BDNF and bulimia nervosa: Eating disorders affect circulating BDNF, but whereas patients with anorexia and bulimia nervosa show consistently lower serum BDNF [119–121], data from obese subjects are contrasting, since higher [119, 122–124], lower [125], or unchanged serum levels [126], and lower [127, 128] or unchanged levels of plasma BDNF [127, 129, 130] have been described in obese compared to normal-weight subjects.