The ketogenic diet is a diet rich in lipids that have become incredibly fashionable in recent years. However, it has been used for nearly a hundred years to treat specific pathologies, including epilepsy. This diet aims to considerably reduce the consumption of carbohydrates in favor of lipids to cause a ketosis state. Beyond significant weight loss, it would have many health benefits.
What Is the Ketogenic Diet?
Although it has been in the spotlight for a short time, ketogenic dieting has been around since the early 1920s. This strict feeding protocol was developed for exceptional pathological cases, for example, when people had severe epilepsy. Today, however, this type of diet is used for many reasons, such as Alzheimer’s or cancer therapy. It is also prevalent among athletes and to promote weight loss.
The ketogenic diet is based on a high intake of fats (lipids), medium protein, and very low carbohydrates. There are many “types” of keto diets, from strict to flexible. On average, lipids’ ratio: proteins to carbohydrates is 4:1, i.e., about 80% of the energy consumed comes from fats while 15-20% comes from proteins and only less than 10% comes from carbohydrates (even 5% for a strict diet).
Thus, for a diet of 2000 calories per day, 1600 calories should come from fat, 300 to 400 calories from protein, and 100 to 200 calories from carbohydrates. If we consider that 1 g of fat is worth nine calories and 1 g of protein or carbohydrates is worth four calories, a person on a ketogenic diet could eat only 25 to 50 g of carbohydrates per day for 75-100 g of protein and 178 g of fat. Just for comparison, one apple contains an average of 20 g of carbohydrates!
Characteristics of The Ketogenic Diet
- Very high-fat consumption (75% of intake)
- 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 (renewed energy, protection against specific pathologies, etc.).
The Main Principles of The Diet
Initially used in children with epilepsy to reduce seizures, the Keto diet was developed in the 1920s. This diet first demonstrated anticonvulsant effects in people with epilepsy. Then, the Keto diet has gained popularity in recent years as a quick method for weight loss. It is also used to improve the symptoms of type 2 diabetes and cardiovascular disease.
How Does the Ketogenic Diet Work?
The ketogenic diet for weight loss is characterized by the consumption of:
50 g of carbohydrates maximum per day. This represents about 5% of the total calories consumed during the day. A regular diet usually provides between 45 and 65% of our calories in the form of carbohydrates.
This food thus completely reverses our traditional food pyramid and its great principles.
How Does the Ketogenic Diet Lead to Weight Loss?
Usually, the body gets its energy from the carbohydrates consumed during the day, which are necessary for the body to function correctly. In the ketogenic diet, because carbohydrates are minimal, the body begins to draw on its carbohydrate reserves stored in the muscles and liver called “glycogen” accounts. Since each gram of glycogen is bound to 3-4 grams of water in the body, the significant weight loss at the beginning of the ketogenic diet is mostly a loss of water.
When glycogen stores are depleted, the body naturally begins to use the lipids or fats to produce energy. However, when the body uses grease in the absence of carbohydrates, it has waste products called ketones. Then, ketones begin to accumulate in the blood and their smell, similar to nail polish, becomes noticeable on the breath. This is the leading indicator that the body is in a state of “ketosis.” It usually takes 2 to 4 weeks to reach this state. Ketosis” can be checked by buying urine test strips at a pharmacy.
This “ketosis” state causes a marked decrease in appetite, which reduces the amount of food eaten. It can also lead to nausea and fatigue. Although this diet does not focus on counting calories, those who follow it absorb fewer calories because they are not hungry, leading to weight loss.
How Long Does the Ketogenic Diet Last?
The ketogenic diet specific to weight loss has no time limit. It is more a lifestyle than a fixed-term diet. When practiced in the therapeutic field, the ketogenic diet has a variable duration from a few weeks to several years, depending on the expected results.
Foods Allowed in The Ketogenic Diet
Foods permitted in significant amounts in the ketogenic diet are :
- Vegetable oils
- Lemon juice
- Low-carbohydrate vegetables (spinach, lettuce, kale, etc.)
- Hard cheese (100 g per day)
The authorized foods, but to be consumed in moderation, are :
- Whole milk
- Whole milk yogurts
- Higher carbohydrate vegetables (except carrot, beet, sweet potato, pea, and corn)
- Strong alcohol
- Coffee without sugar
Since a large amount of fat is ingested every day, it is essential to be concerned about 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 primary sources of omega-6 are soybean, corn, safflower, grape seed, sunflower, and wheat germ oils. Therefore, it is necessary to limit the consumption of salad dressings, vinaigrettes, and mayonnaises made with these oils.
Consumption of monounsaturated fats (olive oil, avocado, nuts) and saturated fats (fatty cuts of meat, high-fat dairy products) is more recommended. The use of coconut oil is recommended because it contains fats that are easily transformed into ketones. Finally, the consumption of Omega-3 contained in fatty fish, rapeseed and linseed oil, nuts or chia, flax or hemp seeds should be sufficient.
The ketogenic diet is relatively restrictive; many foods are prohibited because they prevent the body from maintaining a ketosis state:
- Sweet products
- Viennese pastries
- Fruits (except berries)
- Sweet vegetables (beet, corn, carrot, etc.)
