FGF21 and anorexia nervosa: There have been very few studies on FGF21 and bone structure and strength in humans, although a small study using high-resolution computed tomography (HR-pQCT), in women with anorexia nervosa (AN) showed that serum FGF21 concentrations in both women with (AN) and normal weight (NW) as controls were inversely associated with trabecular parameters at the radius and a positive association was seen with trabecular separation contributing to a decrease in bone strength at the radius [27].