In addition, ghrelin is already being used in several clinical trials as a therapeutic strategy for the treatment of cachexia in chronic heart failure, cancer, end stage- renal disease or cystic fibrosis, frailty in elderly, anorexia nervosa, growth hormone deficient patients and sleep-wake regulation (e.g. major depression) [82, 83]. This evidence concerns the gene GHRL and anorexia nervosa.