Popular Diets Reviewed by Dietitians and Nutritionists

Popular Diets Reviewed by Dietitians and Nutritionists

Popular Diets Reviewed by Dietitians and Nutritionists

By: Julie Mancuso, founder of JM Nutrition, registered dietitians and nutritionists at JM Nutrition. Learn more about our team.


In this post:


  • Why do people diet?
  • Keto Diet review

  • Paleo Diet review

  • Atkins Diet review

  • Anti-inflammatory diets (Mediterranean & DASH) reviews

  • Intermittent fasting review


Many popular diets exist today. Some are approved by healthcare organizations, while many others fall under the fad diet umbrella and, at the time of writing, are not backed by regulated health professionals. Our team of registered dietitians and nutritionists has sifted through the evidence, including relevant studies and research, and put together a list of popular diet reviews. Each diet analysis includes the origin of the diet, associated health benefits and drawbacks, important considerations, and the verdict of our dietitians and nutritionists: recommended or rejected.

But, before we get to the popular diet reviews by our team of nutritional practitioners, let’s first examine the reasons why people diet.


Why do people diet?

There are many reasons why people decide to try various diets. Here are some of the more common ones.

Quick fix

Some people see diets simply as a quick fix for some health-related matter. Those who experiment with various diets (for example, weight loss) are often more interested in the short-term rather than the long-term. Simply put, they want relatively immediate results, no matter what the goal(s).

Weight loss

Perhaps the most common hasty remedy is dieting for weight loss.

In many cases, however, weight loss may be a complicated, multi-layered matter. It may require longer care of a health professional. Although this can vary, for weight loss to be healthy, many factors have to be taken into consideration. This is what our dietitians and nutritionists for weight loss do when they counsel clients.

It is no doubt important to ensure that while you are losing weight, your diet is nutritionally balanced. Many people who diet often disregard this fact and elect to skip various foods and even entire food groups. Doing so may be detrimental in the long-run.

Why You Should Work with a Weight Loss Coach

Following trends

Some people also turn to popular diets because they simply love trends. To some, having the latest or newest thing helps them feel ‘in’ or hip. These people may have their ears to the ground, always aware of the most current trend. Having this mindset may make it more likely that you try the newfangled diet that people rave about.


Surely, vanity is another reason why people may follow popular diets. For example, if the goal is to lose weight simply to look better, a fad diet may promise to bring about results rather quickly. As we alluded to before, in these cases prioritizing superficial results over long-term health and nutritional balance is the driving force.

Superficial appearance of health

A close cousin of vanity, superficiality also contributes to why people diet. To some, outward appearance of health is of primary concern. Overall health, nutrition and well-being, however, need to be examined from more of a holistic standpoint, inwardly and outwardly. Sure, you can be fit, lean and/or muscular, but you may suffer from nutrient-deficiencies, digestive distress or even disordered eating–things that may not be easy to spot at first glance.

Societal pressures

Both, men and women face various societal pressures to adhere to norms and often unrealistic and unattainable ideals to look a certain way. This has been perpetrated for years by media and the diet culture, shaping the minds of most people. The overwhelming pressure that some people feel to be thin, as an example, can and does lead to disordered eating patterns. It can also lead people to take short-cuts (read: fad diet) to attain this idealized version of themselves.

Mirroring others

Furthermore, some people undertake popular diets simply because they unconsciously imitate the behaviour of others. This phenomenon is called mirroring. When these people see their friends and family follow various diets, they may be inclined to try the diets themselves.

When people see something often enough, they begin to see it as a norm. As a result, they are more likely to engage in the same behaviour.

Athletic needs

Some people, on the other hand, may engage in some form of popular diet or fad for athletic reasons. This is something that our sports dietitians see from time to time.

For example, certain athletes may engage in restrictive eating behaviour in order to shed weight, be it for some form of competition or not.

Health conditions

Various health conditions may also prompt people to follow certain diets. We’ll address this in greater detail a little later in the post.


