"Fasting is a moment to free your body digestive tasks, so that it draws on its reserves and cleans itself," says Gisbert Bölling, initiator in 1990 of dietary fast in France.

This very old method of self-healing, in keeping with the phenomenon "detox", is becoming more and more followers. It responds to a desire to be purified and heal the little words of everyday life. Explanations and advice before being tempted.

A deprivation of foods with multiple health benefits

Thanks to fasting, the body, which no longer has to deal with the energy-consuming assimilation of food, can indeed devote itself to eliminating toxins and regenerating cells. Dr. Françoise Wilhelmi de Toledo, nutritionist, confirms in his book The Art of Fasting : "cellular and molecular repair, weight loss, improved blood circulation and microcirculation, and the harmonization of 'mood lead to increased quality of life and increased vitality'.

In addition, a study on blood and hormonal parameters carried out on patients in hospitals and private clinics in Germany, specifies that during fasting, one sees on the one hand an increase of the cortisol (anti-inflammatory effect), of dopamine and serotonin, on the other hand a decline in insulin and thyroid hormones; which would explain emotional changes such as the sensation of fullness.

Before the diet, an essential preparation

However, it is not advisable to start this "cleaning" without medical advice. Fasting is to be avoided if you follow treatments (the side effects of the drugs would be increased tenfold) or if you have pathologies and other medical contraindications: hepatic or renal insufficiency, pregnancy ... Once your health check validated, the Ideal is to fast during a week of vacation. If you have to go to work, it will be more difficult because the first two days are very ungrateful.

One week before fasting, prepare your body by gradually reducing your food intake. Remove at J-5 animal proteins, excitants and cereals, D-3 dairy products, vegetable proteins and eggs, to eat only fruits and vegetables from D-2. This helps to minimize temporary side effects (headaches, insomnia, nausea, dizziness, skin irritation, muscle pain).

For your intestinal comfort, Thomas Uhl, naturopath, advises to perform drainage of emunctories (liver, colon kidneys) taking, each morning a week before the start of fasting, birch sap in a fruit juice. Gisbert Bölling advocates a more expeditious purge: a sachet of sodium sulphate diluted in a bottle of water to drink in the afternoon, the day before D-Day.

During fasting: the organism in self-repair mode

Meals are replaced by diluted fruit juices, herbal teas, unsalted broths (salt would bind the water in the cells instead of draining the toxins), or about 3 liters of fluid a day. In the absence of sugar, the liver and muscles release the glycogen to turn it into glucose. Once the glycogen is exhausted, the liver turns the fatty acids into ketone bodies, "a super-fat that helps the body to go into self-repair mode," adds Dr. de Toledo.

The first 48 hours, the mind suffers more than the stomach. Fasting at home requires an iron will and understanding of the surroundings. That's why the Fast and Hiking stays attract more and more amateurs.

In addition to coaching professionals, stretching, yoga and meditation come to the rescue to fade unpleasant sensations. Conferences, nutrition workshop, massage can also be on the program. From the third day, one feels an impression of lightness, even a certain euphoria.

Results: radiant complexion, weight loss and positive feedback

But a question taunts the neophytes. How to walk on an empty stomach, or almost, without fainting? Daily four-hour hikes are not marathons. These easy walks in the nature, interspersed with tea breaks, stimulate the metabolism, increase the supply of oxygen, support the burning of fat and the elimination of carbon acids by the lungs.

Other positive effects: a radiant complexion and the flight of extra pounds. Beware of the yoyo effect: the body may store fearing a next famine.

At the end of the fast, we take the preparation calendar in the opposite direction. In a week, we gradually return to a normal diet to optimize this break that has been listening to his body.

Three addresses that offer fast-hiking stays in France and abroad ...

• The Wild Thought, tel. 04 75 44 55 58, lapenseesauvage.com
• Fasting and Hiking Bölling, tel. 04 75 27 41 58, www.jeune-et-randonnee.com
• Celestial Cure Candido, tel. 06 62 75 67 89, celestecandido.com