The influence of sex on dietary trends, eating habits, and nutrition self-assessment and beliefs of a group of college students at a large Midwestern university was investigated. A questionnaire was completed by 105 male and 181 female undergraduate students. Men had significantly higher (P<0.0001) height, weight, and body mass index values. Significantly higher percentages of women than men had tried a low-fat diet (P=0.0075) and a low-carbohydrate diet (P=0.0285). Significantly lower percentages of women than men had never tried a diet (P=0.0173). Significantly higher percentages of women than men reported gaining nutrition knowledge from family (P=0.0033) and magazines/newspapers (P=0.0345). Significantly higher percentages of women than men agreed that they had too much sugar in their diets (P=0.0157), that it is important to limit carbohydrate consumption (P=0.0077), that it is important to limit the amount of fat consumed to lose weight (P=0.0194), and that they needed to lose weight (P<0.0001). It is important to eat a variety of foods for good health according to 94.4% of subjects. Sex differences existed in these college students with regard to anthropometric measurements, certain choices of diets, some sources of nutrition knowledge, and some nutrition beliefs.