Seven hours of sleep each night is the ideal amount in middle to old age, research suggests.
“For every hour that you moved away from seven hours, you got worse. It’s very clear that the processes that go on in our brain during sleep are very important for maintaining our physical and mental health” says Professor Barbara Sahakian.
Getting a good night’s sleep, she added, was important at all stages of life, but particularly as people aged. “I think it is as important as getting exercise.”
The study of nearly 500,000 adults aged between 38 and 73 found that both too much and too little sleep were linked with worse cognitive performance and mental health, including anxiety and depression. A consistent amount of sleep also appeared to be beneficial.
The study is available here: Li, Y., Sahakian, B.J., Kang, J. et al. The brain structure and genetic mechanisms underlying the nonlinear association between sleep duration, cognition and mental health. Nat Aging (2022). https://doi.org/10.1038/s43587-022-00210-2