10 possible adverse effects of the ketogenic diet

New low-calorie diet in vogue, it promises a quick weight loss. But as with any miracle solution, it may be too good to be true. Here, according to the specialists, are the main pitfalls of the ketogenic diet.


Sleeping troubles

The ketogenic diet is radically low in carbohydrates (carbohydrates) and very high in lipids: typically, 75% of calories come from fat, 20% from proteins, and only 5% from carbohydrates. This is an excessive disproportion, even in comparison to other severe diets. (The Paléo, for example, allows you to draw from 20 to 40% of your calories in carbohydrates).

By slashing carbohydrates to this point, the body is forced to enter ketosis, a state of metabolism where the body begins to break down fat quickly to serve as a fuel. This sounds good, but the effect is rather painful. During the first days – and sometimes weeks – of ketosis, you can feel tired, irritable, dizzy and sleep disturbed.

This craving for carbohydrates is often called “ketogenic flu,” says nutritionist and registered dietitian Dana Notte, director of nutrition at Green Mountain at Fox Run, a Vermont care facility known to help women “drop out” healthily. addiction to diets.


Muscle loss

Contrary to popular belief, the ketogenic diet is not a protein-rich diet. In fact, it involves slashing both carbohydrates and proteins. And according to the research, this protein deficit can pay a heavy price to your muscles. When you reduce the carbohydrates that come from fruits, vegetables and grains, Notte says, your body will begin to steal protein from muscles or other tissues to turn them into carbohydrates. “Proteins are used to form our organs, our heart, our muscles, as well as certain hormones, antibodies and neurotransmitters. “

Notte explains that if you lose weight so fast at the beginning of a ketogenic diet, it’s because you’re actually losing muscle, not just fat. This information, she adds, is often a revelation to her Green Mountain clientele, most of whom have spent years on yo-yo diets.


Foggy brain

When ketosis is at its peak, the body stops taking its fuel from the protein and starts burning fat. “The body starts to start fattening more fat,” says Notte. When the body metabolizes fat, molecules called ketones are released, and some brain cells can use them as a source of energy. However, according to the research, your brain needs more than 100 g of carbohydrates a day. And by the time the body makes the transition to use fat (ketones) as fuel, the brain can suffer.

People who make extremely low carbohydrate diets like the ketogenic often complain of a “brain fog”. “I remember in particular,” says Notte, “a client who had been on a ketogenic diet as a result of Polycystic Ovary Syndrome (PCOS). She kept telling me how much better she felt after one or two weeks of a more balanced and nutritious diet, thanks to our program. “


Dehydration and leg cramps

Another reason for rapid weight loss at the start of a ketogenic diet is that you lose water. “Nitrogen is one of the residues of the decomposition of proteins to produce energy,” explains Notte. “And the nitrogen that moves freely in the body is toxic, which is why it evacuates it by urges to urinate more frequently.” This elimination of fluids is reflected on the scale by lost pounds.

But it can also lead to dehydration and an imbalance of electrolytes – those minerals and salts that your muscles depend on. That’s why some ketogenic diet addicts have terrible leg cramps, says Notte. “The same problem arises with the Atkins diet, whose ketogenic is just an updated version.”


Increased stress

The ketogenic diet is very restrictive, surpassing even the Atkins and Paleo diets. A portion of fruit or steamed beetroot may cause you to exceed the allowable carbohydrate limit. “And restrictive diets cause psychological stress,” says psychotherapist Shiri Macri, a medical assistant and certified mental health counselor at Green Mountain at Fox Run, who specializes in working with people who “eat their emotions,” reacting to stress through stress. binge. “When you deprive the body of the amount of food or nutrients it needs, it responds by triggering a state of emergency. The levels of cortisol, the stress hormone, begin to rise, and serotonin, a mood regulator, will instead fall.


Loss of appetite control

This is a well-known phenomenon, whatever the type of diet or almost: the slightest snag to the rules, you will immediately start to overeat. Excluding entire food groups – including cereals, carbohydrates and other carbohydrates – makes them more attractive, says Macri, adding that this reaction is not only psychological but also physical.

“In the brain, serotonin is one of the chemicals of well-being. When it goes down – during a diet that drastically cuts carbohydrates, for example – the brain goes into a state of alert, waiting for a form of compensation, “she explains. Introduce some sugar and bread into this diet, and you may be overwhelmed by the urge to eat more, Macri warns. “The ketogenic only increases the possibility of being caught in a craving for these forbidden foods. “

Fragile bones

Ketones – these molecules produced during fat metabolism, triggered by the ketogenic diet or other diets very low in carbohydrates – are acidic. “When these substances begin to accumulate in the blood, it becomes more acidic,” explains Notte. One of the ways for the body to neutralize these high levels of acidity is to use a base, such as calcium. “And it’s in the bones that he’s going to get that alkaline mineral.”

In the long term, chronic calcium loss can lead to bone loss, osteoporosis, and fractures.



Since cereals, most fruits and many vegetables are excluded from the menu, your intestines will become lazy. “It’s really hard to have enough fiber with this type of food,” says Notte. “And a characteristic side effect is constipation. “

Not only is constipation uncomfortable, it is also a sign that your intestinal system is protesting. “As a whole, the ketogenic diet is low in fiber – and it’s damaging to the health of the intestines. “


Dietary disorder

“When you follow a restrictive diet, the impression of deprivation increases to the point where you finally let go, eat something that is not part of the plan, and even gorges yourself, with the shame and guilt that then, “Notte warned. “We tell ourselves, I made a sprain of the rules, so, as well eat everything. “

These occasional cravings can be transformed, for those who already have a predisposition, into a real eating disorder called compulsion hyperphagia, according to the National Eating Disorders Association (US National Association of Eating Disorders).


Recovery of lost weight, and even more

The ketogenic diet cuts through so many healthy foods and is so difficult to follow that even its most ardent advocates advise to adopt it only temporarily. The problem, says Macri, is that when you stop the diet, you take back the weight lost, with even a few more pounds.


If the ketogenic diet does not work, what else to try?

The temporary nature of the ketogenic diet and its significant side effects make it a more than an imperfect choice for most weight loss candidates, says Dr. Marcelo Campos, a Harvard Vanguard physician and senior lecturer at the Faculty of Medicine. Harvard.

According to Macri, “If you are looking for better physical and psychological health, the best way to do that is to use a holistic approach. This involves a balanced diet without being restrictive, moving regularly and examining the role of stress in one’s own life. Efforts in these three areas will not only improve health but boost morale! “