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 (NE), is increasing in adults, but rarely studied in younger ages.

Objective
To review the association between later eating rhythm and adiposity in children and adolescents, in terms of energy intake (EI) (EI for evening main meal, evening snack, whole evening period and around bedtime); timing (any food eaten at later timing); and meal frequency (evening main meal skipping, evening snack consumption) in the evening/night.

Data Sources and Data Extraction
Five databases were searched; data extraction and quality assessment were conducted by two reviewers independently.

Results
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 very weak evidence to suggest that consuming evening snacks reduced adiposity (OR 0.80, 95%CI 0.62, 1.05). No association was seen with eating later (OR 1.04, 95%CI 0.68, 1.61). In the narrative analysis, around half of studies suggested no association between later eating rhythm and adiposity as a whole or within exposure subsets.

Conclusions
The magnitude of the relationship between later eating rhythm and adiposity is very small and results may vary according to different aspects of later eating rhythm, however, the evidence is of very low certainty. Further research with a more consistent definition of ‘later timing’ and longitudinal studies in different populations are very likely to have an important impact on our confidence in the estimate of effect, and may change the results.

Systematic Review Registration
PROSPERO registration number CRD42019134187