You probably know the pull of an afternoon nap. Many of us welcome a quick doze on the sofa, especially after a heavy lunch or a short night's sleep. It feels like a harmless break in the day.
A new 10-year study of 990 older adults tells a less reassuring story.
People who napped most days or every day had a 48 percent higher risk of developing dementia than those who rarely or never napped. The paper was published this month in the Journals of Gerontology: Series A, and all participants were 65 or older.
The team at Johns Hopkins Bloomberg School of Public Health is careful to say the study cannot prove naps cause dementia. The daytime sleepiness itself may be an early sign that something is already changing in the brain.
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Short naps did not get a pass. Napping for 30 minutes or less was linked to a 40 percent higher dementia risk. Falling asleep without meaning to, in a conversation or in front of the TV, carried a 39 percent higher risk.
Why napping may be a marker rather than a cause
The study is observational. That means it can show patterns but not prove what drives them.
The authors point to a two-way relationship between daytime sleep and the aging brain. Changes in the parts of the brain that regulate wakefulness can make a person drowsier during the day, long before memory problems become obvious.
Senior author Adam Spira is a professor at the Bloomberg School. He told Neuroscience News: "More frequent napping could be a marker of changes in the brain, rather than a cause of brain changes that lead to dementia."
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That nuance matters. The signal may be most useful not as a warning about naps themselves, but as a prompt to look more closely at a person's overall sleep and daytime alertness.
What this means for your afternoon doze
An occasional nap on a tiring day is not the point. The study looked at how often, how long, and how intentionally older adults slept during the day.
The sharpest signal was for people who napped nearly every day, and for those who kept falling asleep when they did not plan to.
If you or someone you care about has started dozing off most days, or struggling to stay awake through meals or conversations, that is worth mentioning at the next check-up.
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The researchers suggest that tracking napping habits could help doctors spot older adults who may need a closer look at their sleep and memory, according to Medical Xpress.
The study drew on the National Health and Aging Trends Study, a nationally representative group of older Medicare beneficiaries followed from 2013 through 2023. Over that decade, 417 of the 990 adults went on to develop possible or probable dementia.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.