The association between later eating rhythm and adiposity in children and adolescents: a systematic review and meta-analysis

Context Childhood adiposity, an important predictor of adult chronic disease, has been rising dramatically. Later eating rhythm, termed night eating, is increasing in adults but rarely studied in younger ages. Objective The objective of this study was to review the association between later eating rhythm and adiposity in children and adolescents. The aspects of later eating being considered included: energy intake (for evening main meal, evening snack, whole evening period, and around bedtime); timing (any food eaten at later timing); and meal frequency in the evening/night (evening main meal skipping, evening snack consumption). Data Sources Five databases (the Cochrane Library, CINAHL, Embase, MEDLINE (via OVID), and Web of Science) were searched for eligible articles published prior to and including August 2020. Data Extraction Data extraction and quality assessment were conducted by 2 reviewers independently. Data Analysis Forty-seven studies were included, all of which were observational. Meta-analysis showed positive associations between both higher energy intake around bedtime (odds ratio [OR] 1.19, 95% CI 1.06, 1.33) and evening main meal skipping (OR 1.30, 95% CI 1.14, 1.48), and adiposity. There was evidence to suggest that consuming evening snacks reduced adiposity, but it was very weak (OR 0.80, 95% CI 0.62, 1.05). No association was seen between eating later and adiposity (OR 1.04, 95% CI 0.68, 1.61). In the narrative analysis, approximately half of the studies suggested that there was no association between later eating rhythm and adiposity, either as a whole or within exposure subsets. Conclusion The magnitude of the relationship between later eating rhythm and adiposity is very small, and may vary depending on which aspects of later eating rhythm are under consideration; however, the evidence for this conclusion is of very low certainty. Further research with a more consistent definition of "later timing", and longitudinal studies in different populations, may lead to different conclusions. Systematic Review Registration PROSPERO registration no. CRD42019134187.