Sleeping too much or too little is linked to poorer cognitive performance and mental health starting in middle age, according to a new study. But the important thing is to find your own pace
The ideal hours of sleep? Seven hours, at least starting from middle age. In this way, better cognitive performance would be guaranteed. So concludes new research just published in Nature Aging by a team of Anglo-Chinese researchers.
Sleep changes with age
Il sleepwhich changes with age, plays a important role in activating the cognitive function and in maintaining good psychological health. It also helps keep the brain healthy by removing waste products. As we age, we often see alterations in our sleep patterns, including difficulty falling asleep and staying asleep with a consequent decrease in the amount and quality of sleep. Many scientific studies suggest that these sleep disturbances may contribute to cognitive decline and psychiatric disorders in the aging population. however, it is known that in advanced age sleep changes, becomes more fragmented and fragile, deep sleep decreases but this is physiological: at 80 you cannot sleep as at 20 and it is very frequent to wake up at dawn without being able to fall asleep. .
The seven hours of sleep
In research published in Nature Aging, scientists from the UK and China looked at data from nearly 500,000 adults aged between 38 and 73 years of the British biobank. Participants were interviewed about their sleep patterns, mental health, and physical well-being. They also took part in a series of cognitive tests. Brain imaging and genetic data were also available for nearly 40,000 study participants.
By analyzing this data, the team of researchers found that both insufficient and excessive sleep were associated with impaired cognitive performancesuch as processing speed, visual attention, memory and problem-solving skills.
What then is the optimal amount of sleep to achieve the best cognitive functions? According to the researchers seven hours of sleep a night is the optimal amount of night’s rest for good mental health as well. In fact, it is the volunteers who slept seven hours a night who obtained the best results in cognitive tests. In fact, study participants exhibited more symptoms of anxiety and depression and worse general well-being if they reported sleeping for periods of more than or less than seven hours.
Deep sleep
Researchers say a possible reason for the link between insufficient sleep and cognitive decline could be due toslow wave sleep disruption, deep sleep. in fact it has been shown that the interruption of this type of sleep has a close link with the memory consolidation and the accumulation of amyloid, a key protein that can cause tangles in the brain characteristic of some forms of dementia. Also, lack of sleep can hinder the brain’s ability to rid itself of toxins. Disrupted sleep is associated with increased inflammation, indicating a susceptibility to age-related diseases in older people.
However, scientists are less clear in commenting on why spending eight or more hours in bed could cause problems. One possible explanation that people with disturbed, poor-quality sleep actually tend to stay in bed longer to try to catch up on lost sleep: poor sleep efficiencyi.e. the ratio of actual sleep time to time spent in bed.
Sleep and cognitive decline
The researchers therefore conclude that insufficient or excessive sleep may be a risk factor for cognitive decline in aging. This supported by previous studies that reported a link between sleep duration and the risk of developing Alzheimer’s disease and dementia, in which cognitive decline is a characteristic symptom.
Having a constant seven-hour sleep every night, without too many fluctuations in duration, therefore seems important to achieve valid cognitive performance and good mental health and well-being. Professor Jianfeng Feng of Fudan University in China explained: While we cannot definitively state that too little or too much sleep causes cognitive problems, our analysis that examines individuals over a longer period of time seems to support this idea. But the reasons why older people have poorer sleep appear to be complex, influenced by a combination of our genetic makeup and the structure of our brains.
The teacher Barbara Sahakian of the Department of Psychiatry of the University of Cambridge, among the authors of the study, added: Sleeping well at night is important in all stages of life, but especially with age. Finding ways to improve sleep for older people could be crucial in helping them maintain good mental health and well-being and avoid cognitive decline, particularly for patients with psychiatric disorders and dementias.
How to regulate
What happens if you don’t get seven hours of sleep? In reality, everyone has their own sleep needs. The optimal number of night rest ranges from a minimum of 7 hours for an adult but, for some individuals, even 4-5 hours may be enough without necessarily undergoing lower cognitive performance: they are the short dorms.
The National Sleep Foundation recommends 7-9 hours of sleep for adults aged 26 to 64. For some, even six may be enough (never less), others need 10 (never more). For seniors over 65, 7-8 hours of sleep may be enough, but even then for some, 5-6 hours may be enough, others may need nine.
What matters find your own rhythm, what makes us “work” well during the day, without worrying too much about the 7-8 hour rule which is just a general average. In fact, rest must be synchronized with one’s biological clock: the rhythms of hormones, body temperature, heart rate, pressure and so on must “get along” with that of sleep and with the light / dark cycle.
April 29, 2022 (change April 29, 2022 | 14:31)
© Time.News