Objective: This study explored whether nutrition knowledge interacted with evaluations of a food's healthiness to influence food attitudes (ie, global evaluations). Since attitudes guide behavior, understanding factors that impact food attitudes is one way to understand food selection and why factors such as nutrition knowledge have only a modest impact on food selection. We hypothesized that the relation between health evaluations and food attitudes would be stronger for people high in nutrition knowledge. We also explored the macronutrient composition of foods, and how it related to attitudes and health evaluations. Design: Survey employing multilevel analyses to examine within-and between-subject influences on food attitudes. Setting: Student unions at two universities in the Southwestern US. Subjects: A total of 138 participants (mean age ¼ 19.8; 69 males, 67 females, two unreported). Interventions: Participants indicated their attitudes toward; experience with; and health, flavor, and affective evaluations of 24 foods before and after lunch and completed questionnaires assessing individual difference variables. Results: Experience and evaluations of healthiness, flavor, positive affect, and negative affect all predicted food attitudes. Health evaluations were more strongly associated with attitudes for people high in nutrition knowledge. Conclusions: These findings suggest a mechanism through which individual differences impact food attitudes and thus likely influence food selection.