THE ESSENTIAL
- Sleep is crucial for many biological functions.
- It is particularly involved in memory, learning and immunity.
Everyone has of course their own rhythm and their own needs, but researchers have just established that sleeping seven hours a night would be the optimum time for our body to function properly.
Performances cognitives
Their study, published in Nature Aging, is gigantic, since it gathered and analyzed the data of 500,000 people between the ages of 38 and 73. Participants were asked about the length and quality of their nights, their mental health and their general well-being. They also took part in a series of cognitive tests.
By cross-referencing all this information, the scientists found that insufficient or excessive sleep duration was associated with impaired cognitive performance, such as analysis speed, visual attention, memory and problem-solving abilities. .
Mental Health
People who slept more or less than 7 hours a night also suffered more from anxiety and depression, feeling worse overall than the others. During the evaluation, it also appeared that the regularity of the nights of sleep was as important as their duration.
Professor Jianfeng Feng, from Fudan University in China, said of his research: “although we cannot say conclusively that too much or too little sleep leads to cognitive problems, our analysis over a long period of time supports this. The reasons why older people sleep less well seem more complex , influenced by our genetic heritage and the structure of our brain.”