Study shows that getting more or less sleep has negative effects on cognition and mental health (Image: unplash)
Sleeping seven hours a night is the ideal amount for a middle-aged person. This is the finding of a survey conducted in the United Kingdom that evaluated nearly 500,000 adults between the ages of 38 and 73.
According to the study, sleeping too much or too little is associated with poorer cognitive performance and mental health, including an increased risk of anxiety and depression. Professor Barbara Sahakian, from the University of Cambridge’s Department of Psychiatry, said: “It is very clear that the processes that occur in our brain during sleep are very important for maintaining our physical and mental health.” “For every hour you go away from seven hours, it gets worse,” he adds.
The expert added that a good night’s sleep is essential in all stages of life, but takes on greater importance as people get older: “I think it is just as important as exercise,” according to the British newspaper. Watchman.
The effect of 7 hours of sleep
To conduct the study, the researchers used information from Biobank, the UK’s largest biomedical database, and included brain images and genetic data from nearly 40,000 participants.
The scientists found that the area of the brain most affected by sleep was the area containing the hippocampus, the memory center – where too much or too little sleep is associated with smaller brain size.
A possible cause of the link between insufficient sleep and cognitive decline may be slow-wave or deep sleep, which has been shown to be important for memory consolidation. Lack of deep sleep can prevent the brain from effectively removing toxins.
Another finding from the analysis was that people who slept seven hours each night performed better, on average, on cognitive tests of processing speed, visual attention, memory, and problem-solving skills.
As the Guardian report notes, scientists have been less clear about why eight or more hours of sleep causes problems. One explanation is that sleep deprived and restless people tend to spend more time sleeping — or trying to sleep — because they feel tired.
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Charlotte Whitmore is a contributor at Mediarunsearch.co.uk, covering a broad range of topics including news, politics, business, technology, sport, entertainment, and lifestyle. She focuses on delivering clear, balanced reporting and practical information that helps readers stay informed about current events and emerging developments. Her work highlights stories that matter to everyday audiences, with an emphasis on accuracy, relevance, and accessible journalism that keeps readers connected to the issues shaping the UK and beyond.