Abstract
BACKGROUND: Weekend-weekday differences in time of ingestive events may be implicated in adverse metabolic and health outcomes. However, little is known about the nature of weekend-weekday differences in temporal eating behaviors of the US adult population. OBJECTIVE: The study aimed to examine weekend-weekday differences in temporal and energy characteristics of ingestive events self-reported by American adults. DESIGN: Observational; within-person comparative. PARTICIPANTS/SETTING: The data were from the National Health and Nutrition Examination Surveys (NHANES) 2015-March 2020 (pre-pandemic) for ≥20-year-old adults who provided 1 weekday (M-Th) and 1 weekend (F, S, Su) 24-h dietary recall (n = 3564 men and 3823 women). MAIN OUTCOME MEASURES: Prespecified primary temporal outcomes were recalled: time of ingestive events, and the duration of ingestive and fasting windows. Secondary outcomes included frequency and energy characteristics of ingestive events. STATISTICAL ANALYSIS PERFORMED: Gender-specific, survey-weighted, multiple linear regression models that accounted for complex survey design with dummy covariates for weekend/weekday, mode of recall administration (in-person on day 1 and telephone on day 2), and a respondent-specific fixed intercept. RESULTS: In both men and women, the weekend recalled time of first ingestive event, breakfast, and lunch were later than weekday (P ≤ .0008); however, no statistically significant differences were observed in time of dinner and the last eating episode. The mean weekend ingestive window (interval between the time of first and last eating events of the day) was shorter by 24 minutes (95% confidence interval [CI], -32, -11) in men and 18 minutes (95% CI, -20, -15) in women, and the mean overnight fasting window was correspondingly longer (P ≤ .0001). No statistically significant differences were observed between weekend and weekday frequency of ingestive events. Energy density of weekend food selections reported by women, and of beverages by men, was found to be higher than weekday (P ≤ .002). CONCLUSIONS: Weekend ingestive patterns were characterized by later time of first ingestive event, breakfast, and lunch, and selection of higher-energy-density foods and beverages.