Fasting therapy - an expert panel update of the 2002 consensus guidelines.

Fasting for medical purpose (fasting therapy) has a long tradition in Europe and is established as a defined therapeutic approach in specialized fasting hospitals or within clinical departments for integrative medicine. In 2002, the first guidelines for fasting therapy were published following an expert consensus conference; here we present a revised update elaborated by an expert panel. Historical aspects and definitions, indications, methods, forms, and accompanying procedures of fasting as well as safety and quality criteria of fasting interventions are described. Fasting has shown beneficial effects in various chronic diseases with highest level of evidence for rheumatic diseases. Preliminary clinical and observational data and recently revealed mechanisms of fasting and caloric restriction indicate beneficial effects of fasting also in other chronic conditions such as metabolic diseases, pain syndromes, hypertension, chronic inflammatory diseases, atopic diseases, and psychosomatic disorders. Fasting can also be applied for preventing diseases in healthy subjects. In order to guarantee successful use of fasting and to ensure adherence of all safety and quality standards it is mandatory that all interventions during fasting are guided/accompanied by physicians/therapists trained and certified in fasting therapy.