The harm and benefits of the keto diet, contraindications and possible health consequences

The ketogenic diet is currently at its peak, popularized by celebrities such as Kim Kardashian, Megan Fox, Riana and Matthew McConaughey. Before blindly believing in the PR of the next elixir of harmony, you need to figure out whether this method of being in good physical shape is so perfect, and what harm the keto diet can do to the body later.

is it ok to eat fish on a keto diet

In Search of the Perfect Diet

Until now, no such diet for weight loss has been found, in which there is a rapid burning of fat, there is no feeling of hunger, and the state of health is getting better and better every day. Every diet has its flaw, which is why there is someone describing the harm of another invented way to eat in order to lose weight.

So the ketogenic diet (in another way it is called a carbohydrate-free) has not only its supporters, but also opponents who are ready, on a scientific basis and the results of experimental research, to tell you why the keto diet is harmful and what to expect if you deprive the body of carbohydrate nutrition.

Ketosis is the basis of the popular diet

In a normal diet, carbohydrates are the main source of energy. After entering the body, as a result of several chemical reactions, they are converted into glucose, which is necessary for the functioning of the brain, central nervous system and other organs. The excess of the resulting glucose is placed in the glycogen depot. From there, it is removed as needed between meals. If these reserves are exhausted, then the energy is taken from the stored fats.

That is, in the normal state, carbohydrates are used by the body as a source of energy, and fats are stored. In the absence of carbohydrates, ketone bodies derived from fat cells are a backup source of nutrition.

In order for the body to enter such a state of metabolism, the amount of carbohydrates supplied with food for 3-4 days should not exceed 20 g per day. During this time, all glycogen stores will be depleted and the breakdown of fats will begin to obtain the necessary energy. That is, a process called ketosis will start.

Medical Applications

The essence of the ketogenic diet is that the main source of energy in the body - carbohydrates is reduced to a minimum, and the alternative - the breakdown of fats increases. This method of nutrition was originally used to treat patients with epilepsy and diabetes mellitus.

Currently, it is often prescribed in complex therapy for cancer patients, patients with Parkenson's or Alzheimer's disease, for the treatment of acne, since an excess of fast carbohydrates is one of the causes of the spread of acne.

Doctors still consider ketogen to be more useful for health improvement than for weight loss. When carbohydrates are burned, many free radicals are formed that attack and damage cells. When using fats, radicals harmful to the body are released much less.

What is allowed and what is not?

To understand the essence of nutrition and to understand for yourself whether the keto diet is harmful to health or not, you need to get to know it better, find out the menu, diet, nutritional rules and contraindications.

The menu should be based on the main principle - the exclusion of carbohydrates from the diet. Therefore, you can eat any food you want. Only on one condition: that they do not contain any carbohydrates, whether fast or slow.

Also, when drawing up the menu, it is necessary to observe the main rule of any diet for weight loss: the number of incoming calories per day should be less than the amount consumed over the same period.

If these two main rules are observed, then you can expect results for weight loss, fats will begin to burn when ketosis occurs. All that remains is to draw up a keto diet menu, which, if possible, will take into account all the pros and cons.

what foods can and cannot be eaten on a keto diet

Prohibited Products

Based on the basic principle of the ketogenic diet, you should exclude from the diet:

  • all flour products - pasta, confectionery, baked goods;
  • sweets - sweets, jams;
  • any sweet drinks;
  • fruits;
  • vegetables with a high starch content - potatoes, corn, legumes;
  • cereals - semolina, oatmeal, rice, and others.

It will be hard for those with a sweet tooth. But they must decide for themselves which is more important: the taste of chocolate candy and favorite strawberry jam or the feeling of a slim, beautiful body.

Approved Products

The keto diet includes all foods that do not contain carbohydrates, do not raise blood sugar levels, and prevent the body from stopping the fat burning process. This:

  • meat, fish, seafood in any form;
  • fresh and sour milk without fillers or sweeteners;
  • eggs without limits;
  • vegetable oils;
  • green vegetables, lettuce;
  • tomatoes, pumpkin, avocado;
  • mushrooms;
  • some nuts and berries of any kind;
  • coffee, tea without sugar, unsweetened mineral water.

