A few hundred years ago, people had to make do with the food that was available in their immediate surroundings or were starving. Even in the 21st century, in many countries of the world there is hunger or a sparse choice of food. In industrialized countries, where any kind of food is available year-round, a debate has broken out about the “right” diet. Vegan, low-carb, Paleo and many others already serve as a kind of substitute religion and straw for the disoriented in an increasingly globalized world.
The ketogenic diet moved after the increasing low carb hype (carbohydrate minimization) of recent years more and more in the focus of the public. Yet the ketogenic diet already has a longer history. A well-known form is the Atkins diet, which became known in the 1970s by the inventor Robert Atkins. Thereby, the ketogenic diet differs in one essential point from the usual low carb diets. With Low Carb parliamentary allowance carbohydrates and to a large extent on short-chain carbohydrates – speak sugar – are renounced if possible completely. The aim is to minimize fluctuations and sharp rises in blood glucose levels. The release of the hormone insulin is reduced and thus, among other things, weight loss is more easily achieved. One problem of the low-carb diet is the persistently high demand for carbohydrates – glucose to be precise – e.g. by the brain, the central nervous system or the red blood cells. If this demand is not sufficiently covered by food, the body is forced to produce glucose from other substances and mainly from protein via gluconeogenesis. In the long run, this can lead to a loss of muscle mass and a reduction in metabolism. The ketogenic diet, on the other hand, takes a completely different approach. By a very strong reduction of the carbohydrates to maximally 20-60 grams daily, the body changes its metabolism. Certain cells – like the red blood cells – must be supplied further over the production of sugar by the Glukoneogenese, the musculature and particularly the brain begin however to use alternative energy carriers: the Ketonkörper. Ketone bodies, or ketones for short, are produced by the liver after a certain period of carbohydrate reduction. The body is then increasingly in a state of ketosis. Colloquially, this state is often dubbed a starvation state, since ketosis occurs during starvation or fasting. However, it is not necessary to starve to reach ketosis. If the carbohydrate intake is reduced, but still sufficient energy in the form of fat and protein is supplied, the body enters the state of ketosis without starvation.
The transition of the metabolism until ketosis occurs can vary greatly from person to person. With pure water fasting (fasting without the intake of calories), ketosis usually sets in within the first three days. In fasting cures with radical calorie reduction, the body also begins relatively quickly with the production of ketone bodies to ensure the energy supply of the brain, among other things. During the period of the changeover, body proteins are also always broken down. Particularly with sporty activity during the fasting, the body also falls back on the muscle protein, in order to manufacture missing glucose, which can be shown by increased liver values (ALT, GPT) of perseverance sportsmen occasionally. Fasting diets stimulate what is known as autophagy. This term has a very positive connotation among followers of fasting. Autophagy means that cells break down and utilize their own components. In the process, old and no longer fully functional or damaged “material” can be disposed of. Autophagy can thus be helpful in some diseases or even prevent diseases. However, it is not an ultimate cure and not necessarily to be equated with “cleansing”. It is now known that cancer cells can increase their development through autophagy. This does not mean that cancer cells are stimulated to grow by fasting, however, it also does not mean that fasting can “cleanse” the body from harmful diseases. However with chamfering by missing food on existing substances in the body one falls back and this preferably on substances, which are no longer needed. A strong reduction of calories – as with fasting – inevitably leads to the throttling of the metabolic rate as well as the loss of muscle mass. Since furthermore a fasting cure only maintains a certain time, many go the way over the ketogenic nutrition to the reaching of the Ketose. This has the advantage that starvation is not necessary, so the daily calorie intake can be covered by fat and protein, which also keeps the loss of muscle mass low. The ketogenic diet can be maintained for life. The disadvantage is that the change takes more time. For those with a high carbohydrate-based energy intake, the transition can take weeks to months. During this time, a so-called “keto flu” can set in. Symptoms such as fatigue, dizziness, sleep problems, headaches and reduced concentration may occur.
Many people find it difficult to give up carbohydrates. Their body is used to getting carbohydrates with every meal and on a regular basis. The body has lost metabolic flexibility. When abstaining from food for a longer period of time or eating a meal rich in fat and/or protein without carbohydrates, people often react irritably and with restlessness. In general, it can help to do interval fasting from time to time or, as an athlete, to complete a phase with “train-low”, i.e. a training session before which the carbohydrate stores have already been emptied. A low-carb diet lasting several days also helps. The body needs certain enzymes to utilize the ketone bodies. If it has not “seen” any ketone bodies for years – or perhaps even since birth as a baby – it must learn to form the corresponding enzymes and transporters again in order to be able to process ketone bodies. In general, athletes often have some of these helpers due to their stress and the transition is easier. At the beginning of the ketogenic diet, dizziness and low blood pressure can occur with permanently low blood sugar levels. Here, the salt consumption should be kept in mind and if necessary, the salt consumption may be increased somewhat. In general, one should give oneself time and not plan a change in a phase in which there is additional physical or psychological stress. I talked to two athletes who have already made the transition and are racing their bikes in ketosis.
Sean Sakinofsky is a passionate cyclist and is best known on social media as Sean Sako. Sean eats a ketogenic diet and thus continues to achieve tremendous performances on the bike, which can be followed on the training platform Strava on his profile. For many cyclists, the question is whether you can continue to cycle ambitiously on a ketogenic diet and how that plays out in practice. I conducted an hour-long interview with Sean via Instagram, which you can find there at IGTV videos. (video in English). His girlfriend Meli (Melanie Abt) tells in a second interview (German-English) how she managed to switch to keto and what has changed for her since then.
You can read a few details from the interviews below. If you want to know more, you can watch both interviews on Instagram. At this point: many thanks to Sean and Meli for their insights and sharing their experiences!
Sean grew up in a family that ate a vegetarian diet. However, as a child, Sean had a weakened immune system since birth and as a result had health problems and some family members also became seriously ill. After the death of his father from cancer, Sean changed his diet to Keto. Since then, things have gone uphill for him and his body. He benefited significantly from his elimination of carbohydrates. Sean doesn’t make dogma out of the ketogenic diet. He believes that each person must find their own path for themselves and their diet. However, he wants to show that you can achieve great performance on the ketogenic diet and free yourself from “constant food intake” during exercise. Sugar in its form as household sugar, sucrose is for him an artificial product of the industry that can create addictive behavior.
Meli, since when do you eat ketogenic and what were your motivations for it?
Meli: I have been on a ketogenic diet for 6 months. Food had simply become the focus for me and I had to eat so much and constantly at the end and was simply hungry all day. So it was mainly the everyday life that made me want to change something and not the performance in sports. I then used my break after a hip operation to change my diet.
What does your diet look like in everyday life and in training? Has anything changed since then?
Meli: I don’t have a specific diet for days with or without training. And I don’t have to plan particularly for a ride. I feel much less stress in everyday life and on the bike my performance has improved significantly.
Would you recommend the ketogenic diet to anyone or are there limits?
Meli: Basically, anyone can try it and it is also always very individual how much carbohydrates you can eat to stay in ketosis. One says around 50 grams per day – which is really not little! I reach this rather rarely to not at all. In addition, there are also possibilities such as “Carb Cycling”, where you can take more carbohydrates now and then.
What are the biggest advantages for you?
Meli: I regenerate much better. I feel happy because my everyday life is no longer determined by food. I simply don’t have to carry so much food around with me anymore, because especially that wasn’t only the case on the bike before.