Popular Diet Reviews

Our dietitians and nutritionists have reviewed a number of these popular diets by examining the benefits, drawbacks and important considerations. They also provide a verdict on whether or not each popular diet is recommended.

Let’s take a look at some of these popular diets: 


1. Ketogenic Diet

No popular diet review would be complete without an examination of arguable the most popular diet at the time of writing: the Ketogenic diet.

What is the Ketogenic Diet?

Keto diet calls for the consumption of high-fat foods while drastically reducing the intake of carbs. In other words, it’s a high-fat (often 70-80%), very-low-carb (5-10%) diet, which comprises approximately 20-25% protein.

How does the Ketogenic Diet work?

Keto diet drastically reduces carb intake and replaces it with fat. This reduction in carbs puts your body into a metabolic state called ketosis. Your body then burns fat for energy, since it doesn’t have much glucose. It also turns fat into ketones in the liver, which can supply energy for the brain.

Benefits of the Ketogenic Diet


Drawbacks of the Ketogenic Diet

  • may lead to nutrient-deficiency
  • too restrictive for carb lovers
  • may be harmful for those stricken with heart disease, high cholesterol Related: dietitian for cholesterol management
  • keto flu (What is keto flu?)
  • constipation
  • kidney stones (Consistently high intake of animal proteins makes your urine more acidic and increases the amount of uric acid being excreted, potentially making you more susceptible to kidney stones.)
  • not ideal for athletes (Carbs are primary source of fuel for high-intensity training and various endurance activities.)

Related: Nutritional support for endurance athletes


Interesting fact about Keto Diet

Did you know that the keto diet was developed in the 1920s to treat epilepsy in children where medication was ineffective?

Learn more about keto and epilepsy.

Does the Keto Diet work?

No reputable long-term studies have been conducted on the effectiveness and health benefits of the keto diet.

Our verdict on the Keto Diet

Not recommended.


2. Paleo Diet

What is the Paleo Diet?

According to Mayo Clinic, a Paleo Diet is a dietary plan based on foods similar to what might have been eaten during the Paleolithic era or early Stone Age, which dates from approximately 2.5 million to 10,000 years ago.

In other words, the Paleo Diet places focus on foods that in the past could be obtained by hunting and gathering. At the same time, the diet limits foods that became common when farming emerged about 10,000 years ago. These foods include dairy products, legumes and grains.

Paleo Diet: What’s the reasoning?

In a nutshell, the goal of a Paleo Diet is to return to a way of eating that’s more like what early humans ate during the mentioned age. According to Mayo Clinic, the diet’s reasoning is that “the human body is genetically mismatched to the modern diet that emerged with farming practices.” This idea is often referred to as the discordance hypothesis.

Discordance hypothesis explained

The Mayo Clinic goes on to explain the hypothesis as follows:

“Farming changed what people ate and established dairy, grains and legumes as additional staples in the human diet. This relatively late and rapid change in diet, according to the hypothesis, outpaced the body’s ability to adapt. This mismatch is believed to be a contributing factor to the prevalence of obesity, diabetes and heart disease today.”

Why is the Paleo Diet so popular?

In relatively recent years, the Paleo Diet has been popularized by many celebrities who continue to tout its effectiveness.

Jessica Biel, Matthew McConaughey, Miley Cyrus, Kanye West, Gwyneth Paltrow, Phil Mickelson and many others, have tried and found success on the Paleo Diet.

What to eat on the Paleo Diet

  • fruits
  • vegetables
  • nuts & seeds
  • lean meats, esp. grass fed & wild game
  • fish
  • oils (e.g., olive)


What foods to avoid on the Paleo Diet

  • grains
  • legumes
  • dairy products
  • refined sugar
  • salt
  • potatoes
  • highly processed food


Paleo Diet benefits

  • improved glucose tolerance
  • better blood pressure control 
  • lower triglycerides
  • weight loss
  • better appetite management


Paleo Diet drawbacks

  • potential lack of fibre, vitamins & nutrients (The absence of whole grains and legumes, which are good sources of fibre, vitamins and other nutrients, can lead to insufficiency.)
  • potential lack of protein & calcium (A diet devoid of dairy products can lead to insufficient protein and calcium intake.)
  • not as easily accessible (Some of the foods may not be easily accessible in some regions or countries.)
  • more expensive
  • there are many factors to consider when we think of how we developed and evolved from age to age


Does the Paleo Diet work?

