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Why is fasting healthy?

Barbara Philipps - 21/06/2024 - 0 comments


Why is fasting healthy?

Scientific studies clearly show that fasting is the most effective therapeutic strategy for longevity. In other words, fasting helps you live a long, healthy and fulfilling life as well as enhancing your physical and mental wellbeing. But how does fasting work and why it is so healthy for us? In this article, we look at some of the positive changes that take place in the body when we fast.

Fasting according to Dr. Otto Buchinger: Our insights

When we talk about fasting, we are referring to the therapeutic fasting method developed by Dr. Otto Buchinger, the founder of our fasting clinic in Überlingen on Lake Constance. His medical insights form the basis for the holistic concept we still work with today and are continuously evolving. Dr. Otto Buchinger developed his fasting programme based on his own experience:

Fasting saved his life after he fell ill with rheumatic fever. His first, unsuccessful experience with water fasting inspired him to dedicate his life to creating a programme that was easier to tolerate while retaining the full benefits of fasting. As a deeply religious person, Dr. Buchinger emphasised the importance of spiritual aspects and fasting in a community as integral dimensions of fasting, in addition to its medical benefits. He believed that therapeutic fasting should be accompanied by other healing methods. The following generations of the Buchinger Wilhelmi family continued to hone the method by incorporating complementary approaches such as exercise, hydrotherapy, and massages.

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„After 19 days of medical water fasting, I was weak, skinny, but could move all my joints again like a healthy recruit. It saved my life and my existence.“ 

Dr. Otto Buchinger

Why fasting is natural for humans

Fasting is a unique metabolic programme that humans have developed to cope with two natural rhythms: the alternation of day and night, which corresponds to intermittent fasting, and the alternation of seasons, corresponding to long-term fasting.

Going without food for a few hours is not only natural for the human body, but also necessary. When we sleep, our body automatically fasts for several hours – a healthy and important process. Sleep and intermittent fasting share some similarities in terms of their effects on the body and their alignment with natural circadian rhythms. Typically, we sleep at night, when darkness signals the release of sleep-inducing hormones. We generally also fast during the night, and often into the morning. This synchronization with our circadian rhythms helps to enhance the effectiveness of these processes. It may therefore not be a coincidence that fasting and sleep both promote restoration and repair, aiding the recovery and rejuvenation of bodily systems. These natural cycles are the inspiration for various fasting diets that focus on reducing caloric intake, one or several macronutrients, or the time window in which food is consumed. The most popular intermittent fasting diets include the 16/8 method (fasting for 16 hours and eating within an 8-hour window) and the 5:2 diet (eating normally for five days and restricting calories for two days).

But it is not only our circadian rhythm that dictates when we should fast: In the past, the seasons also played a major role. Long before we were able to simply buy food at a supermarket or preserve it for the winter, humans had to be able to go without nutrition for long periods during the colder months or the dry seasons.

Most animals in the wild and early humans fasted according to the rhythm of the seasons. One of the best examples of an animal that fasts is the emperor penguin. Emperor pinguins go for several months without eating while they protect their eggs against the cold in Antarctica. This remarkable species has been extensively studied by Dr. Yvon Le Maho from the University of Strasbourg, along with his colleagues Dr. Jean-Patrice Robin and Dr. Rene Grocolas. These intrepid researchers travelled to a remote station in Adélie Land, Antarctica, for over a year at a time to study these fascinating creatures. Our scientific team collaborates with these researchers on a regular basis to understand the physiology of fasting in humans. We can assure you that having dinner with one of these scientists is as thrilling as watching the best adventure movies.

At Buchinger Wilhelmi, we offer therapeutic programmes designed to leverage these natural abilities. A particular emphasis is on ensuring a gentle transition at the beginning and end of the fast. Because what you eat immediately after fasting plays a significant role in determining how long the positive effects will last.

Chronic fasting deficiency

Fasting is not just healthy; it is essential for our health. Many chronic lifestyle diseases like fatty liver and type 2 diabetes are caused by a lack of fasting. We call this “chronic fasting deficiency”. These illnesses arise because we eat too much, consume unhealthy foods, or eat at the wrong times, leading to an energy overload. The strongest evidence of this is the fact that fasting is often the most effective treatment. For example, type 2 diabetes, which is often considered incurable, can actually be reversed through fasting, while most drugs only manage the symptoms.

How long is it healthy to fast?

How healthy it is to fast also depends on how long and how often you fast. Doing it properly can be very beneficial for your body and mind. But if it is not done correctly, it can also have negative repercussions, which is why we always recommend consulting a medical professional beforehand.

The question how long you should fast is a highly individual matter. Among other things, it depends on:

  • your age
  • your state of health
  • your weight

We therefore recommend getting a professional opinion on your personal situation before you fast. At the Buchinger Wilhelmi clinics, an experienced doctor will discuss with you how long you should fast in order to stay healthy.

Example of a typical 10-day fasting stay in one of our clinics:

As a rough estimate, we give the following advice:

  • Fast every night for a certain length of time. The 16/8 intermittent fasting protocol fits well with the natural rhythms of the body. But this timing is not set in stone: If you fast 15/9 or 17/9 or adapt your intermittent fasting routine to your social life, you will still reap the benefits.
  • Fast at least once a year for a longer period of at least seven days (determined individually together with a doctor and ideally in a special facility under medical supervision). If you cannot come to a clinic, you can use our FASTING BOX.

