Guidelines on Long-term Medical Fasting

* INCLUSION CRITERIA: Clinic criteria * Long-term fasting (≥ 4 days, max. kcal: 25% of daily energy needs\*) is offered under medical supervision by medical doctors (MDs) / naturopathic doctors (NDs) * Long-term fasting has been implemented as a therapeutic intervention for more than 4 years * ≥ 50 patients / year and / or more than 200 cases in the last 10 years treated with long-term fasting Personal criteria * I am a medical doctor (MD) / naturopathic doctor (ND) * I have 4 years of experience or more in the treatment of patients with long-term fasting (≥ 4 days, max. kcal: 25% of daily energy needs\*) * ≥ 50 patients / year and / or more than 200 cases in the last 10 years treated with long-term fasting * according to the recently published fasting terminology in Cell Met.: International consensus on fasting terminology FASTING REGIMEN DEFINITIONS · Therapeutic / medically supervised fasting: Therapeutic fasting refers to any fasting regimen that is applied as a therapeutic intervention. Comment: therapeutic fasting interventions are individually tailored to a person's age, sex, body composition, physical activity level, occupation, goal, and planned duration of fasting. Medically supervised fasting refers to any fasting regimen that is applied as a therapeutic intervention by a trained physician or similar credentialed healthcare provider. * Long-term fasting: Prolonged fasting (PF), also called long-term fasting (LTF), refers to fasting regimens lasting ≥4 consecutive days. * Buchinger therapeutic fasting: Buchinger therapeutic fasting is a fluid-only fasting regimen, allowing for a maximum of 500 kcal/day and lasting at least 5 days, practiced for the prevention or treatment of diseases as well as to support one's individual health, taking into account a person's medical, psychosocial, and spiritual dimensions. It is usually accompanied by bowel/colon cleansing procedures and preceded and followed by a few days of a calorie-restricted, easily digestible diet. * Fasting-mimicking diet: A fasting-mimicking diet (FMD) specifies any diet specifically composed to induce the metabolic effects of fasting while allowing for a potentially higher caloric intake, including solid foods. It usually refers to a plant-based, calorie-restricted diet with a maximum of approximately 1,000 kcal/day that lasts 3-7 days. FMDs are usually relatively low in refined sugars and starch, low in protein, and high in plant-based fats. * FX Mayr therapy: FX Mayr therapy or FX-Mayr cure refers to a regimen containing elements of water-only fasting, a very low-calorie diet with a training of "proper chewing" in order to help individuals (re-)gain their sense of satiety, and an easily digestible diet toward the end of the treatment. The dietary intervention is accompanied by bowel cleansing procedures and manual treatments focusing on the abdominal region.