How Healthy Are They? The Most Popular Diets Of 2020

Diet trends come and go every year. Some last for decades, while others disappear within months. But being new doesn’t make diets a fad, and being popular doesn’t make them healthy. All diets assert that they’re the best–but are they?

It’s time to explore the most popular eating programs of 2020. What do studies have to say about these eating plans? Does cutting carbs help? Does removing meat improve the body? Discover what science has to say about the most popular diets of 2020.

The Mediterranean Diet

Bowls of pasta stem from the Mediterranean diet.
DeAgostini/Getty Images
DeAgostini/Getty Images

The Mediterranean Diet has appeared in dozens of health studies over the past several years. As the name suggests, the diet originates from countries bordering the Mediterranean Sea. It emphasizes plenty of produce, low amounts of lean protein, and olive oil as its primary fat source.

Because of its long list of scientific backing, the American Heart Association encourages this diet. After analyzing 85 studies, researchers have linked the Mediterranean Diet to a lower risk of heart disease, healthier weight, and longer living. Unlike other diets, it allows people to eat fat and bread.

The DASH Diet

Glycemic author takes a snack break to talk to students.
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The DASH Diet originated from research sponsored by the US National Institutes of Health. The eating plan is designed to lower blood pressure and reduce patients’ reliance on medications. DASH stands for Dietary Approaches to Stop Hypertension.

DASH emphasizes low sodium and high fiber. It includes fruits, vegetables, low-fat dairy products, legumes, and lean meats. According to the National Heart, Lung, and Blood Institute, a few studies have linked the DASH Diet to reduced cholesterol and blood pressure. Others follow the DASH plan to lose weight.


Vegan and vegetarian food are offered at a buffet.

Veganism has grown significantly over the years, according to a 2017 report. Unlike vegetarians, vegans exclude all animal products, including eggs, honey, butter, and bone broth. Protein replacements include nut butter, tofu, alternative milk, and legumes.

According to research in Critical Reviews in Food Science and Nutrition, veganism can stabilize blood sugar, regulate cholesterol, and even reduce the risk of cancer. However, vegans are at risk of a nutrition deficit. They must take care to eat enough vitamin B12, iron, calcium, and omega-3 fatty acids.

The Keto Diet

A woman shows off food that works for the ketogenic diet.
Jonathan Wong/South China Morning Post via Getty Images
Jonathan Wong/South China Morning Post via Getty Images

Despite the popularity of the Keto Diet (short for Ketogenic), it consistently ranks low on the U.S. News list of healthy diets. The eating plan formed as a way for children with epilepsy to experience fewer seizures. Over the past few years, it became a weight loss program for its high-protein, high-fat, and low-carb approach.

Many experts do not recommend Keto because it has many risks, especially if people over-emphasize the low-carb aspect. Kathy MacManus, Harvard’s director of the Department of Nutrition, lists many. It can harm your liver and kidneys with its high fat, result in nutrition deficits, and lead to brain fog.

The MIND Diet

Junk food diagrams are filled inside a black diagram of a brain.
Universal History Archive/Universal Images Group via Getty Images

As the name implies, the MIND Diet claims to improve brain function. By combining the Mediterranean and DASH diets, MIND aims to reduce the risk of dementia and keep the brain sharp. It promotes foods that scientifically encourage brain health.

MIND stands for Mediterranean-DASH Intervention for Neurodegenerative Delay. In 2015, researchers documented foods that help and harm the brain. On the MIND Diet, people avoid butter, fried food, sugar, red meat, and cheese. They eat whole grains, legumes, olive oil, nuts, berries, vegetables, and the occasional drink.

The Paleo Diet

An egg dish adheres to the paleo diet.
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Jonathan Wiggs/The Boston Globe via Getty Images

People on the Paleo Diet (short for the Paleolithic Diet) only eat what people consumed between 2.5 million to 10,000 years ago. Proponents claim that humans have not adjusted to modern food genetically, which many argue against. The diet emphasizes whole produce, meats, and fish that hunters and gatherers would have eaten.

