"Epidemiological, cross-cultural, and longitudinal studies underscore the importance of the idealization of thinness and resulting weight concerns as psychosocial risk factors for eating disorders. Personality factors such as negative emotionality and perfectionism contribute to the development of eating disorders but may do so indirectly by increasing susceptibility to internalize the thin ideal or by influencing selection of peer environment. During adolescence, peers represent self-selected environments that influence risk."