Regular napping linked to larger brain volume

woman napping Daytime napping may help to preserve brain health by slowing the rate at which our brains shrink as we age, suggests a new study led by researchers at UCL and the University of the Republic in Uruguay. The study, published in the journal Sleep Health , analysed data from people aged 40 to 69 and found a causal link between habitual napping and larger total brain volume - a marker of good brain health linked to a lower risk of dementia and other diseases. Senior author Dr Victoria Garfield (MRC Unit for Lifelong Health & Ageing at UCL) said: "Our findings suggest that, for some people, short daytime naps may be a part of the puzzle that could help preserve the health of the brain as we get older." Previous research has shown that napping has cognitive benefits, with people who have had a short nap performing better in cognitive tests in the hours afterwards than counterparts who did not nap. The new study aimed to establish if there was a causal relationship between daytime napping and brain health. Using a technique called Mendelian randomisation, they looked at 97 snippets of DNA thought to determine people's likelihood of habitual napping. They compared measures of brain health and cognition of people who are more genetically "programmed" to nap with counterparts who did not have these genetic variants, using data from 378,932 people from the UK Biobank study, and found that, overall, people predetermined to nap had a larger total brain volume. The research team estimated that the average difference in brain volume between people programmed to be habitual nappers and those who were not was equivalent to 2.6 to 6.5 years of ageing.