Complex sentence: Fasting has been demonstrated to have positive effects in rheumatological diseases, and preliminary observational studies suggest a therapeutic effect of medically supervised fasting in other chronic conditions such as metabolic diseases, pain syndromes, hypertension, chronic inflammatory diseases, atopic diseases, and psychosomatic disorders.
Split into simpler sentences: Fasting has been demonstrated to have positive effects in rheumatological diseases. Preliminary observational studies suggest a therapeutic effect of medically supervised fasting in other chronic conditions such as metabolic diseases, pain syndromes, hypertension, chronic inflammatory diseases, atopic diseases, and psychosomatic disorders.