Body composition correlates of weight dissatisfaction and dietary restraint in young women.

Previous research found that when Body Mass Index (BMI) was statistically controlled in a multiple regression model, the percentage of body fat accounted for no additional variance in dietary restraint scores among women although, on its own, it was a significant predictor of this variable. These results imply that anatomical factors, besides fatness, influence dieting behaviour. The present study was designed to compare the relative influence on dietary restraint and weight dissatisfaction, of three body composition measures, each of which contributes in a different way to subjective impressions of body size (viz. BMI, body fat content, and skeletal frame size). Measures of emotional reactivity ('neuroticism'), body dissatisfaction, , and body focus were also included in the regression model. Results indicated that these psychological variables were strongly and positively related to restraint. Frame size was also a significant predictor of restraint and weight dissatisfaction. In fact, when frame size was controlled in the regression model, neither percentage of body fat nor BMI were able to explain any additional variance in restraint scores. These findings indicate that weight concerns and dieting behaviour are influenced, at least among young women, more by the size of their skeletal structure than their degree of adiposity. The irony of these findings is obvious and disheartening. An anatomical feature which is essentially resistant to change by dieting or exercise appears to be a primary influence in women's weight dissatisfaction and their tendency to diet. It is acknowledged, however, that this relationship may not obtain among very obese women.