February 25, 2017 0348 GMT
It can prevent your brain from aging and help you perform better in memory tests, express.co.uk wrote.
But it has to be for 60 minutes. A longer or shorter siesta will not have the same effect.
Researchers at the American Health in Aging Foundation examined 3,000 adults over the age of 65.
They found those who slept for an hour in the afternoon were better able to solve simple maths problems, copy geometrical figures and memories words.
Those who did not take a nap performed badly in the tests.
The researchers said: “These people experienced about the same decline in their mental abilities that a five-year increase in age would be expected to cause.”
They added: “Cognitive function was significantly associated with napping.
“Moderate nappers had better overall cognition than non-nappers or extended nappers. Non-nappers also had significantly poorer cognition than short nappers.”
Sleep has already been identified as a weapon in the fight against Alzheimer’s. Sleeping soundly can help control levels of the brain toxin peptide betaamyloid.
Consultant psychiatrist Dr. Sylvia Tang said: “Sleep is so important for restorative functions, including memory, and now it looks like having a siesta, especially if you are older, may have medicinal purposes.
“You must sleep some time between lunch and dinner, and no halfway measures.
“Other studies have suggested daytime nappers can also improve their heart health, because napping lowers their blood pressure.
“It is fascinating to see, though, that about an hour is the optimum time and not longer. It appears that to re-boot your brain an hour is all it takes, even as you age.”
Dr. Paul McLaren, medical director of the Priory hospital in Hayes Grove, Kent, said: “Siestas are well established in European culture and there is probably a very good reason why these things have become established rituals.
“As we get older, our sleep patterns get more fragmented. An afternoon nap can be invigorating and is good for preventing brain ageing.”
David Eaton, of the International Longevity Centre UK, added: “This new study suggested that naps between 30 and 90 minutes, forming part of a regular regime of 7-8 hours sleep per day, may help some people enjoy the benefits of greater cognitive and physical health in later life.
“Studies have also shown that those living past 85 maintain stricter sleeping and napping patterns, which appear good for them.”
Dr. David Reynolds, chief scientific officer at Alzheimer’s Research UK, said: “This study adds to growing evidence that sleep has a beneficial impact on learning and memory.
“Sleep disturbances are common in Alzheimer’s. It’s important for future research to delve deeper into the science behind sleep and cognition, to shed light on those sleep patterns that may hold the most benefit for our brain health as we age.”
Meanwhile a separate study found pensioners who become more active reduce their risk of ill-health, and of heart disease in particular.
The more exercise they do the greater the protection, but even a short walk round the living room is enough to reduce the risk.
Researchers analyzed 2,465 men and women aged 65 to 74 who participated in a national health study conducted between 1997 and 2007 in Finland.
Professor Noel Barengo, of the Florida International University, said: “Walking has been found to be associated with lower risk of mortality.
“Even occasional activity reduces the risk. If you become more active — even by taking several short walks round your home each day — you can improve your health significantly and lower your risk of heart disease.”