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April 12, 2021  |  Health & Wellness

Best diets of 2021: Which one is right for you?

Whether you’ve recently put on a few extra pounds or you want to make a significant lifestyle change, going on a diet is one of the most effective ways to lose weight and improve your overall health. But there’s a reason diets are notorious for failure – the trick is choosing one that is realistic for you. 

Let’s face it: food tastes good, and it’s a common way to comfort yourself. It’s not the enemy. Many diets require giving up some of your favorite foods, doing extensive meal prep, planning ahead when dining out, and even giving up parts of your social life like indulgent brunches and happy hours. 

We dug deep into all of the most popular diets of 2021 to break each down so that you can determine which one is right for you. Before you make any major dietary change, consult your doctor, especially if you have any health conditions.


How does the keto diet work?

Also known as a “low carb” or “carnivore” diet, the ketogenic, or “keto” diet is the latest craze. It is believed to help with weight loss, and a slew of health conditions, from diabetes to dementa. It’s based on consuming very few carbs and upping your protein and healthy fat intake, thus putting your body in a state of “ketosis”, boosting your metabolism. It is similar to the Atkins and other low-carb diets that have been around for decades. If followed correctly, it can also greatly reduce blood sugar and insulin levels.

What can you eat on the keto diet?

There are several variations of the keto diet, but the standard is a diet comprised of 75% fat, 20% protein, and 5% or less carbs. 

You can eat:

  • Meats and fatty fish

  • Eggs

  • High-fat dairy like butter, cheese and yogurt

  • Seeds and nuts

  • Healthy fats like oils and avocados

  • Low-carb veggies

  • Seasonings like salt, herbs, and spices

You cannot eat: 

  • Foods with added sugar or that are naturally high in sugar, like fruit

  • Grains and starches 

  • Unhealthy, processed fats

  • Alcohol

  • “Diet” foods like low fat snacks and sugar free desserts

  • Beans and legumes

  • Root vegetables and tubers

Is the keto diet right for me?

The keto diet works best if you:

  • Prefer meat-based proteins

  • Are diabetic

  • Want to lose weight


The keto diet is best used as a temporary diet to lose weight, improve health issues, or reset the body after a period of unhealthy habits. Because it is so restrictive, it is difficult for most to stick to it over the long term. Success largely depends on healthy, balanced choices (versus overloading on any one food).

Our favorite resources for the keto diet


How does the Whole30 diet work?

This diet is all about eating whole, natural foods, eliminating all foods commonly found to cause inflammation. Its creator, Melissa Urban describes it as “a short-term reset, created to help you curb your cravings and bad habits, boost your metabolism, heal your digestive tract, and calm your immune system.”

What can you eat on the Whole30 diet?

Opt for almost all whole foods (no ingredients and unprocessed)

You can eat: 

  • Meat and seafood

  • Eggs

  • Fruits and vegetables

  • Nuts and seeds 

  • Herbs, seasonings, spices (check ingredients, though)

You cannot eat: 

  • Grains of any kind

  • Anything with added (not naturally occuring) sugar

  • Dairy

  • Alcohol

  • Legumes

  • Soy

  • Careegnan, sulfites, or MSG

  • Baked goods or “faux foods” even if all ingredients are Whole30 compliant

Is the Whole30 diet right for me?

While weight loss often results from strict adherence to Whole30, ultimately this diet is more for those who have developed some poor eating/drinking habits or who suspect they might have some sensitivities to certain foods. 


Whole30 is an extremely restrictive diet and can be a big challenge to stick with. It’s more of a short-term reset for your system than a real lifestyle change. We recommend reintroducing the off-limits foods while on Whole30 gradually when the diet is over, both to avoid weight gain and bloating and to more accurately pinpoint what foods may upset your body.

Our favorite resources for the Whole30 diet


How does the Mediterranean diet work?

This diet emphasizes heart-healthy foods, and even gets the approval of medical professionals. recommends this as a good diet option that “blends the basics of healthy eating with the traditional flavors and cooking methods of the Mediterranean.”

What can you eat on the Mediterranean diet?

The Mediterranean diet focuses on foods known to reduce one’s risk for cardiovascular disease, avoiding foods that can contribute to poor heart health (artery clogging fats and processed foods that the body can’t process well, mostly).

You can eat:

  • Fruits and vegetables

  • Lean proteins like fish

  • Seeds and nuts

  • Healthy, natural fats like olive oil 

  • Lots of herbs, garlic, pepper and other low-sodium seasonings

  • Whole grains

You cannot eat: 

  • Processed/junk foods

  • You can still eat red meat, but it should be minimal

  • You can only eat small amounts of dairy

  • While a glass of red wine is ok on occasion, alcohol consumption should be minimal

Is the Mediterranean diet right for me?

If you don’t want any food groups off limits, this is probably one of the best diets. The key to losing weight on it, though, is small portions and savoring high quality food.


This is one of the healthiest diets that can be a permanent diet change. Medical professionals support it, and it is much less restrictive than other diets. However, it doesn’t usually lead to rapid weight loss (also a plus because it’s more sustainable and healthy).

Our favorite resources for the Mediterranean diet


How does the paleo diet work?

