The ketogenic diet (also known as the „keto diet“) is a diet that mimics the metabolic effects of fasting. By consuming foods rich in quality fats, with an adequate amount of protein, and a severely restricted net carbohydrate content (total carbohydrates minus fiber), the body's metabolism is rewired to use fat as the primary fuel source instead of glucose.
This change has a profound effect on metabolism in both sick and healthy individuals. Medical research has shown the potential to improve or influence a number of neurological conditions and metabolic disorders. For healthy individuals, diet serves as a tool to prevent chronic disease, optimize cognitive function, and improve body composition (fat loss).
The term „ketosis“ refers to a metabolic state in which the body produces ketone bodies (ketones) as a result of breaking down fat for energy. These fats can come directly from food or from the body's fat stores. Nutrition-induced ketosis is called „nutritional ketosis“.
Ketones are used directly by cells to fuel the body. This process is analogous to the way carbohydrates are converted into glucose. Put another way: ketones are to fat what glucose is to carbohydrates. In medical terms, the state of ketosis is defined when blood ketone levels exceed 0.5 mmol/L.
Achieving ketosis offers a wide range of benefits, from treating chronic diseases to optimizing physical performance. This way of eating appears to improve the ability of mitochondria - the „powerhouses“ of our cells - to provide the body's energy needs in a way that reduces inflammation and oxidative stress. By optimizing the way our body uses energy, we strengthen its ability to fight a range of diseases as well as cope with the stressors of modern living.
There are two main methods of switching from glucose to ketone metabolism:
The classic ketogenic diet is defined by the ratio of macronutrients (fat to protein + carbohydrates). The classic ratio is 4:1 (4 grams of fat for every gram of protein and carbs combined). There are also modified versions with a ratio of up to 2:1, depending on individual therapeutic goals. The ratio used for each individual patient depends on the therapeutic goals as well as what regimen is achievable for your lifestyle.
The main differentiating factor between them is the distribution of calories derived from protein, carbohydrate and fat - what we call the „macronutrients“ (nutrients with caloric value).
The three macronutrients differ in several key ways: their energy density and the way the body metabolizes them:
In a state of homeostasis (balance), the human body primarily uses fats and carbohydrates for energy production, while proteins serve mainly as building blocks for cell and tissue regeneration. It is important to note that with excessive protein intake, the body can trigger the process of gluconeogenesis. Here, excess protein is broken down to glucose, which leads to the same metabolic end product as carbohydrate consumption and can prevent entry into ketosis.
A minimum test period of 3 months. This period is necessary for the body to become „fat-adapted“ - a state in which the body begins to effectively and efficiently metabolize fat as its main energy source.
Although the short answer is „yes“ for the majority of people who eat the typical „Western model“ (high in processed carbohydrates and sugars), it is imperative that you consult with your personal doctor or nutritionist, before switching to keto mode. Working together with a medical professional during this process ensures optimal therapeutic outcome and safety.
The ketogenic diet has been the subject of hundreds of studies. Originally developed for the treatment of epilepsy, today it is showing promising results in conditions associated with metabolic dysregulation, including:
If you or a loved one has been diagnosed with one of the above diseases, have a genetic predisposition to developing one of them, or believe that your lifestyle and/or environmental factors may increase your chances of developing them, the ketogenic diet can be a great tool for improving your health.
Important: Before switching to a ketogenic diet, it is imperative that you consult a doctor or qualified nutritionist to ensure the safety and therapeutic effectiveness of the diet relative to your health condition.
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