Rates of eating disorders have increased recently and are a public health concern especially among college students. Understanding variables that are associated with eating disorders could be helpful in preventing them. Participants (N = 525) were students from a large southwestern university. It was hypothesized that a desire for an underweight body mass index (BMI) would be predicted by one's ability to accurately identify one's current BMI while controlling for variables previously shown to be associated with eating behaviors, which included body dissatisfaction; drive for thinness; social physique anxiety; bulimia tendencies; dietary restraint; age; race; Greek membership; and gender were included in the regression model. Women scored higher than men on measures of social physique anxiety, body dissatisfaction, drive for thinness, and dietary restraint, although more then twice the proportion of men (49%) as compared with women (22%) were overweight or obese. Women were more accurate in correctly identifying their own BMI category. However, incorrectly identifying one's BMI was the only significant predictor of desiring an underweight BMI among women. No independent variables predicted the desire for an underweight BMI among men. Future research should assess the preventive and predictive power of accurately assessing one's BMI with eating behaviors. (Contains 3 tables.)