Body concerns and BMI as predictors of disordered eating and body mass in girls: An 18-year longitudinal investigation

Body concerns (e.g., body dissatisfaction and weight preoccupation) are well-supported prospective risk factors for the development of eating disorders in women. Body concerns are psychological variables but they are partly based on actual body mass. This study tested whether (a) body concerns predict increases in eating disorder characteristics measured both continuously (via subscale scores on the Minnesota Eating Behavior Survey (MEBS) and categorically (via transition to a probable or definite eating disorder), (b) body concerns predict changes in BMI, and (c) BMI predicts changes in eating disorder symptoms or development of an eating disorder. Beginning with 762 girls at age 11, the MEBS' Body Dissatisfaction (BD) and Weight Preoccupation (WP) scales were used to predict change in the MEBS' Bulimic Behavior scale (the sum of the Binge Eating and Compensatory Behaviors scales), in BD and WP themselves and in BMI over 18 years of follow up. Baseline BMI was also used to predict BMI and MEBS change. Contrary to expectations, BD and WP predicted significantly reduced growth in all MEBS scales and also predicted significantly reduced growth in BMI. BD, WP and BMI did not predict development of an ED. This pattern was strengthened when predictors were measured at age 17 instead of 11. We consider the possibility that the divergence between the current findings and past findings on eating disorder risk factors may stem from the unusually long developmental period studied, ranging from age 11 (or 17) through age 29. Additional longitudinal research that spans a similar developmental period could shed light on the plausibility of this explanation.