Posted Mar 16, 2010
THE idea that we need less sleep as we get older is a myth, according to researchers.
A study has found that the middle aged and elderly need just as much as the young if they want to keep a clear head the next day.
However, they are more likely to suffer from an interrupted night’s sleep because of health problems – forcing them to adapt by catnapping, or coping with tiredness in the day, the research showed.
The findings contradict the long established belief that the amount of sleep we need falls as we approach middle and old age.
Dr Sean Drummond, a psychologist at the University of California, San Diego, said: ‘It’s a fallacy. The quantity of sleep that we need does not go down as we age, but the ability to sleep in one chunk does get lost.’ According to the sleep researchers, most people need between seven and nine hours every day.
One in 20 needs more than nine hours, while one in 50 can cope happily on fewer than six hours.
Dr Drummond tested the impact of sleep on 62 volunteers in the laboratory.
They included a group of young people, with an average age of 27, and a set with an average age of 68. Both groups spent two nights in the lab as scientists monitored their sleep patterns.
On the second day they were asked to memorise a list of words while their brains were monitored to see how efficiently they were working.
Dr Drummond, who reported his findings at the American Association for the Advancement of Science conference in San Diego, found that the performance of both groups was strongly linked to the previous night’s sleep.
However, for the older group, it was the amount of sleep they got that had a ‘significant influence’ on brain function the following day, Dr Drummond found.
‘The more sleep last night, the more efficient brain function is today and the better they are able to learn and remember new material,’ he said.
‘Whereas in young adults, the amount of sleep they get isn’t so important.’ What matters more is that sleep is consolidated into a solid chunk, allowing the brain to act as ‘a dry sponge, ready to absorb and learn new information’.
Dr Drummond said older people need as much time in bed as the young but often they simply get used to having less.
‘The biggest, most common, most robust change is that we spend more time awake in the middle of the night as we get older,’ he added.
d.derbyshire@dailymail.co.uk
Date: Feb 23, 2010