Low carb - the fight against carbohydrates?

The proportion of overweight people in the population is increasing. Not at least because of this, diets for weight reduction are still in favour. While most diets are based on a low-fat and therefore often severely calorie-reduced diet, low carb diets are low-carbohydrate diets with a more or less pronounced reduction in carbohydrates - depending on which low carb diet you follow. This article will look at what exactly is meant by this and for whom these diets are suitable.

Low-carbohydrate diets

Although fat intake relative to total calories has tended to decline in Germany over the past two decades, the proportion of overweight people has continued to rise - along with the consumption of sugary foods. For many, the logical consequence of this is to reduce the proportion of carbohydrates in the diet instead of the proportion of fat. The intake of fat and protein is usually not clearly limited. There is no exact definition of when a diet is low carb - the various concepts are too different for that. Typically, the proportion of carbohydrates in the total energy intake is around 5-30% (instead of about 50% in a "normal" balanced diet). The lowest proportion of carbohydrates is found in the so-called ketogenic diets, such as the Atkins diet. Here, changes the metabolism after a certain time so that it metabolises fat instead of glucose or glycogen for energy production. This leads to the formation of ketone bodies, which can be detected in the urine.

Slim thanks low-carb?

If you want to lose weight without carbohydrates, you should not expect too much. Studies have shown that weight loss over six to 12 months on a low carb diet is rather moderate and comparable to normal diets. It is true that there is rapid weight loss in the initial phase. But this is primarily water due to the breakdown of glycogen from our body. Glycogen is the carbohydrate store in the liver and muscles to which water is bound. Only when the diet is followed for a long time does the breakdown of fat reserves occur. As with most diets, it is important to have stamina and patience in order to achieve long-term success and not succumb to the well-known yo-yo effect. As with other diets, side effects can also occur. These include headache, fatigue, tiredness or constipation, which can be explained by the change in the body's metabolism due to the low intake of carbohydrates and fibre. In addition, caution is advised with ketogenic diets: Due to the increased concentration of ketone bodies in the blood, an over-acidification in the organism can occur, a so-called acidosis, which can lead to a breakdown of calcium from the bones - however, this is mostly the result of a long-term carbohydrate restriction instead of a short-term diet. In diabetics, acidosis can lead to diabetic coma.

The application in practice 

In principle, low carb diets are followed as strictly as low fat diets. The advantage is that by avoiding blood sugar peaks and the strong saturation effect of proteins, cravings and the feeling of hunger can be kept in bounds during the diet. Certainly there are people who can benefit from a low-carbohydrate diet - but this depends on the individual metabolism. However, which group of people specifically would benefit from a low-carbohydrate diet has not yet been clarified - the data is too limited. Moreover, this is to some extent in line with the growing realisation that personal nutrition is a highly individual matter - and should therefore follow a personalised nutrition approach rather than generalised dietary recommendations. As research on metabolism-specific diets is still in early stages, the primary focus should remain on ensuring that the diet chosen fits one's lifestyle, includes food preferences, is balanced and can be followed over the long term - only in this way sustainable success can be achieved.

The topic "Personalised Nutrition" concerns everyone! Take the chance to engage intensively with this multifaceted topic, get inspired and network at the third NEWTRITION X. Innovation Summit on Personalised Nutrition. On October 12, 2021 live in Cologne and as a livestream. Learn more at

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