Research

Hormonal

Short sleep duration (habitual or acute) is associated with reduced serum leptin and elevated serum ghrelin, which likely increases appetite and contributes to increased body mass index (BMI).

If you are struggling with weight management or excessive hunger, prioritize getting 7-8 hours of sleep. Short sleep (less than 7 hours) biologically increases your hunger hormones (ghrelin) and decreases your fullness hormones (leptin), making it significantly harder to resist high-calorie foods. Fixing your sleep schedule is a foundational step before expecting diet changes to stick.

GoodSupportsHIGH confidence
Participants with short sleep had reduced leptin and elevated ghrelin. These differences in leptin and ghrelin are likely to increase appetite, possibly explaining the increased BMI observed with short sleep duration.
Shahrad Taheri et al. · PLoS Medicine · 2004

Why this rating

Large population-based sample (n=1,024), controlled for confounders (age, sex, BMI, SDB), but cross-sectional design limits causal inference regarding long-term weight gain.

Source

Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index

Shahrad Taheri et al. · PLoS Medicine · 2004

DOI 10.1371/journal.pmed.0010062

cross_sectional · n=1024Cited 2,464×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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