The ketogenic diet is a diet based on a process called ketosis. It is a specific state of the body, which is characterized by an elevated level of ketones in the blood, which occurs due to the conversion of fats into fatty acids and ketones. This occurs when the body gets only very small amounts of carbohydrates for a certain period of time. When you start on this type of diet, your body goes through several changes. After 24-48 hours from the start of this diet, the body begins to use ketones to use the energy stored in fat cells more efficiently. In other words, the main source of energy becomes fat (fatty acids), instead of carbohydrates (glucose). Therefore, during ketosis, it is not a problem to eat foods with higher amounts of fat than would seem reasonable. In this way the body loses weight quickly (specifically fat). Also, the loss of muscle tissue (protein) is minimal, as the vast majority of foods eaten during ketosis also contain relatively large amounts of protein that is good for your muscles.
Although ketosis is the foundation of the ketogenic type of diet, in its strictest form it doesn’t need to be maintained for very long. The state of ketosis can be maintained until body weight is only a few pounds higher than desired. Then, foods with a greater amount of carbohydrates (rice, beans,…) are gradually introduced. In this period, it would be very useful to keep a food intake diary in which the daily amounts of carbohydrates ingested would be recorded. That way, you can find the maximum amount of carbs per day that will still keep you from gaining weight. Once you discover this parameter, you will no longer have problems related to being overweight, because until then you will surely learn to take into account the calories and the amounts of carbohydrates, proteins and fats that you consume daily. This way you will know your body better, in terms of the maximum “allowed” daily intake. Therefore, we could say that the ketogenic diet is, in a way, a habit-learning procedure that will ensure that you never return to the old, potentially problematic levels of being overweight.
There are many types of ketogenic diets that can be found online or in other sources, but they all have one basic principle in common: high amounts of protein and fat, and minimal amounts of carbohydrates. The exact diet you will choose is not that important, as long as it allows you to get into ketosis, which is the basis of the biological mechanism that will help you lose weight efficiently.