Researchers have come up with the perfect rationale for the post-prandial siesta. It seems that napping for an hour or so after lunch improves memory and the ability to think clearly.

A study involving nearly 3,000 older adults recorded participants’ nighttime sleep habits, noted whether they took an afternoon nap and, if so, how long they napped. The scientists then looked at the performance of the study participants on a series of mental status tests that assessed attention and memory, including basic math problems, answering simple questions and drawing common shapes.

According to a report published in the Journal of the American Geriatrics Society, 60 percent of participants reported taking daytime siestas. Those who napped for about an hour after lunch performed significantly better on the cognitive tests than those who did not nap at all, those who napped for 30 minutes or less and those who slept 90 minutes or longer. Although a short nap was found to be better than no nap at all, the cognitive performance among hour-long nappers was up to six times better than that of participants who took no naps, short naps or very long naps.

This article originally appeared in Mind, Mood & Memory, a publication of the Department of Psychiatry at Massachusetts General Hospital dedicated to maintaining mental fitness from middle age and beyond.

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