According to a study led by University College London (UCL) and published in the journal Sleep Health, regular daytime napping may prevent brain shrinkage in later life.
The research involved nearly 380,000 participants from the UK Biobank research database.
Findings revealed that middle-aged individuals predisposed to napping had larger brains, indicating better brain health, with a difference equivalent to 2.6 to 6.5 years of aging, The Times reported.
Dr Victoria Garfield, senior author from the Medical Research Council (MRC) unit for Lifelong Health and Ageing at UCL, said that short daytime naps may contribute to preserving brain health as people age.
The study utilised a technique called Mendelian randomization, comparing genetically inclined nappers with non-nappers to establish a causal link.
The nappers exhibited a larger total brain volume.
The study’s genetic variants influencing napping were identified through questionnaires and data from devices like Fitbit.
The researchers found consistent results even when excluding variants associated with excessive daytime sleepiness.
Although the study explored brain changes and performance, it did not observe differences in hippocampal volume, reaction time, or visual processing among genetically predisposed nappers.
However, according to Garfield there may be other brain structures linked to daytime napping that future studies could investigate.
Research suggests that one in seven adults between 26 and 64 regularly take naps, while almost one-third of individuals aged 65 and above engage in napping.
Short siestas of less than 30 minutes are increasingly supported by scientists as a means to boost productivity and overall health, offering immediate cognitive benefits and reduced sleepiness for up to three hours.
However, longer naps, exceeding 30 minutes, may have less favourable effects, including a higher risk of obesity, high blood pressure, and diabetes.
Most studies indicate that the strongest benefits are associated with napping in the early afternoon.
While establishing a causal relationship between napping and brain health has been challenging, the latest study’s analytical approach, examining genetic factors rather than self-reported behaviour, adds confidence to the notion that daytime sleep can impact the brain.
