Is shortened sleep duration a risk factor for overweight and obesity during adolescence? A review of the empirical literature.

This paper reviews 15 adolescent (10-19 yrs) studies that have directly investigated the effects of shortened sleep duration on overweight and obesity. The research studies included in this review inconsistently found significant effects between shortened sleep duration and weight status. This heterogeneity in study findings largely resulted from variability in study design, gender, and the method used to measure sleep duration. Consequently, due to the conflicting research findings, it remains inconclusive as to whether shortened sleep is a risk factor for overweight or obesity during adolescence. This review also identified methodological limitations within the literature and presented alternative methodologies for future research. First, sleep duration measures were identified that had questionable reliability and were possibly less accurate than other recommended sleep measurements. Second, 92% of cross-sectional studies found a significant relationship, yet 0% of prospective studies did. Third, the vast majority of studies neglected to statistically adjust for co-contributions from depression, and approximately half of the studies considered the role of physical activity. Recommendations for future research directions are presented which may help to clarify the conflicting findings and address the methodological concerns identified within this topical area.