Oddly enough, the concept behind Paleo is historically inaccurate. The diet removes grains, which Paleolithic people did eat back then. Still, there are some benefits to Paleo. A 2009 study claimed that Paleo improves symptoms of obesity and type 2 diabetes.


A market stand only sells plant-based food.
Ollie Millington/Getty Images

Vegetarians exclude chicken, pork, fish, and beef from their diet. Some allow eggs and milk, and others (pescatarians) allow fish. With over six million vegetarians in the U.S., the diet has become a health goal as well as an animal rights movement.

According to Harvard Health Publishing, some studies link vegetarianism to a lower risk of heart disease, type 2 diabetes, and cancer. However, vegetarians may not receive enough nutrients. Minerals from animal products, including iron, calcium, and vitamin B12, are scarce in this diet.

The South Beach Diet

Books on the South Beach Diet are displayed at Books & Books.
Gustavo Caballero/Getty Images
Gustavo Caballero/Getty Images

The South Beach Diet is another version of Keto that’s more flexible and less restrictive. Like Keto, it’s high in protein and low in carbs, but it doesn’t eliminate all carbs. Dieters have their picks of “good” protein and “good” carbs.

People on the South Beach Diet receive food delivered. The meals include full-fat milk, lean protein, nonstarchy vegetables, and no trans fat. Unlike Keto, South Beach was designed to help people lose weight while promoting heart health. Although it’s restrictive at first, the diet is reliable and healthy.

The Whole30 Diet

The original book on the Whole30 diet by Kirsten Buck sits behind a terracotta pot in a kitchen.

Unlike other diets, the Whole30 Diet only lasts for 30 days. It’s designed to change peoples’ eating habits by adjusting their palettes to healthier foods. Whole30 focuses on removing inflammatory foods that are linked to diseases, such as fried food, soda, and sodium-heavy meals.

Whole30’s creator, Melissa Hartwig, lists “clean” foods that people can eat throughout those 30 days. However, some dietitians argue against the Whole30 Diet. Some healthy whole foods, such as legumes, do not appear on the “clean” list. Plus, many assert that a 30-day eating plan isn’t long enough to be a diet.

The Anti-Inflammatory (Alkaline) Diet

A man holds a cup of blueberries.
Kirk McKoy/Los Angeles Times via Getty Images
Kirk McKoy/Los Angeles Times via Getty Images

The Anti-Inflammatory Diet (also called the Alkaline diet) is another plan based on the Mediterranean diet. Integrative medicine doctor Andrew Weil designed the program to lower inflammation in the body. According to him, reduced inflammation may delay the progression of chronic diseases.

For the most part, the Anti-Inflammatory Diet includes foods that most nutritionists recommend. Fresh produce, plant-based proteins, nuts, fatty fish, and whole grains are encouraged. Dieters avoid processed foods and pre-packaged, sodium-filled meals. However, there isn’t much research backing it up.

The Flexitarian Diet

A notebook about flexitarianism sits near fruits, vegetables, and red meat.

You may have heard about vegetarians and pescetarians; now, get ready for flexitarians. In 2008, dietitian Dawn Jackson Blatner published the book Flexitarian Diet, which promoted vegetarianism with permission to eat fish and meat once in a while. On this diet, people restrict meat, but they don’t give it up entirely.

The Flexitarian Diet encourages people to vary their protein sources and not rely so much on meat. Although few studies cover this diet, it has some benefits. In 2017, research in Frontiers in Nutrition said that Flexitarianism encouraged heart health, weight loss, and stable blood pressure in participants.

Intermittent Fasting

A clock is placed on a plate.
Blossoming Widow/Pinterest
Blossoming Widow/Pinterest

During Intermittent Fasting, people eat in cycles between long periods of fasting. Rather than emphasizing what you should eat, the diet highlights when you should eat. Intermittent Fasting has several schedules that people can follow, often featuring long fasts once or twice a week.

