Eight hours of sleep has long been the golden rule for a good night’s rest. But researchers from China and the UK now say older people need less sleep.
Most of us have mastered this rule: A full night of sleep means eight hours for adults. But this may not be true anymore, as people reach a certain age.
A team of researchers from the University of Cambridge in the UK and Fudan University in China found that seven hours of sleep may be the ideal sleep time for middle-aged and older people.
In a study published in the journal Nature Aging, researchers said that seven hours of sleep was the most ideal for mental health.
Study participants reported their sleep behaviors and also answered questions about their well-being and mental health. They underwent a series of exercises related to cognitive skills, which tested their speed of information processing, visual attention, memory, and problem-solving skills. Those who had had seven hours of uninterrupted sleep did better.
However, one thing needs to be clarified: 94% of the participants were white, so it is unclear whether the results are true for people of color and other ethnic or cultural backgrounds.
Another important factor is sustainability. The best results were seen in people who showed only slight fluctuations in their sleep routine for long periods of time and who were faithful to the seven-hour period.
Interrupted sleep: risk of dementia
“Getting a good night’s sleep is important at all stages of life, but especially as we get older,” said Barbara Sahakian, a professor at Cambridge University and co-author of the study.
The researchers said that lack of sleep is likely to hinder the brain process to rid itself of toxins. They also say that a slow or deep sleep disruption may be responsible for the deterioration of cognitive abilities.
Deep sleep disturbance affects memory impairment and this can lead to the accumulation of amyloid, a protein that – if not functioning properly – can cause “confusion” in the brain, thus leading to dementia.
Insufficient or excessive sleep can be a risk factor for brain aging.
“We can not say for sure that too little sleep or too much sleep causes problems with cognitive abilities,” said Jianfeng Feng, a brain researcher and professor at Fudan University. influenced by a combination of our genetic makeup and the structure of our brain. ”
The duration of sleep affects the structure of the brain
The researchers also analyzed brain images and genetic data, but those data were only available to less than 40,000 participants.
These data showed that the amount of sleep may be related to changes in the structure of brain regions such as the hippocampus, which is considered the center of memory and learning in the brain, and the precentral cortex, which is responsible for performing voluntary movements.
Since the risk of Alzheimer’s and dementia – age-related diseases with impaired cognitive ability – is linked to sleep duration, researchers said further work in the field of sleep science is essential.
“Finding ways to improve sleep for older people can be crucial in helping them maintain good mental health and well-being and avoid cognitive decline, especially for patients with psychiatric disorders,” Sahakian said./DW