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 in terms of weight loss or reducing the number of seizures.
However, as a new study found, following the keto diet only provides health benefits for a short period of time – 1 to 2 weeks – after which its negative effects begin to show.
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 beneficial effects on diabetes, brain cancer, epilepsy and Alzheimer's disease.
The ketogenic diet is a diet that is very low in carbohydrates (no more than 1-10%), high in fat and has many similarities to the Atkins diet and the low-carb diet.Following this diet involves a sharp reduction in carbohydrates and their replacement with fats and proteins.This significantly reduces the body's use of carbohydrates and causes the body to use fat as its primary source of energy.If there is little glucose in the body, the liver converts fats 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 sugar and insulin levels.This, coupled with the increased amount of ketones, has beneficial benefits for the body.
However, the keto diet can be potentially dangerous for people with type 1 diabetes.
Benefits of the keto diet
A study of 63 people created two groups: either a group on a low-fat diet or a group on a low-carb diet.The group of people on a low-fat diet was restricted 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, who 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.
Of note, the low-carb group (keto diet) had elevated blood levels of triglycerides and HDL, but other biomarkers were similar between the groups.
If we analyze the 23 known human clinical studies evaluating the effect of low-carbohydrate diets (keto diets), we can formulate the general conclusions of these studies.Most studies found statistically significant differences in weight loss (always favoring low-carb diets).
There are a few other factors to note:
- Low-carb diets often result 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 could eat as much as they wanted.
- When all subject groups restricted their calories, the low-carb diets still showed greater weight reductions, 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 greater early on.People then begin to regain weight over time and after stopping 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 why low-carb diets (keto diets) are so effective for weight loss are the high protein content of the foods and the appetite-suppressing effects of this eating style.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, therefore, reducing inflammation caused by fat cells.
A study at Yale University found that the positive and negative effects of diet are linked 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 composed of one γ (gamma) chain and one δ (delta) chain.This group of T cells tends to be less abundant (approximately 4–10% of all T cells) than αβ T cells, but is more abundant in the intestinal mucosa, within a population of lymphocytes called intraepithelial lymphocytes (IEL).
Gamma-delta immune T cells are characterized by a number of features 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, T cells (γδ) 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.
The keto diet leads to increased presence of immune T (γδ) cells and their depletion 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 the low carbohydrate content of foods, the body behaves as if it is fasting, even if it is not, and begins to burn fat 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 fuel source.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.
Additionally, mice lacking immune γδ T cells exhibited impaired glucose homeostasis, leading to increased blood glucose levels.
The keto diet reduces the risk of diabetes and inflammation and also improves the body's metabolism, scientists noted.After a week on the keto diet, the mice showed reduced blood sugar and inflammation.
But when the body is in this "hungry, not hungry" mode for a long enough period of time (more than 1 to 2 weeks), fat accumulation occurs simultaneously with its breakdown, scientists have found.When the mice continued to eat a high-fat, low-carb diet, they consumed more fat than their bodies could burn.And then the signs of diabetes and obesity started 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 keto flu and usually ends within a few days.The 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 a low-carb diet for the first few weeks.This can cause your body to burn more fat before completely eliminating carbs 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 can help.Try taking 3,000 to 4,000 mg of sodium (salt), 1,000 mg of potassium, and 300 mg of magnesium daily to reduce side effects.