Figure 1. Average portion size and energy density per eating occasion, by food and beverage.

Data on PS (A) and ED (B) are from cross-sectional nationally representative samples of adults (≥19 y) taken from NFCS 1977–78 (n = 17,464), CSFII 1989–91 (n = 8,340) and 1994–98 (n = 9,460), and NHANES 2003–06 (n = 9,490), standardized to the age, gender, and race/ethnic distribution of the sample in 1977–78.