A new study linking daytime napping to increased mortality rates in older adults may prompt reevaluation of midday naps. The study, presented at SLEEP 2025, found that frequent, longer, and irregular daytime naps — especially in the early afternoon — were linked to a higher risk of death over an eight-year period.
“Our study fills a gap in knowledge,” said lead author Chenlu Gao, a postdoctoral research fellow at Massachusetts General Hospital in Boston. The research shows “not just whether someone naps, but how long, how variable, and when they nap during the day may be meaningful indicators of future health risk,” Gao added.
The study included 86,565 participants, averaging 63 years of age, who worked regular daytime schedules. Scientists defined daytime napping as sleeping between 9 a.m. and 7 p.m. After the initial study, researchers monitored participants for eight years and found that 5,189 (6.0%) of them died during that time.
Results were adjusted for other potential factors influencing mortality, such as demographics, weight, smoking, alcohol consumption, and nighttime sleep duration. “Naps are not necessarily problematic unless they are used to compensate for chronically poor sleep at night,” said Dr. Chelsie Rohrscheib, a neuroscientist and sleep specialist at Wesper in New York.
“Getting seven to nine hours of good quality sleep is required to maintain health and reduce the risk of developing dangerous medical conditions like heart disease and diabetes,” added Rohrscheib, who was not involved in the study. However, the study did not establish proof that naps directly affect the risk of death.
“These are associations,” Gao said. “We cannot conclude from this study whether napping causes poor health.” The study relied on detecting movement but not brain activity, which may have misclassified “quiet wakefulness” as sleep. Additionally, defining daytime napping as sleep between 9 a.m. and 7 p.m. could have mistakenly included participants’ actual sleep, affecting the accuracy of what would count as a nap.
Excessive napping could also be a marker of other health issues, such as chronic disease, systemic inflammation, or disruptions to circadian rhythms, which may themselves increase mortality risk. “Someone who requires daily naps to get through the day is likely not getting sufficient sleep during the night, or has an underlying health condition that causes daytime sleepiness,” Rohrscheib noted.
Gao added, “We need more research to understand the causal relationships before we can conclude that a certain type of napping pattern would benefit health.” “However, we suggest that monitoring napping patterns might help us identify health conditions early, so that we can implement interventions accordingly.” The American Academy of Sleep Medicine encourages healthy adults to limit naps to no longer than 20 to 30 minutes in the early afternoon.
While a brief “power nap” can improve daytime alertness and performance, naps of 30 minutes or longer may cause a person to feel groggy after waking up. This grogginess, or “sleep inertia,” can delay the short-term benefits of a nap, experts say.
Overall, the findings suggest that when it comes to mid-day snoozing, moderation is key — and that napping patterns could be a window into broader health concerns worth discussing with a medical provider.