Overview
- OHSU researchers reporting in SLEEP Advances found insufficient sleep was more strongly associated with reduced U.S. life expectancy than poor diet, low exercise or loneliness, trailing only smoking.
- The team compared county-level life expectancy with CDC survey data from 2019–2025, using a threshold of at least seven hours per night as sufficient sleep.
- Mechanistic research underscores why sleep matters, with deep sleep supporting glymphatic clearance of brain waste and a 2025 Neurology study tying weak or irregular circadian rhythms to markedly higher dementia risk.
- WHO estimates about 40% of people worldwide sleep poorly, with experts pointing to long or unpredictable work hours, hyperconnectivity and irregular schedules as major drivers.
- Very short sleep latency—falling asleep in under five minutes—is flagged by sleep experts as a sign of severe sleep debt, and brief pre-bed techniques like slow breathing and consistent routines can ease sleep onset.