat is not that easy! You will have to count your macros and refrain from most products just to keep up with your new macro goals.

Weight maintenance and sustainability for life

4/10

Research papers show that the ketogenic diet is not sustainable for a long time. As it is not sustainable, it can be hard for dieters to maintain their new weight when they stop following the keto diet.

Overall score:5.75 out of 10

Pegan diet

Developed by Dr. Mark Hyman, this diet is full of controversies. According to the author, it combines the best from the vegan and the paleo diet. It also forbids many food groups, divides food into “good” or “bad,” and promotes “clean eating.”

Requires medical supervisionNo need for medical supervision
Overall health benefitsThe food list allowed by this diet is supposed to improve health. It contains high-quality organic products and minimizes the consumption of processed food.
Scientific researchThere is no scientific evidence that this diet is somehow better or more efficient for weight loss or health than any other diet.
Weight loss speed

7/10

The weight loss speed highly depends on the number of calories you consume, however, as the diet is very restrictive and abandons some food groups, you can expect fast weight loss.

Affordability

4/10

The diet presumes you should eat only grass-fed meat, wild fish, and organic fruits and vegetables. It is not cheap.

Restrictiveness (how easy it is to follow)

5/10

Dairy, gluten, sugar, alcohol… The Pegan diet forbids a lot of products without a scientific explanation of why these food groups should be avoided. 

Weight maintenance and sustainability for life

6/10

The possibility that you will regain weight when you stop following this diet is quite high.

Overall score:5.5 out of 10

Keto + IF

One of the newest trends, the combination of the ketogenic diet and intermittent fasting protocols, is supposed to boost weight loss by stimulating ketosis and autophagy. 

As this weight-loss approach is quite new, there is not enough scientific data proving that this combination of diets is somehow more efficient than the ketogenic diet or intermittent fasting protocols used alone. 

Requires medical supervisionMedical advice is preferable. Both the keto diet and IF have their limitations. People with some health conditions should not try combining keto and IF.
Overall health benefitsThere is no strong scientific evidence that the combination of the ketogenic diet and intermittent fasting protocols will improve any of your health markers.
Scientific researchScience shows that in a short perspective, a ketogenic diet can be even more efficient for weight loss than a low-calorie diet.
Weight loss speed

9/10

There can be more than one pound a week weight loss due to water loss and the severe restrictiveness of these diets.

Affordability

7/10

That highly depends on the products you choose. Overall, combining keto and IF can be more expensive than following a low-calorie diet.

Restrictiveness (how easy it is to follow)

2/10

This is a combination of two highly restrictive eating patterns. You don’t just cut off carbs or eat during the narrow period. You do both.

Weight maintenance and sustainability for life

2/10

This approach is severely restrictive and for this reason, is not sustainable for life. As it doesn’t teach the dieters how to eat normally, weight maintenance is quite unlikely.

Overall score:5 out of 10

Summing up

Changing your life is difficult. Losing weight presumes that you will make changes in your eating habits and this can be challenging. However, you can make the weight loss process easier by choosing a diet that fits you. 

If there was only one piece of advice we can give it would be: Don’t push yourself too hard. Start with small changes, go slow, and your new body will stay for you as long as you want. Fast fixes might take you to your weight goal faster, but will you be able to sustain the new physique for long?

Choose sustainable approaches that are not overly restrictive, and in 2022 you will get to your dream body and will maintain it all year round!