The ketogenic diet (keto diet) contains approximately 90-99% of calories from fat and protein and only 1-10% from carbohydrates.Eating this way may provide some benefits for weight loss or reducing the number of epileptic seizures.
However, as a new study has found, following the keto diet only provides health benefits for a short period of time - 1-2 weeks - after which its negative effects begin to occur.
What is the keto diet?
The ketogenic diet (or keto diet for short) is a very low-carb, high-fat diet that may have some health benefits.
More than 20 studies have shown that this type of diet can help you lose weight and improve your health.Ketogenic diets may even have some benefit for diabetes, brain cancer, epilepsy and Alzheimer's disease.
The ketogenic diet is a very low-carb (no more than 1-10%), high-fat diet that has many similarities to the Atkins diet and low-carb diet.Following this diet leads to a sharp reduction in carbohydrates and replacing them with fats and protein.This greatly reduces the body's use of carbohydrates and switches the body to using fat as its main source of energy.If there is little glucose in the body, the liver processes fat into fatty acids and ketone bodies.
When the amount of ketone bodies in the body increases, ketosis occurs, and the brain begins to use these ketone bodies instead of carbohydrates.When this happens, the body becomes incredibly efficient at burning fat for energy.
The ketogenic diet can significantly reduce blood glucose and insulin levels.This, coupled with the increased amount of ketones, shows some beneficial benefits for the body.
However, the keto diet can be potentially dangerous for people with type 1 diabetes.
Benefits of the keto diet
One study of 63 people created two groups: either a low-fat diet group or a low-carbohydrate diet group.The group of people with a low-fat diet was limited in calories.This study continued for 12 months.
The low-carb group lost more weight, 7.3% of their total body weight, compared to the low-fat group, which lost 4.5%.The difference was statistically significant at 3 and 6 months, but not at 12 months.At the end of the experiment, there was no difference in weight between the groups of people.
It's worth noting that the low-carb (keto diet) group had elevated blood levels of triglycerides and HDL, but other biomarkers were similar between groups.
If we analyze the known 23 clinical studies on humans assessing the effect of low-carbohydrate diets (keto diets), we can formulate the general conclusions of these studies.Most studies achieved statistically significant differences in weight loss (always in favor of low-carbohydrate diets).
There are a few other factors worth noting:
- Low-carb diets often resulted in 2-3 times more weight loss than low-fat diets.In some cases there was no significant difference.
- In most cases, calories were restricted in the low-fat groups, while the low-carb groups were able to eat as much as they wanted.
- When all groups of subjects restricted calories, the low-carb diets still showed greater reductions in body weight, although this was not always significant.
- There was only one study in which the low-fat diet group lost more weight, although the difference was small (0.5 kg) and not statistically significant.
- In some studies, weight loss was greatest early on.People then begin to regain the weight over time and after they come off the keto diet.
- When scientists looked at the amount of abdominal fat (bad visceral fat), low-carb diets had a clear advantage in reducing this type of fat.
Two of the main reasons low-carb diets (keto diets) are so effective for weight loss are the high protein content of the food and the appetite-suppressing effects of this style of eating.This results in a dramatic reduction in calorie intake.
Harmful effects of the keto diet
Clinical studies indicate that the keto diet can improve a person's health over a short period of time (up to 12 months) by reducing the risk of developing type 2 diabetes and, as a result, reducing inflammation caused by fat cells.
A study conducted at Yale University found that the positive and negative effects of diet are related to the behavior of immune cells called gamma delta T cells (γδ T cells), tissue-specific cells that reduce the risk of diabetes and inflammation.
Gamma delta T cells are immune T cells that have the distinctive T cell receptor (TCR) on their surface.Most T cells are αβ (alpha beta) T cells with a TCR consisting of two glycoprotein chains called the α (alpha) and β (beta) TCR chains.In contrast, gamma delta (γδ) T cells have a TCR that consists of one γ (gamma) chain and one δ (delta) chain.This group of T cells tends to be less abundant—about 4–10% of all T cells—than αβ T cells, but have the highest abundance in the intestinal mucosa, within a population of lymphocytes known as intraepithelial lymphocytes (IELs).
Gamma-delta immune T cells are characterized by a number of characteristics that place them within the boundaries of the more evolutionarily primitive innate immune system, which provides a rapid response to a variety of pathogens, and the adaptive immune system, where lymphocytes coordinate their actions much more slowly.At the same time, (γδ) T cells have the ability to have long-term memory in order to respond even more quickly to pathogens when they are encountered again in the future.
Keto diet leads to increased presence of immune (γδ) T cells and depletion of them in adipose tissue
The keto diet tricks the body into burning fat, said study author Dr. Vishwa Deep Dixit of the Yale School of Medicine.When the body's glucose levels decrease due to low carbohydrate content in food, the body behaves as if it is in a fasted state, even though it is not, and begins to burn fats instead of carbohydrates.
This causes the body to use β-hydroxybutyrate (beta-hydroxybutyric acid) to produce ATP and reduces inflammation mediated by NLRP3, a cytosolic protein involved in the activation of the inflammatory interleukins IL-1b and IL-18.
The process of reducing carbohydrates in food, in turn, begins to produce ketone bodies (ketones) as an alternative source of fuel.When the body burns ketone bodies, protective gamma delta T cells spread throughout the body.And the number of these protective immune cells in adipose tissue decreases sharply.As γδ T cells in adipose tissue decrease, the level of inflammation that these cells previously contained begins to increase.Inflammation is known to stimulate the accumulation of fat cells.
Moreover, mice that lacked immune γδ T cells showed impaired glucose homeostasis, leading to increased glucose levels in the blood.
The keto diet reduces the risk of diabetes and inflammation, and also improves the body's metabolism, the scientists noted.After a week on the keto diet, mice showed reduced blood sugar and inflammation.
But when the body is in this “hunger-not-hunger” mode for a long enough time (more than 1-2 weeks), fat accumulation occurs simultaneously with its breakdown, scientists have found.When the mice continued to eat a high-fat, low-carbohydrate diet, they consumed more fat than their bodies could burn.And then the signs of diabetes and obesity began to increase.
Side effects of the keto diet
Although the ketogenic diet is safe for healthy people, there may be some initial side effects while your body adjusts to the new diet.
This presentation is often called the keto flu and usually ends within a few days.Keto flu includes low body energy and impaired mental function, increased hunger, sleep problems, nausea, digestive discomfort and decreased performance during exercise.
To minimize this, you can start on a low-carb diet for the first few weeks.This can train your body to burn more fat before you completely eliminate carbohydrates from your diet.
The keto diet can also change your body's water and mineral balance, so adding extra salt to your meals or taking a mineral supplement may help.Try taking 3,000-4,000 mg sodium (salt), 1,000 mg potassium and 300 mg magnesium per day to reduce side effects.