Other recent studies have revealed other classes of altered autoantibodies in patients suffering from eating disorders, especially in patients affected by anorexia nervosa, including increased levels of IgG against ACTH [158,159,160]; IgG leptin-neutralizing autoantibodies have been identified in healthy individuals with reduced BMI, while diminished affinity of the same autoantibodies has been found in obese patients [154]. This evidence concerns the gene POMC and anorexia nervosa.