The fact that sleep, on top of being critical for well-being, is also one of the best ways for people to escape from the realities of life is why so many people enjoy it, but did you also know that humans are the only mammals who willfully put off going to sleep?

All other mammals respect the value of sleep for overall health and do not allow it to be harmed. Although species have different sleeping habits, all mammals and the majority of other animals need to get some rest.

After discovering that the practice appears to be linked to a larger brain volume, researchers have proposed that taking a brief nap during the day may help to protect the health of the brain as it ages.

While earlier studies indicated that long naps might be an early sign of Alzheimer’s disease, more recent studies have shown that a quick nap can actually help people learn.

According to researchers, there is no evidence that suggests taking naps may help prevent brain shrinkage.

According to The Guardian, the researchers note that this is significant because cognitive impairment and neurodegenerative diseases are associated with an accelerated rate of brain shrinkage, a natural process associated with ageing, and some research suggests that this may be related to sleep issues.

“In line with these studies, we found an association between habitual daytime napping and larger total brain volume, which could suggest that napping regularly provides some protection against neurodegeneration through compensating for poor sleep,” the researchers note.

According to the research published in the journal Sleep Health, researchers from UCL and the University of the Republic in Uruguay describe how they used data from the UK Biobank study, which compiled genetic, lifestyle, and health information from 500,000 people who were 40 to 69 at recruitment.

The team examined whether a collection of genetic variations previously linked to self-reported habitual daytime napping are also connected to brain volume, cognition, and other aspects of brain health using information from 35,080 Biobank participants.

The method enables researchers to probe the relationship between napping and the brain by minimising the impact of lifestyle factors, such as smoking or physical activity, that can affect people’s napping habits and brain health. Such variants are set at birth and are assumed to be randomly assigned.

“It is like a natural randomised control trial,” said Dr Victoria Garfield, a co-author of the study from University College London, adding that the variants were quite common. “They’re present in at least 1% of the population, which is actually quite a lot of people.”

Although it initially appeared that participants who said they rarely or never took a nap during the day had larger total brain volumes, the team discovered the opposite relationship when genetic predisposition to napping was taken into account, suggesting the initial finding may have been due to other factors that muddled the relationship between a nap during the day and brain size.

However, despite the lack of a correlation with cognitive abilities like reaction times, the team did find a connection between a genetic propensity for routine daytime naps and a larger brain volume, equivalent to 2.6 to 6.5 fewer years of ageing.

“It could be having a short daytime nap… could help preserve brain volume, and that’s a positive thing, potentially, [for] dementia prevention,” said Garfield, adding that previous research suggested a duration of up to 30 minutes may be beneficial.

Additionally, the study only used data from white British people, and it is unclear what length of the nap is specifically linked to the advantages. It is also uncertain whether those without a predisposition to napping would experience the same advantages.