Less is more – they are convinced of this: the twelve women and three men taking part in a fasting retreat in Valais. Here they eat practically nothing for a week. There are two soups and a juice every day, plus lots of exercise in the form of walking or yoga.
What seems like a sacrifice to many is actually a gain for the participants. A fall. She is not missing anything, says Karin Rohrer. On the second day of the fasting week she had some circulation problems, but otherwise she was fine. It feels good to fast here, she says.
Consciously abstaining from food is an ancient thing that is also practiced in many religions. More and more people are relying on temporary meal breaks. Intermittent fasting, in particular, has become a real hype on social media.
Types of fasting in comparison
Intermittent fasting: 16:8 or 5:2
Intermittent fasting is probably the best-known form of fasting. For example, you eat normally for eight hours and fast for 16 hours. Intermittent fasting can be easily integrated into everyday life, especially for people who don’t eat breakfast often or skip dinner.
Science assumes that positive processes begin in the body after 12 hours without food. Another form of intermittent fasting is the 5:2 method. You eat normally five days a week and don’t eat anything on two days.
During a fasting week, fasting is carried out under the professional supervision of a fasting leader or a doctor. Foods such as meat, alcohol or coffee are often reduced before the retreat and food intake is limited to soups or juices during the week. Many describe Lent as a time of retreat.
Fasting in a group can provide support. It’s not possible to say in general terms whether one week of fasting or intermittent fasting is better, says fasting leader Nadja Niggl. A week of fasting can provide many new boosts, while intermittent fasting can be better integrated into everyday life.
With the so-called warrior diet, the period in which food can be consumed is even shorter – it is limited to four hours. The fasting time is therefore 20 hours. Proponents are convinced that the Warrior Diet is intended to bring even more good stuff into the body. Nutritionists tend to advise against this form, especially for beginners, as the risk of nutrient deficiency is high.
Intermittent fasting involves not eating anything for 16 hours (see box). Most people simply skip breakfast. Nadja Niggl, head of Valais Lent Week, also feels the trend. She is pleased that more and more people are trying this form of nutrition and also notices that more and more young people and men are interested in fasting.
Fasting helps me get off the express train, pause, and breathe deeply.
At the retreat with fasting leader Nadja Niggl, practically no one is worried about losing weight, but rather about doing something good for themselves. Or, as Christoph Meyer says: “Get off the express train, pause and take a deep breath.”
Some group members also notice physical changes after a few days. Gilberte Stegmüller says she has fewer rheumatism problems in her fingers: “I no longer feel burning or pulling, and that’s after just a week.”
Tangible effect on health
Olaf Kaiser, from Germany, who works at nutritionist Markus Bock’s clinic, has also seen health improvements through fasting. Kaiser has had type 2 diabetes for four years and needs to inject himself with insulin every day. However, at some point the medication stopped working.
Nutritionist Bock therefore prescribed him a 14-day fast with meat broth, cottage cheese and coconut oil. Olaf Kaiser lost a total of eight kilos – and the change in metabolism also affected his blood values and diabetes.
However, these are all individual case reports and initially only reflect people’s personal experiences. Can fasting really cure disease?
Fasting has always been part of people’s way of life, says researcher Stephan Herzig of the Helmholtz Diabetes Center in Munich: “All of our genes arose at times when it was completely natural not to eat anything.”
Researchers around the world are convinced that temporarily abstaining from food can prevent many diseases and have a positive effect on health and life expectancy. In fact, more and more studies are proving positive effects.
Too much, too unhealthy, too sweet
The problem today is the constant availability of food, says Philipp Gerber, a metabolism expert at the University Hospital Zurich. «The fridge is always ready and full. We generally eat a lot and a lot of unhealthy things – like a lot of sugar.” Fasting can be a good counterbalance here. It is clear from studies that fasting has a positive effect on diabetes or metabolic diseases, for example. “So taking a meal break every now and then isn’t a bad thing,” says Gerber.
When fasting, our body uses its energy reserves. Metabolism changes about twelve hours after the last food intake.
The brain mainly needs sugar, glucose. To maintain the vital blood glucose level, the body first activates its liver reserves.
After about 48 hours, the sugar stores are empty. Then the body starts to burn proteins. This leads to short-term muscle loss. The insulin level drops. The body also starts to burn fat. It converts fat cells into so-called ketones. They provide energy particularly efficiently.
Many questions about fasting are still unanswered
Furthermore, an important recycling process begins: autophagy. Cellular waste, which repeatedly accumulates in many cells in the body, is initially surrounded by a biomembrane. This “garbage bag” merges with small bubbles full of enzymes. Cellular waste is recycled, for example, into microfuels.
Basic research provides good evidence for the positive effects of fasting. However, according to the metabolism specialist, many questions remain unanswered. That’s why it’s important to highlight that much of the data comes from animal research, Gerber emphasizes.
Almost no studies with evidence of efficacy in humans
There are not many human clinical studies on the effects of fasting and the statements are not clear. Researchers’ interest in studying the health effects of fasting is only slowly emerging.
According to Gerber, a big question is to what extent the positive effects can actually be attributed to fasting alone and what contribution it makes to calorie reduction. However, there is definitely evidence that alternating hunger and eating times has a positive effect because the body changes its metabolism.
The fasting group in Valais is not affected by the current state of science. They experience the positive effects of fasting firsthand – for example, when they can bite into an apple after a week without solid food. “Wonderful”, says one participant: “Feeling the juice, tasting an apple slice. Just pretty.”
Self-Experiment: What is the point of fasting for eight days?
What happens to the body when there is food deprivation? And can this also be healthy? “Puls” editor Sarah Allemann put this to the test.
Series: The Fasting Diary