Napping isn't just a sign of fatigue. The timing and duration of naps may also be a predictor of mortality in middle-aged and older adults, according to a recent study presented at the conference. SLEEP 2025, but not yet published in a scientific journal. Analysis of the naps of more than 86,000 people who were not on night shifts, and therefore active during the day, showed that long naps, with variable duration or taken around midday and early afternoon, were associated with an increased risk of mortality.
Among the 86,565 people included in the cohort, the average age was 63 years at the start of the study. 57% of the participants were women. They were monitored for seven days using an actigraph, a watch-like device designed to assess sleep-wake cycles. The median duration of naps was 24 minutes per day. Most of them (34%) were taken between 9 and 11 a.m. 10% took place during the lunch hour (between 11 a.m. and 1 p.m.), 14% in the early afternoon (between 1 p.m. and 3 p.m.). In the second half of the day, 19% naps were taken between 3 p.m. and 5 p.m. Then 22% at the very end of the day, between 5 p.m. and 7 p.m. Overall, with age, naps tended to become longer and more irregular, with the schedule shifting toward the afternoon. During a follow-up of up to 11 years, 6% of the participants (5,189) died.
Three types of naps at risk“
To truly measure the effect of napping on health, without confounding it with other factors such as BMI (body mass index), smoking, alcohol consumption, or even the duration of nighttime sleep, the calculations were adjusted to take these possible influences into account. Three major trends emerged from this work: longer nap duration, greater variability in nap rhythm, and naps taken between 11 a.m. and 3 p.m. were associated with increased mortality.
“ This is an observational study. What we found are associations, not direct causes. In short, we cannot conclude that napping has a direct influence on health or mortality.", warns Science and Future Dr. Chenlu Gao, a researcher specializing in circadian rhythms at Harvard University (USA) and author of the publication. Similarly, it cannot be said that changing the way you nap will improve your health or mortality risk. We need more studies to better understand this topic.. »
So it's not napping itself that deteriorates health to the point of increasing the risk of mortality. But napping appears to be a good indicator of overall health, or at least of its decline. Long daytime naps may reflect poor nighttime sleep due to underlying cardiovascular, pulmonary, neurodegenerative, or mental health conditions. All of these conditions increase the risk of mortality, especially if they are not addressed.
Read alsoHere's How Lack of Sleep Damages Neurons and Blood Vessels
Detect underlying pathologies
In chronic heart failure, the heart is no longer able to pump blood efficiently. At night, this results in a feeling of shortness of breath, causing waking up, as well as frequent urges to urinate at night. COPD (chronic obstructive pulmonary disease), it obstructs the airways and causes the oxygen level in the blood to drop. At night, micro-awakenings and general agitation disrupt sleep.sleep apnea also causes repeated respiratory arrests during the night which deteriorate sleep and cause fatigue. The same goes for the restless legs syndrome, which generates movements that delay falling asleep or interrupt nighttime sleep.
The study authors therefore recommend that the topic of naps be routinely addressed during general practitioner consultations so that the patient's overall sleep is studied, and not just how the nights unfold.
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