Ketogenic diet pros and cons
The main principles of the ketogenic diet
The ketogenic diet is based on limiting the supply of carbohydrates to about 5-10% of total daily energy intake, putting one's body into a state of ketosis, in which the body converts fatty acids into ketone bodies, which are an alternative energy source for the brain and muscles. Protein intake should be between 15 and 25% of daily caloric needs, as this prevents the process of gluconeogenesis, which could interfere with maintaining ketosis. The predominant macronutrient in a ketogenic diet is fat, which should account for 70 to 80% of the daily caloric supply, which is crucial for stimulating the production of ketone bodies. It is important to maintain an adequate ratio of omega-3 to omega-6 fatty acids to minimize the risk of inflammation and support hormonal balance. Fiber intake should be monitored to avoid intestinal peristalsis problems, typical with low carbohydrate intake. In a ketogenic diet, it is also necessary to closely monitor electrolyte levels, especially sodium, potassium and magnesium, to prevent electrolyte imbalances, a common problem during adaptation to ketosis.
What is the mechanism of action of the ketogenic diet?
Under normal physiological conditions, glucose is the main source of energy for cells, especially the brain, which prefers glucose because of the blood-brain barrier. However, when glucose availability is significantly reduced, resulting from a low carbohydrate supply, liver glycogen stores are depleted, forcing a switch to alternative energy sources. As a result of this process, the liver initiates lipolysis, breaking down triglycerides into fatty acids and glycerol. Fatty acids are then converted in the mitochondria of hepatocytes into acetyl-CoA, which is condensed to form ketone bodies such as acetone, beta-hydroxybutyrate and acetoacetate. Ketone bodies are transported by the blood to various tissues, where they serve as an energy substrate, replacing glucose. The brain adapts to use beta-hydroxybutyrate as its main source of energy, which reduces its dependence on glucose and leads to a decrease in insulin production, thereby reducing lipogenesis.
Products to consider on a keto diet
On a ketogenic diet, it is worth including foods rich in healthy fats, such as avocado and olive oil, which provide monounsaturated fatty acids that support heart health. Oily fish, such as salmon, mackerel and sardines, are excellent sources of omega-3 fatty acids, which have anti-inflammatory effects and support brain function. High-fat meats, such as beef, pork and lamb, provide not only protein, but also saturated fats needed for the production of ketone bodies. Eggs are a versatile ingredient in the keto diet, providing both protein and fat, as well as vitamins and minerals such as choline. High-fat dairy products, such as butter, cream and full-fat cheese, are high in fat and low in carbohydrates. Low-carbohydrate vegetables such as broccoli, cauliflower and spinach provide fiber and essential micronutrients, with minimal impact on blood sugar levels. Nuts, including almonds, hazelnuts, cashews and Brazil nuts, are excellent sources of healthy fats, fiber and protein, and contain essential minerals.
What foods should be eliminated from the menu?
When deciding to implement a keto diet, eliminate all carbohydrate-rich foods such as bread, pasta, rice and potatoes, as they significantly raise blood glucose levels, making it difficult to achieve ketosis. Fruits with high sugar content, such as bananas, grapes and mangoes, should also be excluded from the menu, as they provide significant amounts of fructose. Processed foods, including sweets, pastries, and sodas, contain a high amount of simple sugars that destabilize insulin levels and prevent a state of ketosis. Starchy foods, including corn and pumpkin, should also be limited due to their ability to quickly raise blood sugar levels. Dairy products high in lactose, such as milk and yogurt, should be limited because lactose is a sugar that raises insulin levels.
Benefits of the keto diet
Reduction in insulin levels leads to a reduction in lipogenesis and stimulation of lipolysis, promoting effective fat burning and weight loss. Through the production of ketone bodies, such as beta-hydroxybutyrate, the brain receives a stable and efficient source of energy, leading to improved cognitive function and a reduction in neurological symptoms in certain conditions, such as drug-resistant epilepsy. Reducing blood glucose and insulin levels also promotes a reduction in oxidative stress and inflammation, which can help reduce the risk of cardiovascular disease. The keto diet also affects the modulation of signaling pathways such as mTOR and AMPK, promoting the processes of autophagy and cellular regeneration, and thus have an anti-aging effect. Introducing a ketogenic diet can also improve blood lipid profile, increasing HDL levels and lowering triglycerides.
Disadvantages of the ketogenic diet
One of the main difficulties is the risk of vitamin and mineral deficiencies, such as magnesium, potassium, calcium and B vitamins, due to the limited variety of products consumed. Reduced fiber supply, resulting from the elimination of many fruits, vegetables and whole grain products, can lead to digestive problems such as constipation. The keto diet can also lead to increased stress on the kidneys, especially in people with pre-existing kidney problems, due to higher protein intake and increased production of ketone bodies. The state of ketosis can cause side effects such as "keto-flu," manifested by fatigue, headaches, nausea and weakness, especially in the initial phase of adaptation. Long-term use of a ketogenic diet can increase the risk of developing lipid disorders, including an increase in LDL cholesterol, which can have a negative impact on heart health. There is also a risk of hypoglycemia, especially in people taking diabetes medications, due to the drastic restriction of carbohydrates. The keto diet can affect hormonal balance, especially in women, potentially leading to menstrual disorders and other hormonal problems.
