Research

Adherence

Late bedtimes and late wake-up times are associated with unfavorable weight status and activity patterns in adolescents, independent of sleep duration.

For adolescents, shifting bedtime and wake time later is linked to higher obesity risk, largely due to increased screen time and reduced physical activity, regardless of total sleep hours. Encouraging earlier bedtimes may help reduce sedentary behavior and improve weight status.

ModerateSupportsMEDIUM confidence
late bedtimes and late wake up times are associated with an unfavorable activity and weight status profile, independent of age, sex, household income, geographical remoteness, and sleep duration.
Tim Olds et al. · SLEEP · 2011

Why this rating

Observational cross-sectional study; strong sample size but cannot prove causation.

Source

Sleep Duration or Bedtime? Exploring the Relationship between Sleep Habits and Weight Status and Activity Patterns

Tim Olds et al. · SLEEP · 2011

DOI 10.5665/sleep.1266

cross_sectional · n=2200Cited 255×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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