Cambridge/Shanghai (dpa) – Seven hours of sleep is the ideal amount of sleep for middle-aged and older people. This was reported by American and Chinese scientists in the journal “Nature Aging”.
The conclusion of the study is that significantly more or less sleep is associated with poorer mental health and poorer mental performance. Good sleep is the most important, especially for the elderly.
Specifically, scientists from the universities of Cambridge and Fohan examined data on nearly 500,000 adults aged 38 to 73 collected in the “UK Biobank”, a comprehensive British database. Participants were asked about their sleep patterns, mental health and wellness, and also took part in a series of cognitive tests. MRI images of the brain and genetic data were available to nearly 40,000 participants.
Not too short and not too long
An analysis of all this information showed that both too little sleep and too much sleep were associated with lower cognitive performance – the corresponding subjects were slower on tests, had shorter attention spans and poorer problem-solving skills. Their mental health was affected, too: People who slept too much or slept too little showed more symptoms of anxiety, depression, and lower overall well-being.
Researchers believe that disrupted slow-wave sleep, which is part of deep sleep, could be a possible cause of cognitive decline. Such a disorder is associated with the accumulation of beta-amyloid particles. These protein deposits, which are found in large clumps in the brains of Alzheimer’s patients, are suspected of contributing to the death of neurons.
Analysis of brain scans also revealed an association between different sleep periods and differences in the structure of brain regions involved in cognitive processing and memory. Among them was the hippocampus, which is considered the brain’s memory center.
Perfect for cognitive performance
Overall, the researchers concluded that seven hours of uninterrupted sleep appears to be optimal for cognitive performance, general well-being, and mental health in middle-aged and older people. Although the study did not describe causation, the results indicated that insufficient or excessive sleep duration could be a risk factor for cognitive decline in old age.
Author Jianfeng Feng asserts in a statement: “While we cannot definitively say that too little or too much sleep causes cognitive problems, our analysis, which looks at people over a longer period of time, appears to support this idea.” However, the reasons older adults sleep poorly appear to be complex, and involve a combination of genes and brain structure.
Barbara Sahakian, a neuropsychologist and co-author, adds that good sleep is important throughout life, but especially as we age: “Finding ways to improve sleep for older adults can be critical in helping them improve their mental health and well-being and Avoid cognitive decline, especially in patients with psychiatric disorders and dementia.”
Difficulty sleeping through the night and napping during the day
In fact, according to the German Society for Sleep Research and Sleep Medicine (DGSM), elderly people especially often report sleep problems, lower total sleep time, more daytime naps, and increased use of sleeping pills. However, sleep difficulties are increasingly being identified across age groups and throughout the world.
In Germany alone, a third of those surveyed in a 2017 Techniker-Krankenkasse study complained of sleep problems, and everyone else said they slept no more than six hours. According to guidelines from the US National Sleep Foundation (NSF), the duration should be seven to nine hours for adults. However, their authors stress that the need for sleep varies from person to person.
© dpa-infocom, dpa: 220502-99-123991 / 4