Short daytime naps could keep the brain healthy, scientists say

IS taking a nap good for your health or not? It's a vast subject that has given rise to a host of scientific studies, some of them contradictory, but all of which attempt to determine the benefits of this short snooze typically taken after lunch.

The latest study examines the benefits of napping on cognitive function and brain volume. And the results could encourage many to adopt this typically Mediterranean lifestyle habit.

Some people struggle to fall asleep after a busy day, tossing and turning in bed unable to drop off, while others are able to doze anywhere, anytime, just by closing their eyes, even if only for a few minutes.

According to a new study conducted by researchers at University College London (UCL) and the Universidad de la Republica de Montevideo, Uruguay, the latter may be more alert as they age thanks to these brief periods of sleep, which appear to play a role in brain health.

Published in the journal Sleep Health, the research is based on a large panel of 35,080 people aged between 40 and 69, drawn from UK Biobank data.

The researchers first analysed participant responses as to how often they napped during the day – regularly, sometimes, rarely or never – and then verified them via sleep trackers.

Their genetic profile was then established using data from previous studies. The scientists used this data to determine which people napped regularly based on 92 genetic differences, and then looked at their brain size.

And the results are surprising, to say the least. In particular, they suggest that the brain volume of people who regularly indulge in the art of napping is greater (15.80 cm3 on average), compared with those who get little or no shut-eye during the day.

Assuming that the brain declines, or shrinks, by 0.2% to 0.5% per year from the age of 35 onwards, the researchers estimate that regular nappers could benefit from a brain that is 2.6 to 6.5 years younger.

The scientists added: "This difference approximately equates to the difference in brain volume between people with normal cognitive function and mild cognitive impairment."

Note, however, that the researchers refer to "short naps" without specifying the duration or frequency with which people should indulge in these daytime siestas to reap real benefits.

Still, the study confirms that regular rest periods of this kind should ultimately help preserve brain health, while reaffirming that benefits are apparent after a nap of 5 to 15 minutes.

A previous scientific study, conducted by researchers at Brigham and Women's Hospital and published in April, revealed that taking long naps can be detrimental to health.

It's precisely naps lasting longer than 30 minutes that reportedly increase the risk of obesity, high blood pressure and metabolic syndrome. Napping, therefore, seems to be beneficial to health, provided you don't sleep for too long. – ETX Daily Up, June 21, 2023