Association between Sleep Duration and Body Composition in Girls Ten to Eighteen Years of Age: A Population-Based Study.

Background: This study aimed to evaluate the relationship between sleep duration and body composition as measured by dual-energy X-ray absorptiometry (DXA). Methods: Based on data obtained from the Korea National Health and Nutrition Examination Survey (2010), 303 girls were divided into three groups by sleep duration: very short, short, and recommended. Results: By analysis of covariance, compared with the "very short" group, the "recommended" group had reduced adjusted mean DXA-assessed total mass (TM, 46.46 kg vs. 51.36 kg, p = 0.012), fat mass (FM, 14.38 kg vs. 17.55 kg, p = 0.002), and fat mass percentage (FMP, 30.66% vs. 33.15%, p = 0.017) in the whole body; TM (20.85 kg vs. 23.63 kg, p = 0.007), FM (5.82 kg vs. 7.64 kg, p = 0.001), and FMP (27.48% vs. 30.70%, p = 0.009) in the trunk; TM (4.59 kg vs. 5.15 kg, p = 0.006), FM (1.62 kg vs. 2.05 kg, p = 0.001), and FMP (27.48% vs. 30.70%, p = 0.019) in the arms; and TM (16.75 kg vs. 18.23 kg, p = 0.042) and FM (6.09 kg vs. 6.97 kg, p = 0.018) in the legs. By multiple linear regression analysis, sleep duration in hours had a significant negative association with DXA-assessed TM (β = -1.221, p = 0.016) and FM (β = -0.760, p = 0.006) in the whole body; FM (β = -0.014, p = 0.026) in the head; TM (β = -0.699, p = 0.010), FM (β = -0.454, p = 0.003), and FMP (β = -0.714, p = 0.030) in the trunk; TM (β = -0.152, p = 0.005) and FM (β = -0.101, p = 0.004) in the arms; and FM (β = -0.191, p = 0.045) in the legs. Conclusions: Our results suggest that shorter sleep duration is related to higher FM, but not lean mass, especially in the trunk.