Association between circadian rest-activity rhythm and meal timing: NHANES 2013-2014

OBJECTIVES: This study examined the associations between actigraphy-derived rest-activity rhythm and meal timing. It also investigated whether these associations are modified by race/ethnicity. METHODS: We used data from the National Health and Nutrition Examination Survey 2013-2014 (n = 2944). Twenty-four-hour rest-activity metrics (mean, amplitude, acrophase, and robustness) were derived from actigraphy data via cosinor analysis. Continuous meal-timing exposures were mean-centered (weighted means) so that coefficients represented associations within the reference race/ethnicity group (Non-Hispanic White) at the sample mean. Models included race × meal-timing interaction terms to test whether associations between meal timing and acrophase differed by race/ethnicity. Significant interactions were further examined using race-stratified simple slopes, with β-estimates, standard errors, and 95% confidence intervals reported. RESULTS: Significant interactions were observed for acrophase and last mealtime (P-interaction = .02). Later last meals were associated with later acrophase among Mexican American (β = 0.77 ± 0.28, p-interaction = 0.02) and Non-Hispanic Black (β = 0.40 ± 0.12, p-interaction = 0.02) adults. No other exposure-outcome pairs were significant (P > .05). CONCLUSIONS: Significant race/ethnicity interactions indicate that Mexican American and Black adults with later last meals exhibited correspondingly later acrophase compared with White adults. Our findings suggest possible associations between meal timing and acrophase varying by race. These findings highlight potential racial/ethnic differences in circadian responses to meal timing, underscoring the need for culturally tailored measures in circadian nutrition research.