The diet became famous in 2012 after the documentary Eat Fast, Live Longer aired on BBC. According to Harvard Health Publishing, Intermittent Fasting effectively helps people lose weight, but it’s hardly different from any other diet. Because it’s hard to stick to, some people find it unsustainable.

The Volumetrics Diet

Food is placed on a scale.
Stephanie Asper/Pinterest

While other diets focus on reducing high-calorie foods, the Volumetrics Diet emphasizes high amounts of low-calorie foods. Developed by nutrition professor Barbara Rolls, Volumetrics highlights highly nutritious foods with low energy density. These include berries, lean meats, and nonfat dairy products.

Dr. Rolls designed Volumetrics based on research. Large observational studies link low-density foods with a reduced risk of diabetes, cancer, and heart disease. Many people go on this diet to lose weight healthily since it also encourages 30 to 60 minutes of exercise daily.

The Nordic Diet

Toast with mashed beats are on a tray.
New Amsterdam Market/Flickr
New Amsterdam Market/Flickr

The Nordic Diet stems from traditional cuisine in Denmark, Sweden, Finland, Iceland, and Norway. Unlike the Mediterranean diet, the Nordic plan allows a wide array of cooking oils and healthy fats. It also emphasizes buying nutritious foods from local vendors when possible.

People on the Nordic Diet limit red meats and animal fats. Instead, they receive protein from eggs, legumes, dairy, and lean meats. According to a 2014 study, the Nordic Diet lowers weight loss and blood pressure in obese people. However, the researchers noted that some dieters gained the weight back.

The Fertility Diet

A woman is four months pregnant.
ULISES RUIZ/AFP via Getty Images
Fairfax Media via Getty Images via Getty Images

As its name implies, the Fertility Diet first began to help women get pregnant. But since it emerged in 1991, the diet has focused more on healthy eating than fertility. It came about after an eight-year study on women and diet called the Nurses’ Health Study.

Like other eating plans, the Fertility Diet limits trans fats and carbs. Dieters eat more vegetable oils, iron-heavy foods, whole milk, and plant-based proteins. Many people try this diet because it isn’t too restrictive and can help shed weight.

The Raw Food Diet

Raw tilapia fish is seasoned over a wooden cutting board.
Roberto Machado Noa/LightRocket via Getty Images
Roberto Machado Noa/LightRocket via Getty Images

As the name implies, the Raw Food Diet restricts processed foods. These include pasta, coffee, tea, table salt, cooking oils, and processed meats. Some raw food eaters are vegan or vegetarian, but animal products are permitted as long as they haven’t been altered. Raw foodists also can’t heat anything above 118 degrees, and they mainly use dehydrators for cooking.

Proponents argue that the diet gives people more energy and a lower risk of disease. However, raw food can be dangerous. Several foods–such as buckwheat, kidney beans, and milk–are toxic when consumed raw.

The Ornish Reversal Plan

A plant-based dish represents the Ornish diet.

The Ornish Reversal Plan, also called the Ornish diet, claims to relieve or “reverse” symptoms of chronic illness. Dr. Dean Ornish, a researcher and founder of the Preventive Medicine Research Institute, created the program to slow down inflammation and disease progression.

Despite the diet’s popularity, many experts have refuted Dr. Ornish’s claims. For instance, the diet recommends consuming more carbohydrates–which Americans already over-consume. If left unmonitored, dieters could eat too little protein and fat, and they could experience dangerous nutrition deficits.

The Atkins Diet

A low-carb, high-protein plate illustrates the Atkins diet.
Vince Talotta/Toronto Star via Getty Images
Vince Talotta/Toronto Star via Getty Images

Since 1972, the Atkins Diet has promoted low-carb meals. Physician Dr. Robert C. Atkins created the plan to reduce obesity rates. On the Atkins diet, people avoid high-carb foods such as fried meals, vegetable oils, beans, starches, and certain fruits and vegetables.

