Energy Through Fasting

During the first days of a fasting regimen, the intestines undergo an intensive cleansing process. Once no additional food is supplied, digestive activity is largely reduced. As the body can no longer obtain energy from external sources, it shifts its metabolism from external nourishment to internal nutrition.

The healing effects of fasting on the body are largely related to autophagocytosis, or autophagy, which begins around twelve hours after the last intake of food. This is a natural bodily response to reduced nutrient supply, in which nutrients previously obtained from food are replaced by those drawn from the body’s own reserves. During this phase, the body breaks down and recycles its own cells—a process that affects all cells, but is particularly pronounced in cells under metabolic, genotoxic, or infectious stress. This means that during fasting, mutated or damaged cells are preferentially eliminated.

For a healthy fasting process, it is important that sufficient energy is available within the body’s own cells at all times. During fasting, the body draws this energy from its internal reserves, which it has stored primarily in the form of space-efficient fat molecules. In doing so, excess fat reserves are broken down first—reserves that often also store toxins and harmful substances.

Especially at the beginning of a fasting period, the metabolism also requires proteins, which are converted into glucose or sugar to supply the brain, nervous tissue, and renal medulla with energy until these tissues shift most of their energy consumption to fat metabolism. After this transition, only small amounts of protein are needed during fasting. Once the body has adapted to a fasting metabolism, sophisticated conservation mechanisms come into effect, ensuring that available proteins and existing reserves of micronutrients such as vitamins last as long as possible.

Different Forms of Fasting

By now, it has become widely known that fasting can be beneficial for both body and mind, and there is no shortage of different fasting approaches, each with its own health promises. The fact is, however, that after about twelve hours the state of autophagy begins, and from that point the fasting metabolism is activated. Intermittent fasting makes use of this mechanism by following a daily rhythm of approximately 16 hours without food and eight hours of eating. In this practice, fasting is not a special period set apart from everyday life, but rather a daily routine integrated into normal life. Many people appreciate how easy this approach is to implement and experience positive effects on their day-to-day well-being.

Those who commit to a longer fasting period can expect not only a greater physical effect, but also a more pronounced mental and cognitive impact. Extended fasting programs usually last between five days and several weeks. However, the rule is not “the longer, the better,” but rather that healthy fasting, followed by positive lifestyle adjustments, is especially beneficial. Ideally, such fasting periods should become a ritual and be repeated on a yearly basis.

During longer fasting programs, methods such as water fasting—also known as a zero-calorie diet—are sometimes practiced. In this approach, the body is supplied with nothing but sufficient amounts of water. Other fasting methods make use of light vegetable broths and/or juices, which are consumed several times a day. Water fasting is often preceded and followed by a phase of juice fasting to ease the transition into and out of the zero-calorie phase. Some fasting regimens are also supported by enemas for intestinal cleansing, particularly high fluid intake to promote flushing, or the use of Glauber’s salt and sweating packs.

Since ancient times, fasting has not only been a healing practice but also a deeply spiritual one. To this day, it plays an important role in Hinduism and Buddhism, shapes the Islamic year through Ramadan, and has been preserved in Christianity in the pre-Easter fasting period. It is no coincidence that people seek in fasting a place of stillness—a time of clarity and reflection that sets itself apart from everyday life.

Fasting certainly represents a significant mental challenge, and people who have never fasted before often find it hard to imagine going without food for days at a time. While the first days of a fasting regimen are often accompanied by feelings of hunger and perceived as difficult, a sense of euphoria soon sets in, accompanied by a feeling of lightness and mental clarity.

"Renunciation does not take away. Renunciation gives. It gives the inexhaustible power of simplicity."

Martin Heidegger

This time of deep calm—during which, without cooking and eating, the day can seem to have more hours than usual—can be consciously used for creative pursuits, inner decluttering, and mindful reflection. Many people value fasting as a form of purification that also extends to mental burdens and emotions that are no longer needed. During fasting, they often feel particularly open to meditative, religious, and spiritual experiences.

However, this heightened openness and sensitivity also call for good self-care during this period of intensified perception. It is especially important to pay close attention to what you take in mentally through media, films, books, or radio. The altered bodily functions can make “business as usual” feel exhausting, and before embarking on a fasting regimen, it is therefore wise to carefully consider the context in which you want to experience this time. A week of vacation with no external obligations, or a guided group fast, can be particularly suitable options.

In addition to considering the context in which a fasting experience will take place, the body should also be gently prepared for the upcoming period. It is recommended to simplify the diet noticeably in the days beforehand and gradually reduce food intake.

During fasting, holism is the key concept. It is important to consider physical and emotional aspects together, to ensure a healthy and relaxed environment, to listen to one’s own body and intuition, and to allow for sufficient movement. Physical activity during fasting should consist of calm, gentle practices with an emphasis on deep breathing. Activities such as yoga or walks in nature are particularly well suited.

"Periods of fasting are part of my very being. I can no more do without them than I can without my eyes. What the eyes are for the outer world, fasting is for the inner."

Mahatma Gandhi

As a healthy individual who does not suffer from being underweight, a week-long fast can be planned and carried out independently. However, it should be noted that during a fasting metabolism, the effects of many medications can be intensified. In case of doubt, it is therefore advisable to consult with the treating physician. Fasting is strictly contraindicated during pregnancy and breastfeeding, as there is a risk of insufficient nourishment for the child and toxins released during fasting could be passed on through breast milk.

After a fasting experience, it is important to ease back gradually—both nutritionally and in terms of lifestyle. In order to carry the insights and experiences gained during fasting into the period afterward, it can be helpful to write them down. Contact with the outside world and the consumption of media can also be reintroduced step by step, while food intake is slowly brought back to a normal level. In the days following a fast, a low-fat diet based on light vegetable soups or gently steamed vegetables is recommended.