Sleeping less than 7 hours may shorten years of your life

The results were recently published in the journal Sleep progress.

National-level data reveal patterns across the United States

To reach their conclusions, the researchers analyzed a large national database, examining survey patterns related to life expectancy across counties across the United States. They compared county-level life expectancy figures with detailed survey data collected by the Centers for Disease Control and Prevention between 2019 and 2025.

When researchers evaluated lifestyle factors associated with how long people lived, sleep emerged clearly. Its association with life expectancy was stronger than its association with diet, physical activity, or social isolation. Smoking was the only factor that showed a greater effect.

“I didn’t expect it to be so strongly associated with life expectancy,” said lead researcher Andrew McHale, Ph.D., an associate professor at the Ohio University College of Nursing, the Ohio University College of Medicine, and the Ohio University Occupational Health Sciences Institute. “We’ve always thought sleep is important, but this research really drives home the point: people should strive to get seven to nine hours of sleep if possible.”

Researchers are surprised by the strength of the results

Much of the work was performed by graduate students in the Sleep, Chronobiology, and Health Laboratory within the Ohio University College of Nursing.

While scientists have long known that adequate sleep supports overall health, the authors said they were still surprised by how close sleep duration is to life expectancy. In the analysis, insufficient sleep outperforms diet and exercise as a predictor of life expectancy.

“It’s very intuitive and logical, but it was amazing to see it so strongly embodied in all of these models,” McHale said. “I’m a sleep physiologist and I understand the health benefits of sleep, but the strength of the link between sleep adequacy and life expectancy was fascinating to me.”

The first study to track annual trends on a state-by-state basis

Previous studies have linked lack of sleep to an increased risk of death, but this research is the first of its kind to show annual correlations between sleep and life expectancy in every US state. For their models, the researchers used the Centers for Disease Control and Prevention (CDC) definition of adequate sleep of at least seven hours per night, which is consistent with recommendations from the American Academy of Sleep Medicine and the Sleep Research Society.

In almost all states and every year analyzed, the data showed a clear relationship between sleep duration and life expectancy.

Why might sleep affect longevity?

The study did not examine the biological reasons behind this association. However, McHale noted that sleep plays a critical role in heart health, immune function and brain performance.

“This research shows that we need to prioritize sleep at least as much as we do what we eat or how we exercise,” he said. “Sometimes, we think of sleep as something we can put aside and maybe put off until later or on the weekend.

“Getting a good night’s sleep will improve how you feel and how long you live.”

Study authors and funding

In addition to McHale, the research team included lead author Katherine E. McAuliffe, BA, Madeline R. Warry, BA, and Gemma V.

Funding for the study came from the National Heart, Lung, and Blood Institute of the National Institutes of Health under award numbers R01HL156948, R01HL169317, and T32HL083808; Ohio University College of Nursing; and the Oregon Institute of Occupational Health Sciences through support from the Oregon Department of Consumer and Business Services (ORS 656.630).