Although the diet can be effective in some situations, it may bring about deficiencies in nutrients. As a result, these deficiencies may negatively impact health.

Our verdict on the Paleo Diet

Not recommended.


3. The Atkins Diet

What is the Atkins Diet?

Atkins Diet is a low-carb diet that focuses on eating protein and fats without the need for calorie counting.

The Atkins Diet was originally promoted by Dr. Robert C. Atkins, who wrote a best-selling book about it in 1972. The book has sold over 12 million copies and has been dubbed “the best selling fad diet book ever written”.

Benefits of Atkins Diet

  • lower insulin & blood sugar levels
  • weight loss
  • calls for the consumption of hearty foods
  • no calorie counting is involved


Drawbacks of Atkins Diet

  • hard to sustain for those accustomed to carb-heavy meals
  • restriction of certain nutrients
  • inadequate fibre intake (Restricting carbohydrates on the Atkins Diet may lead to insufficient fibre intake, which is known to protect against heart disease and certain types of cancer, helps to regulate appetite and supports gut motility and healthy gut microbiota. A large portion of the fibre in our diets comes from whole grains and whole grain products such as breads and pastas. These foods are restricted on the Atkins Diet.)
  • potentially raised cholesterol
  • not for disordered eaters (Some people may become fixated on restrictive eating behaviour and carb counting, potentially leading to a negative relationship with food.) Related: dietitian for disordered eating
  • requires the counting of net carbs


How to calculate net carbs

To calculate net carbs, take a food’s total carbs and subtract:

a) Fibre

Since our body doesn’t have the enzymes to break down fibre, it passes through our digestion system unchanged.

b) Sugar alcohols

It’s also important to note that sugar alcohols such as xylitol and erythritol need to be subtracted. Sugar alcohols taste sweet, but their molecular structure is slightly different from that of sugar molecules, which leaves sugar alcohols indigestible.

Additionally, certain sugar alcohols do impact blood sugar. For this reason, you should factor them into your net carb count if you eat a large amount or are diabetic.

Why net carbs matter

Carb consumption is no doubt fine, in moderation. In fact, most people do better with some high-quality carbs in their diet.

However, excess carbs—and especially refined carbs such as bread, pasta, sugars, and so on—can:

  • spike your blood sugar
  • cause inflammation
  • trigger food cravings
  • potentially disrupt hormones
  • affect gut bacteria
  • potentially contribute to obesity
  • lead to insulin resistance, diabetes and metabolic syndrome 

Related: How to Cut Carbs


Atkins Diet: What’s the reasoning?

The premise behind the Atkins Diet is that when you keep net carbs low enough—under about 50 grams a day—your body goes into ketosis: a state in which you shift from burning glucose, or carbs, for energy to burning fat, including body fat. We mentioned this when we discussed the keto diet.

Does the Atkins Diet work?

Again, the Atkins Diet does work in some situations, even long-term. It, however, carries too many drawbacks for it to be a balanced, sustainable way of eating conducive to overall health.

Our verdict on the Atkins Diet

Not recommended.


4. The Anti-Inflammatory Diet

What is the anti-inflammatory diet?

It’s a fact that some foods contain ingredients that can trigger or worsen inflammation. As such, the purpose of the anti-inflammatory diet is to prevent and/or combat this inflammation.

Consequently, an anti-inflammatory diet favours fruits and vegetables, foods containing omega-3 fatty acids, whole grains, lean protein, healthful fats, and spices. On the other hand, it discourages or limits the consumption of processed foods, red meats and alcohol.

Discover more about food and inflammation.

Types of the anti-inflammatory diet 

Undoubtedly, two of the most popular diets that are anti-inflammatory in nature are the Mediterranean and DASH diets.

