The fasting diet was created from an attempt to determine the threshold above which the positive effects of fasting begin. The researchers tried to find out from which food intake fasting could still be considered effective. It turned out that a dietary intake of around 600 calories per day is enough to make the positive effects of fasting noticeable. In addition, a five-day fast leads to positive metabolic changes that can last for months. Clinical trials have confirmed the effectiveness of fasting as a complementary therapy to cancer treatment. The fasting cure can also be carried out at home without having to strictly follow an official diet plan. By controlling calorie intake and choosing foods wisely, individuals can imitate the effects of fasting. Recent research shows that fasting contributes to a reduction in biological age by several years after Klemera-Doubal. In addition, it influences a measure of the aging of the immune system, which leads to fascinating results in this area of research.