Research

Energy balance

Shorter self-reported sleep duration is associated with higher BMI and waist circumference in adult women, but this association is attenuated and becomes non-significant when physical activity levels are controlled for.

For women, getting less sleep is linked to higher body fat and waist size, but this link seems to happen because less sleep leads to less physical activity, not just direct metabolic changes. If you sleep less, you may be too tired to move as much. Prioritizing sleep might help maintain the energy levels needed for physical activity, which is the stronger driver of body composition in this context.

ModerateQualifiesMEDIUM confidence
In women, the inverse association between sleep duration and BMI was significant after controlling for age and race (β = −0.294, P = .005) and other lifestyle and physiologic variables (β = −0.294, P = .005). However, after physical activity was added to the model, the association between sleep and BMI became nonsignificant (β = −0.172, P = .084).
Marie‐Pierre St‐Onge et al. · International Journal of Endocrinology · 2009

Why this rating

Observational cohort study with large sample size but reliance on self-reported sleep data and cross-sectional design limits causal inference.

Source

Gender Differences in the Association between Sleep Duration and Body Composition: The Cardia Study

Marie‐Pierre St‐Onge et al. · International Journal of Endocrinology · 2009

DOI 10.1155/2010/726071

cross_sectional · n=3473Cited 79×
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DOI resolved against Crossref · corpus check 2026-06-10

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