Many people view daytime napping as a benign, even beneficial habit. However, new research indicates that naps exceeding one hour may pose significant health risks.
"Daytime napping is common worldwide and often seen as healthy," says study lead author Dr. Zhe Pan from Guangzhou Medical University in China. "A widespread belief holds that napping boosts performance and offsets sleep debt. Our findings challenge these assumptions."
Prior studies on napping and risks of mortality or cardiovascular disease yielded mixed results, often overlooking nighttime sleep duration.
This meta-analysis reviewed evidence from over 20 studies involving 313,651 participants, with 39% reporting daytime naps.
Results showed long naps (>60 minutes) linked to a 30% higher all-cause mortality risk and 34% greater cardiovascular disease risk compared to non-nappers. Accounting for nighttime sleep, the mortality risk persisted only for those sleeping over six hours nightly.
Any nap duration correlated with a 19% increased mortality risk, stronger in women (22%) and older adults (17%).
Short naps (<60 minutes) showed no cardiovascular risk. "Shorter naps, especially 30-45 minutes, may benefit heart health for those short on nighttime sleep," notes Dr. Pan.
Mechanisms remain unclear, but long naps may elevate inflammation, blood pressure, diabetes risk, and impair physical health, per related research.
Dr. Pan concludes: "For safest napping, keep it under an hour. No strong evidence supports starting the habit if you don't already nap."
