Updated by Stephen Anton PhD on June 25th, 2020

In today’s society of weight-loss fads, many wonder what diet is best and why they should give it a shot. All of the diets say that they are the best, but how do they compare?

The top seven most popular diets were chosen by a systematic study to look at the scientific evidence of the effects of their weight loss outcomes (1).

Do they give you what is promised in the end?

How do they help with weight loss or muscle gains?

Below are the basics of these seven diets to showcase their plans and how they work in the body. Each has its positives and negatives to the world of weight loss.

The Atkins diet is a low-carb diet, usually recommended for weight loss. Proponents of this diet claim that you can lose weight while eating as much protein and fat as you want, as long as you avoid foods high in carbs.

Over the years, many studies have shown that low-carb diets without needing calorie counting are effective for weight loss and can lead to various health improvements.

The Atkins diet has four different phases:

Phase 1: Induction

Start with under 20 grams of carbs per day for two weeks

Eat high-fat, high-protein, with low-carb vegetables like leafy greens

These steps kick-start the weight loss

Phase 2: Balancing

Slowly add more nuts, low-carb vegetables, and small amounts of fruit back to your diet

Phase 3: Fine-tuning

When you’re very close to your goal weight, add more carbs to your diet until weight loss slows down

Phase 4: Maintenance

Here you can eat as many healthy carbs as your body can tolerate without regaining weight

Many skip the induction portion and start with plenty of fruits and vegetables to support a healthy lifestyle.

Dietary Approaches to Stop Hypertension (DASH) is an eating plan to lower or control high blood pressure. The DASH diet features menus with plenty of whole grains, vegetables, poultry, fish, fruits, and nuts.

What is the goal?

Reduce your sodium intake and instead eat a variety of foods that contain blood pressure-lowering nutrients like magnesium, potassium, and calcium.

Some tips are to snack on low sodium foods like nuts or unsalted popcorn. You can also include fruit for a snack or dessert. Opting for low-fat or skim dairy will benefit this approach as well.

The glycemic index, or GI, measures how a carbohydrate-containing food raises blood glucose.

Foods are ranked based on how they compare to a reference food — either glucose or white bread.

Low GI Foods (55 or less):

Sweet potato, corn, yam, lima/butter beans, peas, legumes, and lentils

100% stone-ground whole wheat or pumpernickel bread

Oatmeal (rolled or steel-cut), oat bran, muesli

Most fruits, non-starchy vegetables, and carrots

Pasta, converted rice, barley, bulgar

Medium GI Foods (56-69):

Brown, wild or basmati rice, couscous

Whole wheat, rye, and pita bread

Quick oats

High GI Foods (70 or more):

Short grain white rice, rice pasta, macaroni, and cheese from mix

Corn flakes, puffed rice, bran flakes, instant oatmeal

Pretzels, rice cakes, popcorn, saltine crackers

Russet potato, pumpkin

Melons and pineapple

White bread or bagel

Fat and fiber tend to lower the GI value of a food. The more processed it is, the higher the GI value, in general.

However, this is not true of all foods.

If you’re looking for a heart-healthy eating plan, the Mediterranean diet might be right for you.

The Mediterranean diet incorporates the basics of healthy eating — plus a splash of flavorful olive oil and perhaps a glass of red wine — among other components characterizing the traditional cooking style of countries bordering the Mediterranean Sea.

Most healthy diets include whole grains, vegetables, fish, and fruit. Most Mediterranean diets limit unhealthy fats.

While these parts of a healthy diet are tried-and-true, subtle variations or differences in proportions of certain foods may make a difference in your risk of heart disease.

This diet is popular for lowering low-density lipoprotein (LDL) levels of cholesterol, the “bad” cholesterol.

The Mediterranean diet emphasizes:

Eating primarily plant-based foods, such as fruits and vegetables, whole grains, legumes, and nuts

Replacing butter with healthy fats such as olive oil and canola oil

Using herbs and spices instead of salt to flavor foods

Limiting red meat to no more than a few times a month

Eating fish and poultry at least twice per week

Enjoying meals with family and friends

Drinking red wine in moderation (optional)

Getting plenty of exercise

Ornish Lifestyle Medicine has been scientifically proven to reverse the progression of even severe cases of coronary heart disease, hypercholesterolemia, high blood pressure, and type 2 diabetes.

It has even shown some results in slowing cancer growth. It is a specific diet plan for each individual based on genes.

There is a focus on eating good proteins, carbs, and fats and avoids eating bad proteins, carbs, and fats. There should also be a focus on eating foods in their natural form as they are found in nature and leaving out processed foods in any way.

Small frequent meals spread throughout the day will help you avoid hunger and keep your energy levels constant.

Calories are unrestricted for most in this plan unless you are trying to lose weight, and then there are some restrictions.

A paleo diet aims to return to a way of eating that’s more like what early humans ate. The diet consists of foods that in the past could be obtained by hunting and gathering.

The aim is to limit foods that became common when farming emerged about 10,000 years ago. The diet reasons that the human body is genetically mismatched to the modern diet that emerged with farming practices.

What foods to eat:

Fish, especially those rich in omega-3 fatty acids, such as salmon, mackerel, and albacore tuna

Oils from fruits and nuts, such as olive oil or walnut oil

Lean meats, especially grass-fed animals or wild game

Nuts and seeds

Vegetables

Fruits

What foods to avoid:

Legumes, such as beans, lentils, peanuts, and peas

Grains, such as wheat, oats, and barley

Highly processed foods in general

Dairy products

Refined sugar

Potatoes

Salt

The Zone diet doesn’t promise dramatic weight loss and usually results in 1 to 2 lbs in the first week. It is designed for long term loss and to reduce inflammation.

On the Zone diet, you get three meals and two snacks a day.

Each meal is a mix of:

Small amount of “good” fat, like olive oil, almonds, and avocado

Low-fat protein, like skinless chicken, turkey, or fish

Carbs (mostly fruits and veggies)

No food is completely banned, but if you’re a carb-lover, you may find getting used to the Zone plan challenging. It encourages you to think of bread, pasta, grains, and other starches as condiments rather than main or even side dishes.

Every meal on the Zone plan has the same proportions, 30% protein, 30% fats, and 40% carbs.

Most of the diets showed weight loss results, but Atkins had the most short-term results, long-term results, and clinical trials.

Overall, you should select a diet that most aligns with your specific goals and needs. It all comes down to consistency and following the guidelines as well as including exercise.