Keto diet advantages and disadvantages

The ketogenic diet has been a high fat diet that has been particularly popular in recent years. However, it has been used for nearly a hundred years to treat certain pathologies, including epilepsy. This diet aims to dramatically reduce carbohydrate intake in favor of fat to induce a state of ketosis. Beyond the significant weight loss, it is said to have many health benefits.



Features of the ketogenic diet:

  • Very high consumption of lipids (75% of intakes)
  • Unchanged protein intake
  • Considerable reduction in carbohydrate intake
  • Causes unpleasant symptoms in the first few weeks (ketogenic flu)
  • Rapid weight loss
  • The state of ketosis would have many health benefits (energy boost, protection against certain pathologies, etc.)
keto diet

The main principles of the regime

Originally used in children with epilepsy to reduce seizures, the ketogenic or keto diet was developed in the 1920s. This diet was first shown to have anticonvulsant effects in epileptics. Then, the keto diet has gained popularity in recent years as a quick method to lose weight. It is also used to improve symptoms of type 2 diabetes and cardiovascular disease.

How does the ketogenic diet work?

The ketogenic diet for weight loss is characterized by consuming:

  • 50 g of carbohydrates maximum per day. This represents about 5% of the total calories consumed during the day. A normal diet usually provides 45-65% of our calories as carbohydrates.
  • 75% fat
  • 20% protein


This food therefore completely reverses our traditional food pyramid and its main principles.

How does the ketogenic diet lead to weight loss?

Usually, the body gets its energy from the carbohydrates consumed during the day and which are necessary for the proper functioning of the body. In the ketogenic diet, نظام الكيتو

because carbohydrates are extremely limited, the body begins to draw on its stores of carbohydrates stored in the muscles and liver called stores of "glycogen". Since every gram of glycogen is bound to 3-4g of water in the body, the significant weight loss at the start of the ketogenic diet is largely water loss. When glycogen stores are depleted, the body naturally begins to use lipids or fat for energy. However, when the body uses fat in the absence of carbohydrates, it produces waste products called ketones. Then, Ketones start to build up in the blood and their smell, similar to nail polish, becomes noticeable on the breath. It is the main indicator that the body is in a state of "ketosis". It usually takes 2-4 weeks to get to this state. You can check for "ketosis" by purchasing urine test strips at a drugstore.


This state of "ketosis" causes a marked decrease in appetite which helps reduce the amount of food eaten. This condition can also lead to nausea and fatigue. Although this diet does not focus on calorie counting, those who follow it actually take in fewer calories because they are not hungry and this leads to weight loss.

How long does the ketogenic diet last?

The specific ketogenic weight loss diet has no time limit. it's more of a lifestyle than a fixed-term diet. When practiced in the therapeutic field, the ketogenic diet has a duration varying from a few weeks to several years depending on the desired results.

Foods Allowed on the Ketogenic Diet

Foods permitted in significant amounts in the ketogenic diet are:


Authorized foods, but to be consumed in moderation, are:

  • Whole milk
  • Whole milk yogurts
  • Vegetables higher in carbohydrates (except carrots, beets, sweet potatoes, peas and corn)
  • Wine
  • Strong alcohol
  • Coffee without sugar

Since a large amount of fat is ingested each day, it is important to be aware of the type of fat consumed. It is advisable to limit the consumption of omega-6 fatty acids which in excess have a pro-inflammatory effect. The main sources of omega-6 are soybean, corn, safflower, grape seed, sunflower and wheat germ oils. We must therefore limit the consumption of salad dressings, vinaigrettes and mayonnaise made with these oils.

Consumption of monounsaturated fat (olive oil, avocado, nuts) and saturated fat (fatty cuts of meat, high fat dairy products) is more recommended. The use of coconut oil is recommended because it contains fats which are easily converted into ketones. Finally, the consumption of Omega-3 contained in oily fish, rapeseed and flaxseed oil, walnuts or even chia, flax or hemp seeds must be sufficient.

