Social norms and diets for young women

Underweight among young women is a serious health issue in Japan, with more than 20% of women in their teens and twenties being underweight. A possible reason for this is the prevalence of social norms that dictate women should be thin for a beautiful appearance. This study investigates the effect of social norms on behaviors and attitudes toward dieting among young women by conducting online laboratory experiments at a private university in Japan. The experiments reveal that the vast majority of young women significantly overestimate the prevalence of dieting among women and the level of support for such behaviors within their university. Correcting misperceptions of these norms positively affects their attitudes toward dieting, yet no behavioral changes were observed. We bolster the external validity of our main findings using the results of an online survey with a larger national sample of women in their 20s, matched to the population distribution across prefectures of Japan. Correcting people’s misperceptions of social norms through education and advertising may effectively influence their attitudes toward healthy and balanced eating habits.