Insufficient sleep is the second-strongest behavioral predictor of life expectancy in the United States, trailing only smoking, according to a study published in December 2025 in the journal Sleep Advances. Researchers at the Oregon Health & Science University (OHSU) Sleep, Chronobiology, and Health Laboratory found that regularly getting less than seven hours of sleep per night correlates with a shorter lifespan, cutting across geographic and socioeconomic lines.
Analysis of 3,143 US Counties Connects Sleep Duration to Mortality
The OHSU team analyzed data gathered between 2019 and 2025 through the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System (BRFSS). By examining monthly telephone survey responses across all 3,143 counties in the United States, the researchers mapped local health behaviors against life expectancy outcomes. The resulting dataset stands as one of the most comprehensive local-level analyses of sleep duration ever conducted.
To establish risk hierarchies, lead author Andrew McHill and his colleagues evaluated multiple lifestyle factors side by side. The models accounted for physical inactivity, food insecurity, unemployment, educational attainment, health insurance status, and social integration. The team set the insufficient sleep threshold at less than seven hours per 24-hour period, following guidelines from the American Academy of Sleep Medicine and the Sleep Research Society.
Statistical Modeling Ranks Insufficient Sleep Just Behind Smoking
When researchers ran statistical models incorporating all behavioral variables simultaneously, smoking emerged as the primary behavioral predictor of life expectancy with a coefficient of minus 0.31. Insufficient sleep ranked second, registering a coefficient of minus 0.17. Physical inactivity and poor diet demonstrated weaker correlations in the primary model.
A secondary model incorporated obesity and diabetes—conditions that function simultaneously as causes and consequences of chronic sleep deprivation. Even with these clinical factors factored into the analysis, the inverse relationship between short sleep duration and lower life expectancy remained statistically significant.
McHill stated that he had not expected insufficient sleep to correlate so strongly with life expectancy, adding that while sleep’s importance has always been known, this research emphasizes that.
Geographic Consistency Across US States
The correlation between short sleep and reduced life expectancy proved consistent across nearly every US jurisdiction. In 2025, all but three states exhibited this statistically significant association. Longitudinal data showed similar stability: 84 percent of states displayed the pattern in 2019, while 100 percent showed it by 2024.
State-level reviews, such as those conducted in Oregon, demonstrated that counties with lower proportions of short sleepers systematically reported higher life expectancy averages than counties where inadequate sleep was more prevalent.
Methodological Scope and Limitations
Because the investigation relied on an observational design, researchers cannot establish direct causation showing that sleep deprivation independently strips years from a human life. The BRFSS dataset does not track variables like shift work schedules, diagnosed sleep disorders including sleep apnea, or underlying psychiatric conditions.
The survey also groups all individuals sleeping seven hours or more into a single category. This means healthy sleepers are pooled alongside long sleepers, a demographic also associated with elevated health risks. Researchers noted that isolating healthy sleep durations from excessive sleep would likely sharpen the observed negative association with short sleep.
Although the COVID-19 pandemic altered sleep routines globally through lockdowns and lifestyle disruptions, the statistical link between inadequate sleep and reduced longevity remained stable across the pandemic years.
Implications for Public Health Policy
Study authors emphasize that breaking down health metrics to the county level allows public health officials to deploy targeted local interventions. Because sleep duration acts as a modifiable behavior that functions independently of household income, insurance coverage, or urban versus rural residence, officials can address it in populations where access to specialized healthcare or fresh food is constrained.
McHill noted that this research shows that we must prioritize sleep at least as much as diet or exercise. A good night improves not only well-being, but also life expectancy.
The research received funding support from the National Institutes of Health and Oregon Health & Science University. Public access to the underlying metrics is available via the County Health Rankings portal.
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