Disrupted intestinal microbiota contributes to the pathogenesis of anorexia nervosa

Anorexia nervosa (AN) is an eating disorder with a high mortality affecting about 1% of women, where no evidence-based effective treatment exists. The pathogenesis likely involves genetic and environmental alterations. We hypothesized that a disrupted gut microbiota contributes to AN pathogenesis. In analyses comparing 70 AN with 77 healthy females, we found multiple taxa, functional modules, structural variants and growth rates of bacterial gut microbiota, and viral gut microbiota that were altered in AN with parts of these perturbations linked to estimates of eating behavior and mental health. In silico, causal inference analyses implied bacterial metabolites mediated parts of the impact of altered gut microbiota on AN behavior, and in vivo, fecal microbiota transplantation from AN cases to germ-free mice induced a lower body weight and hypothalamic and adipose tissue gene expressions related to aberrant energy metabolism and eating and mental behavior.