Most of us have accepted this as a rule: for adults, a full night’s sleep means eight hours. However, this may not be the case when people reach a certain age.
A team of researchers from the University of Cambridge in the UK and Fudan University in China have found that seven hours of sleep may be the ideal time to close your eyes for middle-aged and older people.
In a study published in the journal The aging of natureThe researchers found that seven hours of sleep was good for cognitive performance and good mental health.
Researchers studied data from nearly 500,000 participants between the ages of 38 and 73 and found that insufficient but also excessive sleep was associated with impaired cognitive function and poor mental health.
The study participants talked about their sleep patterns and answered questions about their health and mental health. They performed a series of cognitive tasks that tested speed of development, visual attention, memory, and problem-solving skills. Those who slept seven hours a night were better off.
However, there is one caveat: 94% of the participants were white, so it is unclear whether the results are correct for people of color and other ethnic or cultural backgrounds.
Another important factor is consistency. The best results were observed in people who showed a slight fluctuation in sleep for a long time and adhered to it for seven hours.
In other words, four hours of sleep in front of a large congregation is not enough to “think” about 10 hours of sleep the next night.
Interrupted sleep: Risk of dementia
“A good night’s sleep is important at all stages of life, but especially as we get older,” says Barbara Sahakyan, a professor at Cambridge University and co-author of the study.
Researchers say that sleep deprivation can interfere with the brain’s ability to rid itself of toxins. They also say that slow waves or deep sleep disorders may be responsible for cognitive decline.
When deep sleep is disturbed, it affects the consolidation of memory and can lead to the accumulation of amyloid, a protein that, if it fails to function, can create “confusion” in the brain that is characteristic of some types of dementia.
Inadequate or excessive sleep can be a risk factor for cognitive decline in old age.
“While we can’t say for sure that too much or too little sleep causes cognitive problems, our analysis seems to support this idea,” said Jiangfeng Feng, a professor at Fudan University. “However, the causes of poor sleep in older people appear to be complex, and are 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 looked at brain images and genetic data, but these data were only available to less than 40,000 participants.
These data suggest that the amount of sleep may be due to differences in the structure of brain regions, such as the hippocampus, which is considered the brain’s memory and learning center, and the precentral cortex, which is responsible for performing voluntary movements.
Because Alzheimer’s and the risk of mental disorders – aging disorders associated with cognitive impairment – are linked to sleep duration, researchers say more work needs to be done in the field of sleep science.
“Finding ways to improve sleep in older people can be important to help them maintain good mental health and well-being. [their] Avoid cognitive decline, especially for patients with psychiatric disorders and dementia, ”Sahakyan said.
Edited by Zulfikar Abbani