How many hours of sleep you regularly get can impact how long you live.
Getting a full night of sleep may be more important for longevity than most people realize.
Research from Oregon Health & Science University shows that regularly getting too little sleep is linked to a shorter lifespan.
To reach their conclusions, researchers analyzed a large national database, looking at survey patterns related to life expectancy across counties in the U.S.
They compared county-level life expectancy figures with detailed survey data collected by the Centers for Disease Control and Prevention (CDC) between 2019 and 2025.
When the team evaluated lifestyle factors tied to lifespan, sleep stood out.
Its link to life expectancy was stronger than diet, physical activity or social isolation.
- Smoking was the only factor that showed a bigger effect.
Researchers Surprised by the Strength of the Findings
Much of the work was done by graduate students in the Sleep, Chronobiology and Health Laboratory at OHSU.
While scientists have long known that adequate sleep supports overall health, the authors were struck by how closely sleep duration tracked with life expectancy.
It was startling to discover that insufficient sleep outweighed diet and exercise as a predictor of lifespan.
The paper noted that the association was “remarkable.”
Tracking Yearly Trends Across States
Previous studies have linked poor sleep to higher risk of death, but this research is the first to show year-by-year connections between sleep and life expectancy across every U.S. state.
For their models, researchers used the CDC definition of sufficient sleep as at least seven hours per night, which aligns with recommendations from the American Academy of Sleep Medicine and the Sleep Research Society.
Across nearly all states and every year analyzed, the data showed a clear relationship: The more people sleep, the longer they tend to live.
Why Sleep Impacts Longevity
The study didn’t investigate the biological reasons for this link, but the team noted that sleep greatly impacts heart health, immune function and brain performance.
The team says that sleep should be prioritized as much as “what we eat or how we exercise.”
Many people view sleep as something to put off or catch up on.
To them, it just doesn’t seem as important as a plate of fresh greens or an hour at the gym.
The research unconvered the striking association but did not probe deeper for cause and effect.
So this leaves the door open for the possibility that, for example, genes that aren’t of the longevity type might also be genes that prevent consistent longer sleep.
Or perhaps whatever it is that makes people die short of the average life expectancy also prevents restful sleep beyond six hours.
Maybe those who average six or fewer hours of sleep do so because of ongoing stress and anxiety — which can shorten lifespan by encouraging unhealthy habits such as smoking, drinking, a poor diet and avoiding exercise.
Ongoing stress and anxiety can also cause physiological changes in the body that aren’t conducive to living a long life.
These observations aside, common sense tells us that averaging only six or fewer hours of sleep a night just isn’t enough to fully recharge the body and brain.
The findings were published in the journal SLEEP Advances (2025).
