Research

Energy balance

Higher Body Mass Index (BMI) has a putative causal effect on increased daytime sleepiness, as determined by Mendelian Randomization analysis.

If you are overweight, your increased daytime sleepiness may be biologically driven by your BMI, not just your habits. Weight management strategies may help reduce sleepiness, but be aware that the relationship is causal and may require addressing metabolic or circadian dysfunction.

GoodSupportsMEDIUM confidence
Using the inverse variance weighted (IVW) approach, we identified a putative causal association of higher BMI with increased daytime sleepiness (IVW β = 0.018; 95% CI [0.008, 0.028]; P = 0.0004).
Heming Wang et al. · Nature Communications · 2019

Why this rating

Large sample size and use of MR to infer causality, though sensitivity analyses showed heterogeneity.

Source

Genome-wide association analysis of self-reported daytime sleepiness identifies 42 loci that suggest biological subtypes

Heming Wang et al. · Nature Communications · 2019

DOI 10.1038/s41467-019-11456-7

cohort · n=452071Cited 251×
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DOI resolved against Crossref · corpus check 2026-06-10

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