Increased body mass index associated with increased harm avoidance and decreased self-directedness in Japanese women.

Previous studies have suggested that body mass index (BMI) is related to personality traits, and that there may be gender specificity in this relationship. In the present study, the association between BMI and the 7 dimensions of the Temperament and Character Inventory was investigated in 567 Japanese healthy volunteers, with special attention on gender effects. Height and weight were self-reported, and BMI was calculated from these values. In the multiple regression analyses, higher BMI was related to higher scores of harm avoidance (p < 0.05) and lower scores of self-directedness (p < 0.01) in women, whereas BMI was not related to any Temperament and Character Inventory dimension in men. The present study suggests that increasing BMI is associated with increased harm avoidance and decreased self-directedness in women but not in men in healthy subjects.