- Soft cheese
- fresh cheese
- Soft drinks
- Honey, jams, syrup
- Fruit and vegetable juices
- Sweet sauces
- Milk or yogurt-based on vegetable kinds of milk (soy, almonds, etc.)
- Flavored yogurts
- Sweet fruit compotes
What to Eat in The Ketogenic Diet? Typical Day’s Menu
Omelet with two eggs and ½ cup of spinach and mushrooms
100 g of rhubarb compote.
Roast beef (150 g)
Green salad (100g) and grated red cabbage (50g)
Five black olives
Vinaigrette (2 to 3 tablespoons)
Snack: cucumber (50g) and gouda (40g)
Salmon (200 g)
Green salad (50g)
Vinaigrette (1 to 2 tablespoons)
Hard cheese (40g)
1/4 cup almonds
Advantages and Disadvantages
The Positive Points of The Ketogenic Diet
- Feeling of satiety
- No calorie restriction
- An adequate intake of quality lipids and proteins
- Rapid weight loss
- Potentially positive effect on blood lipid levels
The Negative Points of The Keto Diet
- Unpleasant side effects in the first weeks (ketogenic flu)
- Little dietary diversity
- No deviation allowed
- Difficult to follow
- 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. This is a transitional period that almost always accompanies the body’s passage into a state of ketosis. Beware, some side effects seem to persist even after the transition period, such as hypoglycemia (low blood sugar), dehydration, as well as an increased risk of urinary lithiasis 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 products, excellent sources of fiber and micro-nutrients.
Cancer, Epilepsy: What Are the Therapeutic Indications of The Ketogenic Diet?
Beyond weight loss, the ketogenic diet is used to treat various pathologies: epilepsy, cancers, inflammatory diseases, etc. In the therapeutic field, the interest in the ketogenic diet is no longer to be proven.
Is This Diet Compatible with Weight Training and Sports?
Yes, absolutely. Some studies even demonstrate the benefits of the ketogenic diet, which would allow for better performance, reduce recovery time, and facilitate the effort. For the past few years, this diet has been trendy in the sports world.
How Can You Avoid Gaining Weight?
The ketogenic diet is more of a lifestyle than a limited-time diet. It is, therefore, not supposed to be abandoned after a few months. However, given the very significant restrictions it creates, it seems inevitable to regain weight if it were to be stopped. To avoid too great a yo-yo effect, it would seem beneficial to be accompanied by a nutrition professional who could gradually reintroduce carbohydrates into the diet without too many consequences.
How Do I Know if I Have Ketosis?
Commonly, ketosis occurs within a few days, 72 hours for most people. Some signs are easily seen. First of all, there is the smell. Indeed, the release of ketones results in bad breath. Don’t worry; there are many tricks to camouflage it. Then, you will quickly notice a decrease in appetite. Also, physical symptoms may be experienced during the first few days. Some people will experience nausea, cramps, fatigue, or dehydration. Fortunately, these discomforts usually last only two or three days while the body gets used to its new diet.
After a few days, you will fall into a state of ketosis. However, it may take one to two months for the body to use only fat as an energy source. This stage is called keto-adaptation.
To properly follow the Keto lifestyle, it is recommended to measure your ketosis level. Two techniques currently exist on the market. There are urine strips and blood glucose meters. The first is easier to use but is less accurate. The second is more expensive and determines the exact concentration of ketones in the blood.
A Few Figures to Go Further
As the ketogenic diet is very high in fat, many concerns remain about its potential negative impact on cardiovascular risk. However, according to a recent study conducted in 2013, the ketogenic diet results in more significant weight loss than a low-fat diet, but it also has a positive impact on blood pressure, HDL (good) cholesterol levels, and blood triglycerides. It has also been shown that the ketogenic diet can lead to increased levels of LDL (bad) cholesterol. This is because saturated fats are not as harmful as people think. These new data are still recent but still need to be taken into consideration.
In terms of weight loss, the ketogenic diet is more effective than a low-fat diet. Indeed, many studies have compared low-fat or high-protein, medium-carbohydrate diets to the ketogenic diet. The results show that the ketogenic diet is more effective in weight loss in the short term (1 year and less). On the other hand, very few studies have evaluated this diet’s effects 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. The withdrawal of cereal products, legumes, and fruits can lead to certain deficiencies, particularly in fiber, vitamins, and antioxidants, which play many health roles. However, it is difficult to deny the proven positive effects of this diet on health. Although 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 a little more clearly in the years to come.
The Ketogenic Diet and It’s Functioning: Our Conclusion
The ketogenic diet is the most extreme form of low carb dieting and can lead to weight loss.
Foods high in fat such as salmon, avocado, nuts, or eggs should be featured in your keto diet. Foods rich in saturated fatty acids (delicatessen, cheese) can also be eaten, but on a smaller scale.
Even with a limited intake of carbohydrates, try to vary the dishes as much as possible. It is essential to maintain a varied and healthy diet.
Many vegetables and fruits are not suitable for the keto diet. Therefore, we advise you to prepare a relatively exhaustive list of foods allowed in the keto diet so that you always have a daily intake of fruits and vegetables.