What happens in the body when fasting?

Fasting is considered chic and good for your health. Detoxifying the body and cleansing the mind sounds tempting. But what happens in the body during fasting?

What is fasting

Every year on Ash Wednesday, the pre-Easter Lent begins for Catholics. The renunciation of solid food is aimed at the purification of body and soul and should help to reflect on the relationship with God. In addition to this religious tradition, there is also fasting for medical and therapeutic reasons. And more and more people are fasting in spring as a kind of break to find peace, relaxation and inner balance.

In contrast to starvation, one understands by the voluntary renunciation of solid food and stimulants such as alcohol and nicotine for a limited period. While fasting doctors, clinics and book authors consistently promote fasting as a healthy means of detoxification, nutritionists and nutritionists see such a cure quite critically.

Forms of fasting

Zero diets: In the strictest form of fasting, only 2 to three litres of energy-free drinks (water, mineral water or) are drunk per day.

Therapeutic fasting according to Buchinger: The term “therapeutic fasting” was introduced in 1935 by the doctor Dr Otto Buchinger and, in addition to therapeutic fasting (for example for metabolic diseases), it also includes the preventive side of fasting for healthy people. A therapeutic fasting course lasts a maximum of 3-4 weeks. This includes preparing for fasting. A colon cleanses on the first day of fasting and adequate fluid intake (tea, vegetable broth, fruit juice and mineral water). In a build-up phase of at least three days, the energy supply is gradually increased again at the end of the treatment.

Modified fasting, also called protein-substituted fasting, is used in clinics under medical supervision for the therapy of massive obesity (obesity). Protein, carbohydrates and fat are also absorbed and supplemented with sufficient fluids (2-3 litres/day), vitamins and minerals.

In the “whey drinking cure”, 1 litre of cure whey (enriched with protein and carbohydrates) is drunk throughout the day, supplemented by herbal and fruit teas up to 3 litres/day. This form of fasting also counteracts the breakdown of the body’s protein.

What happens in the body

By taking salt solutions, sauerkraut juice or enemas, all digestive residues are flushed out first. Within the first three days, the body then switches to “internal” nutrition, the hunger metabolism and draws its energy increasingly from the body’s own fat and protein. During these three days, there can also be unpleasant side effects: skin reactions, gloomy mood.

Are there any health risks?

Total fasting, i.e. the zero diet, can be associated with considerable health risks: According to the Society for Nutritional Medicine and Dietetics in Aachen, the organism uses muscle protein during fasting to cover its protein requirements and breaks it down. The result: the muscles shrink and have to be laboriously rebuilt after the treatment. The heart muscle can also be affected by this muscle “overexploitation” – dangerous for people with heart disease. People with diabetes, cancer patients and pregnant and breastfeeding women should generally refrain from fasting.

Fasting can also have negative consequences for healthy people because the defences of the organism are weakened by not eating. Fasting people can, therefore, become more susceptible to infectious diseases. To eliminate possible risks from the outset, a doctor should be consulted before a fasting cure – regardless of the form. Longer treatments – over several weeks – should also only be done under medical supervision.

Is fasting good for losing weight?

If you are extremely overweight, modified fasting may be useful, for example, if you need to lose weight quickly (before an operation, etc.). Fasting is under medical supervision. The daily intake of protein curbs the muscle breakdown, and the basal metabolic rate does not decrease as much.

In the past, total fasting was considered an effective method for losing weight. That is long out of date. Because after the quick success, you often have the lost pounds back on your hips just as quickly and damage to health cannot be ruled out with this radical cure.

“Therapeutic fasting” also leads to fat loss and a reduction in the basal metabolic rate, but here too, the yo-yo effect is pre-programmed as soon as you usually eat again. A fast on its own does not change any bad eating habits. The only thing that helps is to change your diet in the long term.

Does Fasting Help Detoxify?

Fasting means consciously avoiding meat, sweets, alcohol and cigarettes for a while. Fasting can, therefore, also be an impetus for a positive, health-conscious change in one’s lifestyle. Also, fasting is often practised as an inner form, whereby the body’s natural purification and detoxification mechanisms are stimulated, and the self-healing powers are to be awakened.

According to the German Nutrition Society, the term “purification” cannot be scientifically justified, since there is no accumulation of waste products and metabolic end products in a healthy human body. Substances that cannot be used are excreted via the intestines and kidneys if there is sufficient fluid intake.