This exploratory study compared motivation for eating between individuals from two different cultures that have moved through the nutrition transition at different rates and to different degrees. The analysis was based on a convenience sample of 1218 participants aged >or=18 years attending colleges in the US and Japan. The Motivation for Eating Scale (MFES) was used to evaluate different motivations for eating by nation and gender. The MFES consists of 12 items classified into three subscales: emotional, physical and environmental eating. The questionnaire used in the study also included responses about participants' motivation to lose weight, frequency of dieting, presence of previous or existing eating disorders, and frequency of exercise. Results showed no significant differences in the three MFES subscales for men in the US and Japan. For women, however, significant differences were seen for all three subscales. Women in the US were more likely to initiate eating for emotional reasons, while women in Japan were more likely to eat for physical or environmental reasons. Women and men in the US were more likely than the Japanese respondents to eat in response to watching TV or movies. These results suggest that there are national differences in the cultural environment that may impact individual motivations for eating. As such, various cultural perceptions of food should be considered in attempts to understand more fully the mechanics of the nutrition transition as it operates within a given country. By extension, public health policies and health promotion initiatives that are designed to limit the negative impacts of the nutrition transition may benefit from a greater understanding of the larger role that cultural perceptions of food may play in influencing individual motivations for eating.