Milk should be limited in quantity as it contains milk sugar. Saturated fats in meat and dairy products should not exceed 13 g per day. And vegetable oil, avocados and nuts should be present in the diet every day. It is these products that are considered the basis in the famous Mediterranean diet. Considering that 1 medium-sized apple contains 20 g of sugar, you can allow half of the fruit to be eaten for an afternoon snack.

Looking at the list of what is allowed on the keto diet, you can create a menu. Below is an example of meals for 1 day. Already from it you can understand that the body will not wait for energy help from food.


  • natural yogurt - 100 g;
  • cottage cheese - 100 g;
  • berries - 30 g;
  • olive oil - 20 g;
  • coffee - 200 ml.


  • chicken fillet - 80 g;
  • green beans - 100 g;
  • vegetable oil - 25 g;
  • tomatoes - 60 g;
  • green tea - 200 ml.


  • cheese - 20 g;
  • avocado - 50 g;
  • nuts - 20 g;
  • mineral water - 200 ml.


  • fish - 80 g;
  • cabbage salad - 100 g;
  • olive oil - 25 g.

Before bed, you can drink a glass of kefir or natural liquid yogurt. Ketogenic nutrition suppresses the production of the hormone ghrelin, which is responsible for feeling hungry. Therefore, a properly selected menu will allow you to spend time on a diet without an acute feeling of hunger and a constant desire for something to eat.

What rules need to be followed?

In order to prevent the dangers of the keto diet from causing great damage to the body, it is recommended to first prepare the body by gradually removing carbohydrates from your diet. First of all, you need to reduce the use of sweet and starchy foods. You should study which foods are fast carbohydrates, completely abandon them, cutting their diet by about 20% every day. In parallel, you should increase the amount of healthy fats.

After getting ready, you can switch to keto. At the beginning of the diet, the composition of the consumed food should be in a certain ratio of fats, proteins and carbohydrates: 60%, 30% and 10% of the daily calorie intake.

In order to start the process of breaking down fats, the level of glucose in the blood must drop to minimum values and hold out in this amount for 2 days. This alone will help the body start using fat as an energy source.

How is the adaptation of the organism going?

At the very beginning of ketogenics, due to a lack of insulin in the blood, unpleasant sensations may appear that not everyone can easily endure. You need to know about them in order to be ready and not afraid. This:

  • dizziness;
  • weakness;
  • nausea;
  • bad breath;
  • decreased physical activity.

These side effects are called the keto flu. To soften the body's response to dietary changes, it is recommended to drink plenty of water, as well as add potassium, magnesium and sodium supplements to your diet.

Several well-known diets are inherently ketogenic. For example, protein, low carbohydrate, no carbohydrate. In them, the main principle is to reduce the amount of consumed carbohydrates before the onset of ketosis.

foods to help the body adapt to the keto diet

Who is prohibited from the keto diet?

The state of ketosis is not entirely natural for the body. It is included in the work as a backup option only when there is no habitual diet, that is, if suddenly there is a hunger. As you know, hunger is not always useful, and for a certain category of people, it is even dangerous, since it does not provide the body with the elements it needs.

Especially careful should be those for whom the ketogenic diet has contraindications. And this:

  • pregnant women;
  • diabetics;
  • people with chronic liver and kidney diseases;
  • having a disorder in the immune system;
  • those who consume alcohol and use anabolic sports supplements.

In addition, this type of diet requires a lot of water to avoid toxicosis. And this may be unacceptable for some diseases.

What achievements can you achieve?

To understand if the keto diet is worth considering, you need to know about the pros and cons that it can lead to. In addition to losing 5 kg of weight per month and a feeling of lightness throughout the body, the plus is that you can remove the dependence on sweets and make a balanced diet for later life.

The benefits of starch-free vegetables will be appreciated. These are: asparagus, broccoli, spinach. These foods are rich in dietary fiber, which is beneficial for the intestines. They are low in calories and can be eaten in large quantities.

Why is the keto diet dangerous?

The ketogenic diet involves a dramatic change in the way you eat. This means that the body will receive a certain amount of stress and may not react positively. The main harm of the ketone diet may not be due to the lack of carbohydrates. The brain is able to function normally on ketone bodies. The state of the body will be deplorably affected by a diet poor in vitamins and other important elements.

