Association of diurnal calorie trajectory with all-cause mortality: Findings from the National Health and Nutrition Examination Survey

Background & aims The effect of diurnal variation in energy intake on mortality has not been reported. We investigated the effect of diurnal calorie trajectory on all-cause mortality using data from the National Health and Nutrition Examination Survey (NHANES). Methods Participants in the NHANES from 1999 to 2010 were analyzed. We calculated daily energy intake and the two-hourly calorie intake according to dietary interview questionnaires, in which timing of meals, as well as energy and nutritional components of each food were recorded. The daily energy intake and the two-hourly calorie intake were divided by body weight to determine tertiles of daily energy intake and diurnal calorie trajectories, respectively. Three diurnal calorie trajectories (reference group, excess dinner, and high-calorie) were identified. The mortality data were linked to the National Death Index through the end of 2011. Cox proportional hazards models were used to compare the overall mortality among different groups. Results Among the 14,356 participants included in our analyses, 886 (6.2%) of them died after a median follow-up of 4.4 years. Daily energy intake tertiles were not associated with all-cause mortality in the fully adjusted model. In contrast, high-calorie trajectory was associated with a higher risk of mortality (hazard ratio 3.128, 95% CI 1.175 to 8.330, p = 0.024) compared with the reference group after adjustment for relevant factors. Conclusions A diurnal high-calorie trajectory was associated with a higher risk of mortality, compared with the reference group. The effect of a large evening meal on mortality merits further investigation.