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Sleep Week
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Evidence library

Every claim, with its source attached.

Sleep Week measures sleep using research from sleep science, body-clock biology and behavior change. We hold our own writing to the same standard we use for guest data. Each statistic lists its definition, population, place, year, source and any caveat.

Citations

Sources used across this site.

Methodology

How to read our survey data.

2024 National Health Interview Survey (NHIS)

A nationally representative survey of U.S. households. Sleep questions cover the past 30 days or usual duration and are self-reported. Estimates are weighted; small subgroups carry more uncertainty.

2022 Behavioral Risk Factor Surveillance System (BRFSS)

A state-based phone survey of adults. Short sleep means fewer than 7 hours in 24 hours. State estimates are age-adjusted and can't be compared directly with the national NHIS numbers.

Not getting enough sleep is linked to higher risk of obesity, type 2 diabetes, high blood pressure, heart disease, stroke, anxiety and depression. Poor sleep is one visible sign that something in the body is out of balance. This link doesn't prove poor sleep directly causes those problems. The relationship often runs both ways and other factors play a role.

Statistics register

The full list.

Statistics register with source and verification data
StatisticPopulationGeographyYearSourceVerified
30.5% of U.S. adults averaged fewer than seven hours of sleepAdults aged 18 and overUnited States2024Centers for Disease Control and Prevention2026-07-26
15.4% had trouble falling asleep most days or every dayAdults aged 18 and overUnited States2024Centers for Disease Control and Prevention2026-07-26
18.1% had trouble staying asleep most days or every dayAdults aged 18 and overUnited States2024Centers for Disease Control and Prevention2026-07-26
54.8% usually woke feeling well-restedAdults aged 18 and overUnited States2024Centers for Disease Control and Prevention2026-07-26
12.9% used a sleep aid most days or every dayAdults aged 18 and overUnited States2024Centers for Disease Control and Prevention2026-07-26
35.2% of California adults reported insufficient sleepAdults aged 18 and overCalifornia2022Centers for Disease Control and Prevention2026-07-26

Language standards

Words we use, and words we avoid.

We use

  • Designed to
  • May help
  • Screens for
  • Supports
  • Measures
  • Physician reviewed
  • Subject to clinical review
  • Proposed collaboration
  • Where clinically appropriate

We do not claim

  • Cures insomnia
  • Guaranteed restored recovery
  • Diagnoses all sleep disorders
  • Replaces a sleep study
  • Johns Hopkins-approved
  • Medical-grade, unless that exact product and use is approved for it
  • Clinically proven, unless a study backs that exact claim
  • FDA approved, unless that specific product has that approval
  • HIPAA compliant, unless our setup has been reviewed to meet that standard
Clinical guardrails