Several researchers criticize the Atkins Diet for its adverse effects. Dr. Neal Barnard, president of the Physicians Commission for Responsible Medicine, says that diet is linked to colon cancer, osteoporosis, and kidney disease. The reason is that people tend to replace carbs with meat.

The Flat Belly Diet

A woman lifts weights.
Mikhail TereshchenkoTASS via Getty Images
Mikhail TereshchenkoTASS via Getty Images

The controversial Flat Belly Diet promises to help people lose weight quickly. The diet highlights monounsaturated fats (MUFAs) as the key to weight loss. The diet’s creators, registered dietitian Cynthia Sass and former Prevention magazine editor Liz Vaccariello, claim that dieters can drop pounds within a month.

Although some studies link MUFAs to weight loss, there is little evidence that they remove pounds so quickly. Critics of the diet point out that it has no evidence other than the original book, and that it may be too restrictive.

The TLC Diet

Yellow and orange split peas are arranged in a heart-shaped cookie cutter.
Roberto Machado Noa/LightRocket via Getty Images
Roberto Machado Noa/LightRocket via Getty Images

No, the TLC Diet doesn’t stand for Tender Loving Care–it’s Therapeutic Lifestyle Changes. The National Heart, Lung, and Blood Institute developed to diet to control cholesterol levels and improve heart health. On the diet, people reduce their intake of saturated and trans fats, replacing them with healthy monounsaturated fats.

The TLC program has other benefits, too. According to the Journal of Lipid Research, TLC assuages inflammation and promotes immune function in the body. In 2018, another study linked the diet to a reduced risk of type 2 diabetes.

The Nutritarian Diet

A fridge is filled with whole, healthy foods.

In 2011, family physician Joel Fuhrman published the book Eat to Live. The book promoted a six-week-long diet that’s high in nutrients, low in calories, and excludes processed foods. Nutritarianism, as it’s known, only allows unprocessed “nutrient-dense” meals with no animal protein.

Even healthy, processed foods, such as olive oil, are limited. Although the Nutritarian Diet doesn’t count calories, it’s still more restrictive than other diets out there. According to critics, Fuhrman’s claims that the diet reverses chronic illness and extends the lifespan are over-reaching.

The Body Reset Diet

Harley Pasternak, author of Body Reset Diet, sits on an exercise bike.
Colin McConnell/Toronto Star via Getty Images
Colin McConnell/Toronto Star via Getty Images

According to celebrity physiologist and nutrition expert Harley Pasternak, several stars have lost weight on the Body Reset Diet. This 15-day program requires people only to drink smoothies for the first couple of days. Gradually, people can reinsert solid foods that remain under a calorie limit.

The Body Reset Diet promises to “jump-start” your metabolism so you can eat less later. However, other health experts argue against this. The diet allows far fewer grains and protein than the USDA recommends. Plus, registered dietitian Chrissy Carroll asserts that people will gain back the weight after 15 days.

The Weight Watchers Diet

A weight watcher leader introduces herself to a client.
Eugene Gologursky/Getty Images for Weight Watchers
Eugene Gologursky/Getty Images for Weight Watchers

The Weight Watchers (WW) diet is one of the most popular eating plans in the world. Since it began in 1963, WW has grown into a multi-million dollar company. It assigns “points” to certain foods, allowing people to eat anything as long as they stay within the points. Sugary, fatty foods cost more, while healthy foods have fewer points.

WW can be expensive, but the community aspect keeps people accountable. The diet does not promote any healing abilities or cure, and it’s flexible. That said, regaining the weight is a risk, as it is with any diet.

The Engine 2 Diet

A bowl of hot cereal sits next to a book on the Engine 2 Diet.

After retiring from firefighting, professional athlete and medical scion Rip Esselstyn invented a new diet. The Engine 2 Diet opts for low-fat, “plant-strong” foods that combat diseases. During the diet, people gradually transition to veganism and cut out all processed grains and vegetable oils.

