June 20, 2023 – As we age, the performance of the human brain step by step declines. But a latest study suggests that folks who commonly take short naps in the course of the day can slow this aging process by two to 6 years.
The researchers wrote that “this difference is roughly equivalent to the difference in brain volume between people with normal cognitive function and mild cognitive impairment.”
Published on Monday within the magazine Healthy sleepThe study examined data from 378,932 people aged between 40 and 69. The average age was 57. The people, all from the UK, had previously entered their health and genetic information right into a database called UK Biobank.
Starting at age 35, the brain begins to shrink at a rate of 0.2% per yr, and the speed increases to 0.5% per yr by age 60, the authors noted. They decided to check the consequences of naps on brain volume since the rate of brain shrinkage has been linked to conditions corresponding to Alzheimer's disease, and brain volume has been linked to sleep disorders corresponding to insomnia.
“Our findings suggest that for some people, short daytime naps may be a piece of the puzzle that could help maintain brain health in old age,” said genetic epidemiology researcher Victoria Garfield, PhD, at University College London in a opinion.
The researchers used a fancy method based on an individual's genetic profile to discover individuals who commonly took daytime naps. As a part of their participation in providing data to the UK Biobank, the people collaborating within the study had undergone cognitive tests to evaluate their visual memory and response time. One group of the people collaborating within the study also had brain images from MRI scans stored within the UK Biobank, which the researchers used to analyse the dimensions of the people's brains.
The authors identified that previous studies have shown that daytime naps affect brain health in older people, corresponding to improved performance on cognitive tasks. Some studies have shown that the advantages of naps last for several hours and even an entire day. However, this latest study failed to seek out a link between naps and other people's performance on tests of visual memory and response time. The researchers wrote that they were surprised by this result and suspected that the tests the study participants took could have been flawed.
“I hope that studies like this one, which demonstrate the health benefits of short naps, can help reduce the stigma that still exists around daytime naps,” Garfield said.