Portion size is recognized as a major determinant of food intake, at least over the short term, and could be related to overconsumption and obesity. In this study, we developed and evaluated a new visual measure of portion size (PS), examined whether the PS of chicken, ice cream, and soda varied among people in Brazil, France, and the USA, and tested whether PS was related to gender, body mass index, body weight, and socioeconomic status. We conducted a cross-sectional study using online convenience samples of university students (total N = 1391). Across all three foods, French personal and country PSs were significantly smaller than the other three countries. Estimated country PS was reliably larger than personal PS. Women's personal PSs were smaller than men's, but women's and men's estimates for country PS were similar. French personal and country PSs were the lowest. Some PSs had a weak but significant correlation with SES but were not significantly related to either weight or BMI. The study confirms French-American differences in personal PS and demonstrates that perceived norms correspond to individual PS.
Keywords: attitudes; culture; food; gender; portion sizes.