Weight loss trends come and go. Some diets work for many and are even beneficial to the body. On the other hand, a few weight loss plans may seem like they work for some, but they’re actually some of the unhealthiest diets out there!

The Two Unhealthiest Diets, According to Experts

Most of us have a “fitspiration” or body goal. Whether you want to bulk up, get lean, or lose weight, you’ve probably been told that working to achieve your dream physique doesn’t stop after exercising — because they say that the real test begins in the kitchen! However, even if you’re disciplined enough to stick to your diet, you might be following certain meal plans that are considered to be one of the unhealthiest diets out there.

Check out below the two unhealthiest diets that people follow.

Keto or Ketogenic Diet

How and why the keto diet works for some

People need carbohydrates as a source of energy. But with the keto diet, you’re supposed to drastically reduce carbs with fat. The fat you consume is supposed to be where your body will get its energy from. When this happens, your body will turn fat into ketones and undergo ketosis. Once your body is in the state of ketosis, it will then source energy from your stored fat. As a result, you will lose weight.

The keto diet can work for some who are at risk or suffer from diabetes. Since carbs contain glucose — which the body needs — limiting the consumption of sugar can be beneficial to their insulin levels. In a study by Diabetes Medicine, most Diabetes 1 patients who participated in the study (and followed the ketogenic diet) reportedly had “excellent levels” of blood sugar.

Additionally, Dr. Debra Sullivan of the Department of Dietetics and Nutrition at KU School of Health Professions, told the University of Kansas Medical Center, “As a dietitian and a nutrition scientist, we often don’t like to cut out whole food groups. And it’s not something I would recommend to the general population. But certain populations can benefit,”

The hidden perils of the keto diet

The keto diet is a form of extreme diet. Because consumption of carbs is extremely limited, people typically consume too much protein and fats — this can make a person at risk for heart attacks and other coronary heart diseases, as too much fat can clog the arteries. Furthermore, carbs and fiber are also almost non-existent in the keto diet — this can cause a significant drop in blood sugar levels, as sugar (glucose) is typically the human body’s main source of energy.

Additionally, a body usually enters a ketosis state even if we don’t try — sleeping alone can make the body achieve this state. According to Dr. Neel Chokshi of the Sports Cardiology and Fitness Program at Penn Medicine, (regarding the keto diet) “I try to get people to avoid extremes for extended periods of time, as the long-term effects of prolonged ketosis on the body are unknown.”

The keto diet has also grown so popular, that misinformation (or lack of information) already started to spread. Dr. Debra Sullivan noted, “On keto, we are increasing the amount of fat in someone’s diet, but we need to make sure it’s a healthier type of fat.”

Paleolithic, Paleo, or Caveman Diet

How the paleo diet can be healthy (to an extent)

Natural foods are always better than processed ones. The paleolithic or paleo diet consists of foods that were eaten by humans during the paleolithic times (about 2 million to 10,000 years ago) before agriculture or farming was invented. This means your diet is basically restricted to what you can hunt back then.

The philosophy behind the paleo diet is that the human body will thrive best if you only consume what early humans ate — as the human body is predisposed to utilizing only what our ancestors consumed. Therefore, grains, legumes, starches, refined sugar, and everything else that is farmed aren’t allowed in the caveman diet.

The paleo diet can be effective in weight loss as carbohydrates and other sources of sugar are limited — such as potato chips, soda, and to some, dairy products. Furthermore, the paleo diet can be healthy if the follower of this diet makes sure that they have an abundance of fruits and vegetables in their daily menu.

Problems that might arise when following the paleo diet

A person who’s under a paleo diet program can add too much protein to their diet, which can increase their cholesterol levels. Moreover, according to an article by UC Davis, since the restriction of dairy products is disputed, those who don’t have them added to their diet can suffer from calcium deficiency — unless they source it from other foods.

Categorizing foods between good and bad can also affect a person’s psychological views on food. A journal called Nutrition and the Brain was published and researchers found evidence that food deprivation can lead to food cravings.

Depriving oneself of certain foods can make a person have an unhealthy relationship with food — this can become a problem as they’ll be more at risk for developing an eating disorder when they overindulge. There’s the likelihood of them feeling guilty if they give in to their cravings.

Healthier Diet Alternatives

Keto and paleo were deemed as two of the unhealthiest diets (based on the American Heart Association’s ranking) because of how these diet plans can impact heart health. If improving your cardiovascular health is your number one concern, or you wish for healthier alternatives that AHA included in their ranking, here are other diets:

Tier 1:

DASH (Dietary Approaches to Stop Hypertension)

Diets high in fruits, vegetables, whole grains, nuts, legumes, lean meats, and poultry.

Mediterranean Diet

Diets high in fruits, vegetables, legumes, seeds, nuts, fatty fish, and occasional glasses of red wine.

Pescatarian and Vegetarian

Diets that are plant-based with the exception of fatty fish.

Tier 2:


A diet that’s strictly plant-based; without the consumption of animal products.

Low-fat Diet

Diets that limit the consumption of fats found in both animal and plant-based foods; reducing one’s overall caloric intake.

Tier 3:

Low-carb Diet

Diets that limit the consumption of carbs found in both animal and plant-based foods; reducing one’s overall caloric intake. (i.e. the South Beach Diet)

Tier 4:

Restrictive Diet

Diets that limit certain types of food or food groups; reducing one’s overall caloric intake. (i.e. Keto)


Diet fads can either work for you or not. Some of what many would find effective to them can be considered to be one of the unhealthiest diets by experts. If you’re planning to follow a weight loss program, make sure you get clearance from your physician — just to make sure that you don’t have an underlying disease that a diet program will exacerbate.

Weight loss is the only solution to prevent and fight obesity. But if you’re subjecting yourself to extreme diet methods, you’re not only endangering your physical health, but your mental well-being can also be affected if you develop an unhealthy relationship with food. Remember: all foods have nutritional value — they only become part of the unhealthiest diets if balance isn’t implemented.

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