Americans frequently eat fast foods, but do college students? The objective was to determine the influence of sex on fast-food consumption and nutrition self-assessments and beliefs of a group of college students. The hypothesis was that some sex differences would be observed. Volunteers, 101 men and 158 women, 19 to 24 years of age, enrolled at a Midwestern university served as subjects. The subjects completed a 12-item written questionnaire. Five and seven percent of the students typically ate lunch and dinner, respectively, at a fast-food restaurant. The predominant reasons given for eating at fast-food restaurants were "limited time," "enjoy taste," "eat with family/friends," and "inexpensive and economical." A larger (P = .0592) percentage of men than women reported eating at fast-food restaurants because they thought these restaurants were "inexpensive and economical." Most of the subjects reported eating at fast-food restaurants 1 to 3 times weekly. The frequency of eating at fast-food restaurants was significantly different for men than for women (P < .01) as was the response distribution for considering the energy content of items on a fast-food menu when making their selections (P < .0001). Body mass indices of men were significantly higher (P < .0001) than those of women. A significantly higher (P < .0001) percentage of women than men strongly agreed with the statement that "the nutrition content of food is important to me." Several sex differences were observed in the fast-food consumption and nutrition beliefs of these college students.