Certain objectively measured daytime napping behaviors are associated with an increased risk of mortality for middle-to-older aged adults. Results of a study presented at the SLEEP 2025 annual meeting showed that the median nap duration was 0.40 hours per day.

Thirty-four percent of naps were taken between 9 am and 11 am; 10% were taken between 11 am and 1 pm; 14% were taken between 1 pm and 3 pm; 19% were taken between 3 pm and 5 pm; and 22% were taken between 5 pm and 7 pm. An analysis found that longer naps, greater variability in daytime nap duration, and higher percentages of naps around noon and in the early afternoon are associated with greater mortality risks.

The study sample comprised 86,565 non-shiftworking participants in the UK Biobank with an average baseline age of 63 years; 57% were women. They were monitored by actigraphy for seven days, and daytime napping was defined as sleep between 9 am and 7 pm.

A total of 5,189 (6.0%) participants died during a follow-up period of up to 11 years. Results were adjusted for potential confounders including demographics, body mass index, smoking, alcohol consumption, and nighttime sleep duration.

The American Academy of Sleep Medicine encourages healthy adults to limit naps to no longer than 20-30 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 performance benefits of a nap.

To download the presentation abstract, published in a supplement in the journal SLEEP, click here