Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index.
Level 3 - non-randomized controlled study
Cross-sectional analysis within a population-based cohort study
PubMed 15602591 · doi:10.1371/journal.pmed.0010062
What was done
Researchers analyzed 1,024 participants from the Wisconsin Sleep Cohort Study. Subjects underwent overnight laboratory polysomnography and reported their sleep habits through questionnaires and sleep diaries. Morning fasting blood samples were collected following polysomnography to measure serum leptin, ghrelin, adiponectin, insulin, glucose, and lipid profiles. Multiple variable regression models evaluated relationships between sleep duration, body mass index (BMI), and metabolic hormones after adjusting for confounding factors.
What was found
A U-shaped curvilinear association was observed between sleep duration and BMI. Among participants sleeping less than 8 hours (74.4% of the cohort), increased BMI was proportional to decreased sleep. Independent of BMI, short sleep was significantly associated with lower leptin (p for slope = 0.01; predicted 15.5% lower leptin for 5 hours versus 8 hours of habitual sleep) and higher ghrelin (p for slope = 0.008; predicted 14.9% higher ghrelin for 5 hours versus 8 hours of polysomnographic sleep).
Why it matters
This paper identifies a plausible hormonal mechanism linking short sleep duration to obesity in a large population sample, showing that sleep curtailment correlates with reciprocal shifts in appetite-regulating hormones that promote hunger.
Limits
The reported associations are cross-sectional, preventing causal determination between hormone changes and long-term weight gain. Polysomnography reflects only a single night of sleep, and the abstract does not report direct measurements of caloric intake or energy expenditure.
Cited by
- supports Stanford University studies show that sleeping for only 5 hours increases ghrelin by approximately 15%.
- supports Sleeping for only 5 hours decreases leptin by approximately 15%.