Related: Dietitian for anti-inflammatory diet


What is the Mediterranean Diet?

Simply put, the Mediterranean Diet is a heart-healthy diet that includes foods consumed by people who live in the countries around the Mediterranean Sea, such as Italy, Spain, Greece, Turkey and so on.

When it originated in the 1960s, the Mediterranean Diet only focused on the cuisines of Greece, Turkey, Italy and Spain. Since then, however, it has incorporated other cuisines from the Mediterranean, such as those of the Levant (Levant: modern-day Israel, Jordan, Lebanon, Syria, Palestine, etc.) and North Africa.

What to eat on the Mediterranean Diet

  • fruits
  • vegetables
  • whole grains
  • heart-healthy fats
  • legumes
  • oils (e.g., olive)
  • nuts & seeds


What foods to avoid on the Mediterranean Diet

  • processed foods
  • packaged & frozen foods
  • refined grains
  • added sugar
  • butter
  • alcohol (other than wine)

Furthermore, it’s worth noting that the Mediterranean Diet does not carry strict rules or regulations, per se. It’s not a diet in the strictest sense of the word, but more a way of eating. Because the diet is rich in flavourful ingredients such as fruits, vegetables, whole grains, heart-healthy fats and so on, researchers noted that these people were exceptionally healthy and had a low risk of many chronic conditions.

This infographic courtesy of Medical News Today accurately illustrates the gist of the Mediterranean Diet.

Mediterranean Diet benefits

  • promotes heart health (Research shows that the Mediterranean Diet may even be linked to a lower risk of heart disease and stroke. Other research shows that it could also help lower levels of diastolic and systolic blood pressure to support heart health.)
  • protects brain function (According to the National Institute on Aging and the journal Neurology the Mediterranean diet could be beneficial for brain health and may even protect against cognitive decline as you get older.)
  • nutritionally balanced
  • full of flavour
  • may reduce inflammatory markers
  • may prevent cognitive decline

Related: Dietitian for brain health


Mediterranean Diet drawbacks

  • not particularly effective for weight loss
  • may potentially lead to lower levels of iron
  • may potentially result in lower levels of calcium
  • may be expensive for some
  • time consuming
  • may lead to the overuse of alcohol


Mediterranean Diet fact

Did you know that the Mediterranean Diet regularly tops the list of the best diets overall in the annual U.S. News & World Report?

The panel of nutrition, health and medical experts routinely analyzes 40+ diets and ranks them according to their overall health benefits and value. The Mediterranean diet came out on top once again in 2022.

Does the Mediterranean Diet work?

As long as foods such as carbs and alcohol intake are moderated, this heart-healthy, balanced diet works.

Our verdict on the Mediterranean Diet



What is the DASH Diet?

The DASH diet is a healthy-eating plan designed to help treat or prevent high blood pressure (hypertension). DASH stands for Dietary Approaches to Stop Hypertension.

The U.S. News & World Report ranked the DASH Diet as the second best diet.

How does the DASH Diet work?

The DASH diet includes foods with nutrients that help control blood pressure.

These nutrients are:

a) Calcium

Calcium-rich foods include dairy products, almonds, anchovies, cooked spinach, fortified orange juice, beans, tofu prepared with calcium sulfate, et al.

b) Potassium

Most fruits and vegetables generally have some potassium. Some examples of these foods include banana, avocado, potato and tomato. Whole grains can also contain some potassium, as can oatmeal, quinoa, whole grain bread and cooked brown rice.

c) Magnesium

Foods that contain substantial magnesium include pumpkin seeds, chia seeds, almonds, peanuts, cashews and oatmeal, amongst others.

What ingredients does the DASH Diet limit?

While the DASH Diet focuses on the inclusion of the aforementioned nutrients, it also limits foods that are high in sodium, saturated fat and added sugars.

Benefits of the DASH Diet

  • effective at managing hypertension
  • generally flexible
  • accessible
  • nutritionally balanced
  • backed by major health organizations


Drawbacks of the DASH Diet

  • not designed for weight loss
  • requires food tracking (e.g., servings)
  • may not be appropriate for everyone (e.g., patients with chronic kidney or liver disease)


Does the DASH Diet work?