Prohibited foods in keto diet

The ketogenic diet is relatively restrictive, many foods are prohibited in it because they prevent the body from maintaining itself in a state of ketosis:

  • Sugar
  • Sweet products
  • Cereals
  • Starchy
  • Bread
  • Pastries
  • Pastries
  • Biscuits
  • Legumes
  • Fruits (except berries)
  • Potato
  • Sweet vegetables (beets, corn, carrots, etc.)
  • Soft-paste cheese
  • cream cheese
  • Soft drinks
  • Chocolate
  • Honey, jams, syrup
  • Fruit and vegetable juices
  • Sweet sauces
  • Milk or yoghurt made from vegetable milks (soya, almonds, etc.)
  • Flavored yogurts
  • Sweet fruit compotes

What to eat on the ketogenic diet? Typical one-day menu


Omelet with 2 eggs and ½ cup spinach and mushrooms                                   
100 g rhubarb compote


Roast beef (150 g)
Green salad (100g) and grated red cabbage (50g)
5 black olives
Vinaigrette (2 to 3 tbsp)
Snack: cucumber (50g) and gouda (40g)


Salmon (200 g)
Asparagus (100g)
Green salad (50g)
Vinaigrette (1 to 2 tbsp)
1/2 avocado
Hard cheese (40g)


1/4 cup almonds

Advantages and disadvantages

The positives of the ketogenic diet

  • Feeling full
  • No calorie restriction
  • Good supply of quality lipids and proteins
  • Rapid weight loss
  • Potentially positive effect on blood lipid levels

The negatives of the keto diet

  • Unpleasant side effects in the first few weeks (ketogenic flu)
  • Little dietary diversity
  • No deviation allowed
  • Difficult to follow
  • Monotone
  • Not very compatible with a fulfilling social life

Recommendations and precautions to be taken

What are the dangers of the ketogenic diet?

In the first few weeks, very unpleasant effects can occur. We are talking about the ketogenic flu. it is a transitional period almost systematically accompanying the passage of the organism into a state of ketosis. Be careful, some side effects seem to persist even after the transition period such as hypoglycemia (low blood sugar level), dehydration as well as an increased risk of urolithiasis or kidney stones and constipation. A fiber and vitamin supplement is recommended when following this diet, probably due to the low content of fruits, legumes and whole grain cereal products which are very good sources of fiber and micronutrients.

Cancer, epilepsy: what are the therapeutic indications of the ketogenic diet?

Beyond weight loss, the ketogenic diet is used in the treatment of various pathologies: epilepsy, cancers, inflammatory diseases, etc. This is why it was originally created in the 1920s. In the therapeutic world, the interest of the ketogenic diet is well established.

Is it a diet compatible with bodybuilding and sport?

Yes quite. Some studies even demonstrate the benefits of the ketogenic diet which would allow better performance, reduced recovery time and which would facilitate exertion. In recent years, this diet has been very popular in sports.

How not to gain weight?

The ketogenic diet is more of a lifestyle than a time-limited diet. So it is not supposed to be abandoned after a few months. However, given the very large restrictions it entails, it seems inevitable that gaining weight again should it be stopped. To avoid a too strong yo-yo effect, it would seem beneficial to be accompanied by a nutrition professional who could help gradually reintroduce carbohydrates in the diet without this having too heavy consequences.



Some figures to go further

As the ketogenic diet is very high in fat, many concerns persist about its potential negative impact on cardiovascular risk. However, according to a recent study conducted in 2013, not only does the ketogenic diet lead to greater weight loss than a low-fat diet, but it would also have a positive impact on blood pressure, HDL cholesterol levels (good cholesterol) and blood triglycerides. The ketogenic diet has also been shown to cause elevation in LDL (bad) cholesterol levels. This is because saturated fat is not as bad as you think. These new data remain recent but still need to be taken into consideration.

In terms of weight loss, the ketogenic diet has been shown to be more effective than a low fat diet. Indeed, many studies have compared diets low in fat or high in protein and moderately high in carbohydrates with the ketogenic diet. The results show that in the short term (1 year and less), the ketogenic diet is more effective on weight loss. On the other hand, very few studies have evaluated the effects of this diet in the longer term.

Dietitian's Opinion on the Ketogenic Diet

This diet frankly does not respect the basic rules of a balanced diet. It excludes many food groups and seems to forget the notion of pleasure. Withdrawing from cereal products, legumes and fruits can lead to certain deficiencies, particularly in fibers, vitamins and antioxidants which play a number of roles in health. However, it is difficult to deny the proven positive effects that this diet seems to have on health. If it is difficult to recommend it for the moment because of its very restrictive nature, many studies in progress should make it possible to see it a little more clearly in the years to come.