Research

Mixed

Sleep duration is primarily determined by environmental factors with low heritability, whereas body composition measures (adiposity and lean mass) are strongly influenced by genetic factors with high heritability.

You cannot change your genetic predisposition to body fat or lean mass, which accounts for a large portion of your body composition. However, sleep duration is largely environmentally determined, meaning you have significant control over how much you sleep. This suggests that improving sleep habits is a viable lever for health, even if it doesn't directly dictate your genetic body type.

GoodSupportsHIGH confidence
The heritability of sleep duration was 0.27 in men and 0.29 in women, while the heritability of body composition was as high as 0.56–0.73 after adjustment for age in both genders. Sleep duration was largely influenced by environmental factors while adiposity measures were mainly influenced by genetic factors.
Rong Liu et al. · Obesity · 2011

Why this rating

Uses a cotwin design (MZ and DZ twins) which is a robust method for estimating heritability, controlling for shared environment and genetics.

Source

A Population‐Based Twin Study on Sleep Duration and Body Composition

Rong Liu et al. · Obesity · 2011

DOI 10.1038/oby.2011.274

cross_sectional · n=1249Cited 27×
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DOI resolved against Crossref · corpus check 2026-06-10

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