It uses the idea of only eating what was available food back in the Paleolithic era (and a few other foods are allowed unless you’re being very strict), so it is also called the “caveman” diet. According to Healthline, “following a whole food-based diet and leading physically active lives, hunter-gatherers presumably had much lower rates of lifestyle diseases, such as obesity, diabetes and heart disease.”

What can you eat on the paleo diet?

On this diet, you will eat and drink what would have been readily available via hunting and gathering – but other more modern foods and beverages can be allowed, too. You want to eat whole foods, avoiding processed foods and certain ingredients.

You can eat:

  • Meat and seafood

  • Eggs

  • Fruits and vegetables (with some restrictions)

  • Nuts, seeds

  • Healthy fats from things like olive oil

  • Herbs, seasonings

You cannot eat: 

  • Although some allow some alcohol, it should be avoided

  • Dairy, although a more lenient version allows some full-fat cheese and butter

  • Processed/junk foods

  • Artificial ingredients

  • Sugar

  • Legumes

  • Grains

  • Trans fats

Is the paleo diet right for me?

It’s usually used short-term for weight loss or muscle-building goals in conjunction with a fitness regimen, but it can also be a healthy long-term diet, especially if the foods it does not allow are triggers for existing health issues like diabetes and food allergies or intolerances.


The paleo diet is well-loved by those who also want to use a diet in conjunction with consistent workouts for improved fitness and weight loss, so if you’re a gym rat or a CrossFit junkie, this might work well for you.

Our favorite resources for the paleo diet

Intermittent fasting

How does intermittent fasting work?

It’s not technically a diet; intermittent fasting serves to give your overall health, namely your ability to metabolize food properly, a boost by not eating during a set period of hours every day (usually eight to sixteen hours from mid-evening until the morning).

What can you eat when you’re not fasting?

Usually anything, although eating whole, unprocessed foods in balanced moderation and avoiding junk food is advisable if weight loss is your goal.

Is intermittent fasting right for me?

If your primary issue with healthy eating habits is snacking too often or eating when you can’t sleep, this can be a very good “diet” to try. A Harvard study found, however, that the trick to weight loss success is a limited eight-hour window during which you can eat (for example, you only eat between 9 a.m. and 5 p.m.). Those who eat during a longer period (usually 12 hours) did not lose as much weight in this study.


Most can benefit from intermittent fasting, which requires no special foods, is free, and is the least restrictive when it comes to what you can eat. But, frequently fasting for long periods of time has shown to have some adverse effects for women as compared to men, such as hair and mood changes.

Our favorite resources for intermittent fasting


How does the DASH diet work?

With appropriate portion sizes and balanced meals, the DASH (dietary approaches to stop hypertension) diet aims more at improved health than weight loss. The Mayo Clinic describes it as “a lifelong approach to healthy eating that's designed to help treat or prevent high blood pressure (hypertension).” 

What can you eat on the DASH diet?

It’s all about portion control and balanced meals, with an emphasis on heart-healthy foods. One of the main restrictions is your sodium intake, which can be no higher than 2,300 mg per day on a less restrictive diet, and no more than 1,500 mg on the most restrictive version of DASH.

You can eat:

  • Whole grains

  • Fruits and vegetables

  • Low-fat dairy

  • Fish

  • Lean meats (mostly poultry)

  • Legumes

  • Nuts and seeds

You cannot eat: 

  • While still allowed, red meat, sweets, and fats should be eaten in very small amounts on occasion

  • Avoid trans and saturated fats and sodium

  • Try not to drink alcohol and caffeine, which raise your blood pressure

Is the DASH diet right for me?

If you have a personal or family history of heart issues (or you are at a high risk due to lifestyle factors like obesity or a sedentary lifestyle), this can be a very smart diet, but only if followed as a lifestyle change.


If you want to reap all the benefits this diet can provide, DASH is meant as a lifestyle change, not a temporary diet plan.

Our favorite resources for the DASH diet


How does the low-FODMAP diet work?

FODMAP stands for Fermentable Oligo-, Di-, Mono-saccharides And Polyols. According to Healthline, “a diet low in fermentable carbs known as FODMAPS is clinically recommended for the management of irritable bowel syndrome (IBS).”

What can you eat on the low-FODMAP diet?

This diet is very focused on eliminating foods that trigger digestive upset, so it can be quite restrictive. It is best to eat whole foods (only one ingredient).

You cannot eat: 

  • Oligosaccharides (rye, wheat, legumes, certain fruits and vegetables like garlic and onions)

  • Disaccharides (most dairy, including yogurt, milk and soft cheeses)

  • Monosaccharides (fruit such as figs and mangoes; sweeteners with fructose)

  • Polyols (some fruits and low-calorie sweeteners)

Is a low-FODMAP diet right for me?

If you have digestive issues such as frequent diarrhea, stomach aches, indigestion, gas, and bloating, a low-FODMAP diet might help relieve these symptoms.


While not intended for weight loss, a low-FODMAP diet may result in some, although changes in your appearance will likely be the result of less bloating and water retention.

Our favorite resources for the FODMAP diet


Katie Reseburg is the editorial director for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.

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