In middle and old age, a study shows that seven hours of sleep every night are ideal


According to studies, persons in their middle years and older should get seven hours of sleep per night, with too little or too much sleep being linked to worse mental and cognitive functioning.

Sleep is crucial for maintaining psychological health and enabling cognitive function. It also helps the brain stay healthy by getting rid of trash. As we age, our sleep patterns frequently change, and we experience issues with falling and staying asleep as well as decreasing quantity and quality of sleep. It is believed that these sleep abnormalities may be a factor in the ageing population’s cognitive decline and psychiatric illnesses.

In a study that was just published in Nature Aging, researchers from the UK and China looked at information from almost 500,000 persons in the UK Biobank who were between the ages of 38 and 73. A battery of cognitive tests and questions regarding participants’ sleep habits and mental health and wellbeing were also administered. Nearly 40,000 study participants had genetic and brain imaging data available.

The team’s analysis of these data revealed that poor sleep quality and quantity were both linked to a decline in cognitive abilities like processing speed, visual attention, memory, and problem-solving abilities. The best amount of sleep for both cognitive function and mental health was seven hours per night, with participants who reported sleeping for longer or shorter periods of time feeling worse overall and experiencing more symptoms of worry and despair.

The disturbance of slow-wave, or “deep,” sleep, the researchers speculate, may be one factor in the link between insufficient sleep and cognitive deterioration. It has been demonstrated that disruption of this type of sleep is closely related to memory consolidation and the accumulation of amyloid, a crucial protein that, when it misfolds, can result in the “tangles” in the brain that are indicative of some types of dementia. Additionally, a lack of sleep may make it harder for the brain to get rid of pollutants.

The research team also discovered a relationship between sleep duration and variations in the structure of brain areas related to cognitive processing and memory, with bigger changes linked to greater or less than seven hours of sleep.

It was also crucial for cognitive function, excellent mental health, and overall wellbeing to get a constant seven hours of sleep every night. Previous research has demonstrated that irregular sleep patterns are linked to increased inflammation, suggesting that older persons are more susceptible to diseases connected with ageing.

While we cannot state with certainty that getting too little or too much sleep causes cognitive issues, our examination of people over a longer period of time seems to corroborate this theory, according to Professor Jianfeng Feng of Fudan University in China. However, the causes of why older individuals sleep worse than younger people seem to be complicated, influenced by both our genetic make-up and the structure of our brains.

The results, according to the researchers, point to a possible risk factor for cognitive deterioration as people age: inadequate or excessive sleep duration. Previous research has suggested a connection between sleep length and the risk of dementia and Alzheimer’s disease, both of which include cognitive loss as a hallmark symptom.

One of the study’s authors, Professor Barbara Sahakian of the University of Cambridge’s Department of Psychiatry, stated: “Getting a good night’s sleep is vital at all stages of life, but particularly as we age. In particular for patients with psychiatric disorders and dementias, finding techniques to promote sleep for older individuals could be vital to helping them maintain excellent mental health and wellbeing and prevent cognitive decline.