The ketogenic diet (keto diet) contains about 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 seizures.
However, as a new study has found, following a 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 provide some health benefits.
More than 20 studies have shown that this type of diet can help you lose weight and improve your health.The ketogenic diet may even have some benefits 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 diets.Following this diet results in a drastic reduction in carbohydrate intake and their replacement with fats and proteins.This significantly reduces the body's use of carbohydrates and shifts the body to using fat as its primary 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 extremely efficient at burning fat for energy.
The ketogenic diet can significantly reduce blood sugar and insulin levels.This, along with increased ketone levels, shows a number of beneficial benefits to the body.
However, the keto diet can be dangerous for people with type 1 diabetes.
Benefits of the keto diet
A study of 63 people created two groups: a low-fat diet group or a low-carbohydrate diet group.The group of people on a low-fat diet had their calories restricted.This study continued for 12 months.
The low-carb group lost more weight, 7.3% of 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 statistically significant at 12 months.At the end of the experiment, there was no difference in weight between the groups.
It's worth noting that the low-carb group (keto diet) had elevated blood triglyceride and HDL concentrations, but other biomarkers were similar between groups.
If we analyze 23 known human clinical studies evaluating the effectiveness of low-carbohydrate diets (keto diets), we can draw general conclusions about these studies.Most studies achieve a statistically significant difference in weight loss (always favoring a low-carbohydrate diet).
There are several other factors worth noting:
- Low-carb diets typically result in 2-3 times more weight loss than low-fat diets.In some cases there is no significant difference.
- In most cases, calories were restricted in the low-fat group, while the low-carb group could eat as much as they wanted.
- When all subject groups restricted calories, low-carb diets still showed greater body weight loss, although this was not always significant.
- There was only one study in which the low-fat group lost more weight, although the difference was small (0.5 kg) and not statistically significant.
- In some studies, weight loss occurred the earliest.Then, people start gaining weight again over time and after they exit the keto diet.
- When scientists look at belly fat (bad visceral fat), low-carb diets have 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 foods and the appetite-suppressing effects of this style of eating.This results in a significant 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, in turn, 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 activity of immune cells called gamma delta T cells (γδ T cells), tissue-specific cells that help reduce the risk of diabetes and inflammation.
Gamma delta T cells are immune T cells that have a special T-cell receptor (TCR) on their surface.Most T cells are αβ (alpha beta) T cells whose TCR is composed of two glycoprotein chains called the TCR α (alpha) and β (beta) chains.In contrast, gamma delta (γδ) T cells have a TCR consisting of one γ (gamma) chain and one δ (delta) chain.This group of T cells tends to be less abundant—approximately 4–10% of total T cells—than αβ T cells, but is highest in density in the intestinal mucosa, in a population of lymphocytes known as intraepithelial lymphocytes (IEL).
Gamma-delta immune T cells are characterized by several features that place them between the boundaries of the more evolutionarily primitive innate immune system, which provides rapid responses 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 are capable of having long-term memory to respond more quickly to pathogens when they are encountered again in the future.
The keto diet leads to increased presence of immune T cells (γδ) and their depletion in adipose tissue
Study author Dr. Vishwa Deep Dixit of the Yale School of Medicine said the keto diet tricks the body into burning fat.When sugar levels in the body decrease due to low carbohydrate content in food, the body acts as if it is in a fasting state, even though 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 reduce inflammation mediated by NLRP3, a cellular protein involved in activating the inflammatory interleukins IL-1b and IL-18.
The process of reducing the amount of carbohydrates in food, in turn, begins to produce ketone bodies (ketones) as an alternative fuel source.As the body burns ketone bodies, protective gamma delta T cells spread throughout the body.And the number of these protective immune cells in fat tissue decreased 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.
Furthermore, mice lacking immune γδ T cells show impaired glucose homeostasis, leading to increased blood glucose concentrations.
Scientists note that the keto diet reduces the risk of diabetes and inflammation, while also improving the body's metabolism.After a week on the keto diet, mice showed reduced blood sugar levels and inflammation.
But scientists have discovered that when the body is in this "not hungry" mode for a long enough period of time (more than 1-2 weeks), the accumulation of fat occurs simultaneously with its decomposition.When the mice continued to eat the high-fat, low-carbohydrate diet, they consumed more fat than their bodies could burn.And then signs of diabetes and obesity begin 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 is often called the keto flu and usually ends within a few days.The keto flu includes low body energy and impaired mental function, increased hunger, difficulty sleeping, 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 train your body to burn more fat before you completely eliminate carbohydrates from your diet.
The keto diet can also change the water and mineral balance in your body, so adding extra salt to your meals or taking a mineral supplement may help.Try taking 3,000-4,000 mg of sodium (salt), 1,000 mg of potassium, and 300 mg of magnesium each day to reduce side effects.