Scientific findings on the health benefits of fasting

Fasting is associated with numerous health benefits, including physical regeneration, due to various physiological mechanisms that are triggered when you stop eating food. These include:

Autophagy activation

Fasting stimulates autophagy, a cellular process that removes damaged proteins and organelles, enabling a clean-up and regeneration of the body’s cells.

Reduced inflammation

Fasting has been shown to reduce inflammation in the body. Chronic inflammation is linked to various diseases and reducing it can help repair and regenerate tissue.

Improved metabolic health

Fasting improves insulin sensitivity and promotes metabolic flexibility. This allows the body to switch more efficiently between burning glucose and fat for energy, leading to improved metabolic health and a reduced risk of metabolic diseases.

Hormonal regulation

During fasting, the secretion of insulin growth factor 1 slows down. Reduced IGF-1 levels are associated with enhanced longevity, while elevated IGF-1 has been linked to an increased risk of certain cancers. By decreasing IGF-1 levels through fasting, we create an environment in the body that is not conducive to cancer cells. Fasting therefore acts as a powerful preventive measure.

Cellular repair processes

Fasting triggers various cellular repair processes. It enhances DNA repair mechanisms, which helps prevent mutations and maintain genomic stability.

Ketone body signalling

During fasting, ketone bodies such as β-hydroxybutyrate are produced which promote a deep regeneration state that enhances cellular resilience to stress, aiding organ repair and regeneration.

Immune system rejuvenation

Prolonged fasting leads to improved stress resistance and regeneration of hematopoietic stem cells.

Reduction of oxidative stress

Fasting increases total antioxidant levels and reduces oxidative stress, resulting in anti-ageing effects.

Fasting is proven to be beneficial for the primary and secondary prevention of various diseases. As our numerous scientific studies show, fasting has a positive effect on many metabolic processes such as cell ageing. In addition, it activates the cells’ self-cleansing mechanisms.

If you would like to learn more about the science behind fasting, take a look at the world’s largest scientific study on the effects of Buchinger therapeutic fasting.

Illnesses: Who can benefit most from fasting

Therapeutic fasting is suitable for many indications, or disease patterns. We have drawn up a list of them here. In this case, it is particularly important to consult a doctor with fasting experience. At Buchinger Wilhelmi, a physician will give you a thorough check-up and recommend how long and how often you should fast and what supplements you should take. It is difficult to give a general recommendation as everyone is different and has different needs, especially if they are ill. In our experience, for instance, patients with metabolic syndromes like obesity, high blood pressure, type 2 diabetes and insulin resistance should fast for a longer period of 15 to 21 days and then switch to a low-carb diet.

Fasting can be beneficial for chronic inflammatory diseases such as rheumatoid arthritis, fibromyalgia and activated osteoarthritis, as well as for chronic pain disorders such as migraine, irritable bowel syndrome and fibromyalgia syndrome. Due to its positive influence on patients’ state of mind, fasting can even help with exhaustion, chronic stress, and sleep disorders.

However, there are cases in which fasting is not recommended: People who are underweight, have active cancer or eating disorders should not fast. The same goes for children, pregnant women and people with gout or gallstones.

Even if fasting is not recommended during active cancer phases, we have witnessed the effectiveness of long-term fasting in preventing cancer and also in recuperating after chemotherapy.

Conclusion: Fasting can be so healthy

How healthy fasting is depends on who is fasting and how they go about it. If done properly, fasting is not only beneficial for your body, but also for your mental wellbeing, especially if you decide to spend time in a professional fasting clinic and fully immerse yourself in the experience. During a stay at our clinics, patients often exercise around four times more than in their everyday life. This includes hiking, walking, swimming, cycling, and numerous other activities available at our clinics.

Fasting should not be viewed as something you do only once; it reconnects with your body’s need to regularly switch to the fasting metabolism. We cannot repeat it often  enough: Fasting is natural and necessary for a long, healthy life.

You should also fast intermittently every day. If you want to experience fasting at home, there are various programmes that can be repeated several times a year, such as our FASTING BOX. This is a hypocaloric ketogenic diet with intermittent fasting, which has a similar effect to a short-term fast. Since it only lasts five days, it is also a great way to try out fasting for the first time before committing to a longer fast.

In a nutshell:

  • Long-term fasting has proven to be very successful in the treatment of metabolic and inflammatory diseases
  • Fasting overnight and according to the rhythm of the seasons is natural and necessary for a long, healthy life
  • Break your fast with high-quality food and take the opportunity to switch to a healthier diet

We would encourage you to consult a medical expert for more information (you can also contact us directly) and try out fasting, since it can be a real pleasure and it is good for your health in so many ways!

Video: How healthy is fasting according to science?

In this video, Dr. Françoise Wilhelmi de Toledo, explains the interplay of fasting and health. Just like sleeping and eating, fasting is a natural process that our bodies are made for. It’s not just about abstaining from food; it’s about optimizing your health. Watch the video to learn more.


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