The DASH Diet can be effective in managing hypertension

Our verdict on the DASH Diet


And, if you require help from a dietitian to manage high blood pressure, by all means, get in touch with us, and we will gladly help.


5. Intermittent Fasting

What is intermittent fasting?

Intermittent fasting is cycling between eating and fasting. In other words, you fast or abstain from eating for a given period of time, eat, and then fast once again.

Consequently, intermittent fasting is not a diet, per se, but more of a relatively recent trend. What’s more, unlike other diets that primarily focus on what to eat, intermittent fasting focuses on when to eat.

So let’s take a look at what it is exactly.

How does intermittent fasting work?

As stated, intermittent fasting involves a period without eating. After hours without food, the body exhausts its sugar stores and starts burning fat. This is often referred to as metabolic switching.

According to John Hopkins University, intermittent fasting works by prolonging the period when your body has burned through the calories consumed during your last meal and begins burning fat.

Various intermittent fasting schedules exist. You can learn more about it here: Intermittent Fasting: Benefits, Drawbacks and Important Considerations

Benefits of intermittent fasting

  • resting of the digestive system (related: digestive health dietitians)
  • taking a break from the ingestion of inflammatory foods
  • potential weight loss

Related: Dietitian for weight loss


Drawbacks of intermittent fasting

  • may lead to overeating during the eating periods
  • potentially detrimental to those who are nutrient-deficient
  • not recommended for hypoglycemia
  • may not work well for certain elite athletes who require constant energy Related: How to Increase Energy Levels


Does intermittent fasting work?

Although a systematic review of 40 studies, including Harvard University, found that intermittent fasting was effective for weight loss, more high-quality studies including randomized controlled trials with follow-up of greater than one year are needed to ascertain long-term effectiveness. 

Our verdict on intermittent fasting

Undecided. We’re sitting on the fence here.



As we always say, we are all made differently, have varying dispositions, dietary conditions, preferences, lifestyles, cultural and religious backgrounds, budgets, and so on, that our eating habits should reflect that. Because we are so different, our approach to eating centres around personalization–something fad diets are not.

Although some diets have practical health benefits, they also possess many drawbacks. For this reason, we don’t recommend most diets, with exceptions. Rather, we favour a personalized approach to health.

Popular diet reviews take-away

In the end, you can take positive elements from each diet and apply them to your individual situation. These are all good elements that can be incorporated into our lives.

From the Ketogenic Diet: Eliminate sugar.

From the Paleo Diet: Eat fruits, vegetables, nuts & seeds.

From the Atkins Diet: Reduce carb intake to lower insulin & blood sugar levels.

From the Mediterranean Diet: Eat heart-healthy fats & enjoy the nutritional balance.

From the DASH Diet: Take in adequate amounts of potassium, calcium & magnesium to help manage hypertension.

From intermittent fasting: Provide your body with a rest from the ingestion of inflammatory foods.

Last, we hope that the above diet reviews provided some insight on some of the most popular diets out there today.

If you require a personal in-person appointment or would like to engage our online dietitian services, contact us or book a free consultation


Other Popular Posts:

Nutrition Myths vs. Facts

Pros And Cons Of Keto Diet

Gut Health 101

Factors That Influence Food Choices


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JM Nutrition is a nutritional counselling service by registered dietitians, nutritionists and health and nutrition coaches in Canada. Main office: nutritionist Toronto.

Author: Julie Mancuso

Julie Mancuso


Julie Mancuso is a graduate of the University of Toronto, founder and owner of JM Nutrition, a nutritional counselling service by registered dietitians and nutritionists. For 15+ years, JM Nutrition has helped thousands reach their health, wellness and nutrition goals. Julie and her team regularly lend their expertise to a variety of health publications such as Reader's Digest, Livestrong, Business Insider, Food Network, Today's Parent, MyFitnessPal, Toronto Star, Elle Magazine, Best Life, Weight Watchers and many more.