People who follow Engine 2 may struggle to meet their recommended protein and vitamin B-12 requirements. Because the diet is so restrictive, it’s not always sustainable. The founder’s claims that it “reverses heart disease” are also not fully backed by research.

The Jenny Craig Diet

The exterior of a Jenny Craig building is seen.
John Greim/LightRocket via Getty Images
Tim Boyle/Getty Images

Jenny Craig is a paid diet plan that connects people to dietary consultants. The advisors recommend meals between 200 to 300 calories, with snacks being between 150 to 200. Through the program, clients receive meals until they eventually learn to cook on their own.

In the International Journal of Obesity, one study concluded that people who complete the Jenny Craig program average a 7% lower weight than before. The longer people stick with it, the more weight they lose. However, the program is expensive.

The Optavia Diet

An Optavian meal cooks in a skillet.

Optavia is a meal replacement plan designed to help people lose weight. To restrict calories, the diet incorporates “fuelings” (shakes and protein bars) into six small meals per day. While dieters don’t count calories, they limit certain foods to a few servings per day.

Experts have pointed out that Optavia is similar to Medifast, which can reduce weight and blood pressure according to studies. Along with being expensive, Optavia includes an extreme and sometimes unhealthy calorie restriction, says registered dietitian Grace Derocha.

The Mayo Clinic Diet

Mayo Clinic's health care services stores is open in a mall.
Marlin Levison/Star Tribune via Getty Images
Marlin Levison/Star Tribune via Getty Images

Throughout the past few years, the Mayo Clinic Diet has consistently ranked high on the U.S. News diet ranking. It focuses on weight loss through research-based, sustainable eating. Because the diet doesn’t restrict or over-emphasize certain foods, it’s easier to follow long-term than other eating plans.

The weigh- loss experts at Mayo Clinic devised a food pyramid that dieters can follow. It follows “the basics” of healthy eating, says clinical instructor of biomedical sciences, Natalie Allen. It can also be tweaked to accommodate people with health complications.

The Dukan Diet

Raw steak is on a chopping block.
Natasha Breen/REDA&CO/Universal Images Group via Getty Images
Natasha Breen/REDA&CO/Universal Images Group via Getty Images

The Dukan Diet argues that calorie-counting doesn’t help people lose weight; instead, eating plenty of protein helps. French general practitioner Dr. Pierre Dukan published a book about the program in 2000, and it quickly became a bestseller. On the diet, people aim to achieve their “true weight” (or goal weight) through four phases of eating plans.

So far, no clinical trials have evaluated the Dukan Diet. It requires a long list of rules that make the program hard to follow, especially in the first two weeks that promise to drop ten pounds. Some experts question the effectiveness of the diet.

The HMR Program

A book of HMR risotto has been opened.

The Health Management Resources (HMR) Program is another meal replacement diet. Behavioral psychologist Lawrence Stifler developed HMR in the ’80s to be medically guided and help people transition their lifestyle. Replacements include shakes, hot cereals, protein bars, and full meals.

Although HMR provides meals, its foods are highly processed and often filled with artificial sugars. Research in the Annals of Internal Medicine was unable to determine the results of HMR. However, they stated that extremely low-calorie diets might increase the risk of gallstones.

The Zone Diet

A woman presents a booth about the Zone Diet.
Pablo Blazquez Dominguez/WireImage
Pablo Blazquez Dominguez/WireImage

The Zone Diet attempts to lower inflammation and stabilize insulin levels, focusing on antioxidants and omega-3 fatty acids. Biochemist Barry Sears developed the plan to help people lose weight and reduce “dietary inflammation.”

On the Zone, people divide their daily meals into one-third protein, two-thirds carbohydrates, and a small amount of fat. Starches and grains are recommended as side dishes rather than main courses. Beyond one 2015 study, there isn’t much research to support the Zone Diet reducing inflammation. However, its emphasis on unprocessed, whole foods is promising.