Before deciding to switch to this type of diet, you should be aware of the possible consequences. It is on them that opponents of the ketogenic diet focus. Here are the main cons of the keto diet:

  1. Being in ketosis causes high levels of methionine, glutamine, asparagine and other amino acids that cancer cells depend on. Consequently, the risk of developing cancer is increased.
  2. Increased consumption of animal fats leads to an increase in cholesterol plaques on the walls of blood vessels, the formation of atherosclerosis and problems with the cardiovascular system.
  3. The exclusion of fruits and a large number of vegetables from the menu leads to the fact that a prolonged lack of fiber contributes to the appearance of constipation and disruption of the gastrointestinal tract. And the deficiency of essential vitamins and minerals negatively affects the general condition.
  4. The body loses the habit of processing carbohydrates and even a small intake of glucose can cause a sharp jump in blood sugar levels. This can trigger diabetes.
  5. With prolonged ketone nutrition (more than 1. 5 months), the level of ammonia in the blood rises, and this leads to general intoxication of the body and disruption of hormonal balance.
  6. There is an unpleasant odor of acetone from the mouth, body and urine.
  7. Weakness, dizziness appear, efficiency decreases, concentration of attention worsens. All this significantly reduces the quality of life both at work and at home.

Scientific studies have shown that, in addition to raising ammonia in the blood, the amount of bad cholesterol increases due to the increased consumption of animal fats. Since the amount of protein in the diet is small, muscular dystrophy gradually sets in, and kidney stones form.

It can be concluded that the keto diet is only suitable for completely healthy people without any health problems and confident that they can survive without carbohydrates for 6-8 weeks.

The Effects of the Keto Diet

In recent years, scientific organizations have conducted many controlled studies on which diet is most beneficial and which is harmful. This was done for the purpose of commercial offer to potential buyers of healthy food products.

Here's what the data has been collected and published on the health benefits of the keto diet:

  1. People who follow a low-carb diet have a shorter life expectancy than those who have unlimited slow carbs in their diet.
  2. Those who exclude vegetables and fruits from their diet are 32% more susceptible to various diseases compared to those who consume them in sufficient quantities.
  3. A comparison of low-carb versus low-fat diets in overweight people has shown that cutting fat on the menu is more effective than cutting carbs.
  4. Also compared the results of the keto diet with the results obtained from a diet high in slow carbohydrates at the same calorie content. A diet high in sugars has resulted in more weight loss than a ketogenic diet in the same amount of time.

This conclusion is not in favor of a low-carb keto diet. Apparently, a stressful state activates the body to overcome a negative situation and does not allow one to calmly part with an alternative source of nutrition.

zucchini noodles for the keto diet

Cyclic Diet

The keto diet, especially long-term, is not suitable for people who need to be active or have daily physical activity. These people include athletes. In the absence of the required amount of carbohydrates, the muscles will not be able to perform strength exercises.

But athletes are very enthusiastic and motivated people who are used to getting their way. Therefore, they found a suitable solution to get the benefits of the keto diet and reduce the possible harm. They began to use the so-called interval or cyclic diet. She combines ketone and carbohydrate, alternating them day by day. From Monday to Thursday evening, the athlete eats ketone, then fills the body with calories using carbohydrate foods until Sunday. Eats on Sunday by reducing carbohydrates and introducing healthy fats into the diet. This type of diet allows you to burn fat and at the same time build muscle mass, making your muscles bumpy.

Doctors do not recommend sticking to the keto diet for long. In order not to harm the body, it is recommended to do 1 fasting day a week. On this day, the body can be fed with carbohydrates.

Is control mandatory?

Before starting a keto diet, you need to visit a doctor to decide with him whether this method of eating will bring harm or benefit to the body. To do this, it is necessary to donate blood and urine for a general analysis, biochemistry, for sugar and insulin content. Long-term ketogenic nutrition (more than 2 weeks) is required under medical supervision. And when unpleasant symptoms appear, you need to contact him for advice.

How to safely enter ketosis?

It has been proven that the state of ketosis, when the body is on carbohydrate starvation and begins to burn its own fat stores, is very beneficial. This state can be achieved without the use of a ketogenic diet. You just need to go on a water hunger strike for 3-4 days.

As a result, autophagy occurs in the body, and the cells begin to self-purify, stem cells are activated, and the immune system regenerates. Such short-term fasting must be carried out periodically in order to cleanse the body and its self-healing.

A long-term keto diet has many disadvantages, the consequences of which are far from being investigated. The mere fact that a carbohydrate-free state is unnatural for the body should make one think before going on such a diet.