Research

Energy balance

Both short (5-6 hours) and long (9-10 hours) sleep durations predict increased body weight and fat gain compared to average sleep (7-8 hours) over a 6-year period.

Aim for 7-8 hours of sleep per night. Both sleeping significantly less (5-6 hours) and significantly more (9-10 hours) is associated with greater weight and fat gain over time. Prioritize sleep consistency and duration as a key factor in weight management, independent of diet and exercise.

GoodSupportsHIGH confidence
This study provides evidence that both short and long sleeping times predict an increased risk of future body weight and fat gain in adults.
Jean‐Philippe Chaput et al. · SLEEP · 2008

Why this rating

Longitudinal design with objective adiposity measures and adjustment for multiple covariates, though limited by self-reported sleep and sample size.

Source

The Association Between Sleep Duration and Weight Gain in Adults: A 6-Year Prospective Study from the Quebec Family Study

Jean‐Philippe Chaput et al. · SLEEP · 2008

DOI 10.1093/sleep/31.4.517

cohort · n=276Cited 389×
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DOI resolved against Crossref · corpus check 2026-06-10

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