Comparing Two Days of Dietary Intake in What We Eat in America (WWEIA), NHANES, 2013–2016

The objective of this research is to compare the Day 1 and Day 2 dietary intakes of adults in What We Eat in America, National Health and Nutrition Examination Survey (WWEIA, NHANES) 2013–2016. Dietary recalls of males (n = 2599) and females (n = 2624) 20+ years who had both a Day 1 and Day 2 recall and reported their intake as usual on both days in WWEIA, NHANES 2013–2016 were examined. Mean (±SE) energy intake for males was 2425 ± 26 kcal for Day 1 and 2334 ± 32 kcal for Day 2 (p = 0.004). For females, 1832 ± 18 kcal and 1775 ± 26 kcal were reported for Day 1 and 2, respectively (p = 0.020). There were no significant differences between energy intake on Day 1 and Day 2 within males and females by ten-year age groups. Comparing 20 year age groups for males and females by race/ethnicity (non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic) and income (350% of poverty level) also showed no significant differences in energy intake between Day 1 and Day 2. Mean energy intake of adults was not statistically different between the two days of recall by sex, race/ethnicity or income within selected age groups. Overall, the difference in energy intake was less than 4% for both males and females.