Sleep is essential for all of us and there is no doubt related to it. Sleep is essential because when you sleep it helps to repair your body, lower the risk of health problems like diabetes and heart diseases, and is good for your mental health.
If a person sleeps properly, this can also reduce the risk of Alzheimer’s disease. And, if you are not sleeping enough, this is linked to cognitive decline.
According to a recent study by the researchers of the Washington University School of Medicine, getting too little sleep or sleeping too much may also be linked with cognitive decline.
The researchers wanted to know more about the link between sleep and cognitive impairment over time and therefore they tracked 100 older adults (middle-age adults and adults in their late 70s) for four to five years.
During the study, 12 people showed signs of cognitive impairment (one with mild dementia and 11 with the pre-dementia stage of mild cognitive impairment). The rest of the 88 people did not show any signs of dementia. In this study, participants were told to complete neuropsychological tests and some commonplace cognitive tests, so that the researchers get their scores, and after combining the participant’s scores into a single score, they understood their cognition over a period of time.
To measure sleep the researchers used a single-electrode encephalography (EEG) device. This device helps to measure the brain activity of the participants to measure how restful that sleep was and for long. This device is worn on the forehead and is used three years after the participants complete their annual cognitive tests.
It can be disturbing for a few days for the participants to get used to the EEG device on their forehead while sleeping but after a few days, they are comfortable with it. The sleep was measured at one period during the study, but still, it was helpful for the researchers to get the needed measurements and to monitor their participants’ sleep habits.
The research also looked into other factors that can lead to cognitive declines like genetics, signs of protein beta-amyloid or tau and age.
So, came out of this research?
The researchers found that if a person is sleeping for more than 6.5 hours and less than 4.5 hours and their sleep quality is not good this can be associated with cognitive decline over a period of time. However, the impact of sleep on the participants during the cognitive function was similar to the effect of age and this is the biggest risk related to cognitive decline.
Researchers still do not know for sure why lack of sleep can lead to cognitive decline. One theory says that when you sleep it helps to flush out the harmful proteins that further build up during the daytime like beta-amyloid and tau that can increase due to sleep deprivation. Even if you sleep-deprived for one night this can increase the beta-amyloid levels temporarily in the brain.
It is still not clear why long sleep hours is linked with cognitive decline because as per some previous studies there are some links found between oversleeping and cognitive performance. The reason there is still not a clear picture regarding the link between your sleeping hours and cognitive decline is that the studies most relied on the participants self-reporting on how long they sleep every night and this means the data is not accurate compared to the EEG research that has more weight to such findings.
According to the study, sleeping for more than 6.5 hours is associated with cognitive decline over a period of time, and this is low if we consider that older people are advised to get 7 to 8 hours of sleep every night.
Therefore, it is not about the length of time of the sleep, but what matters is the quality of your sleep, when it comes to the risk of dementia. And, something that is still not clear from the study is that long sleep duration can independently predict cognitive decline. It is not easy to see that those participants who slept for more than 6.5 hours at night didn’t have pre-existing cognitive problems of brain changes suggestive of dementia that was not found in the tests.
There are other factors as well that might not be contributed during the study and that might be linked to cognitive declines like physical activity level, poor health and socioeconomics status. Therefore, you can say that there are other factors that can decline your sleep quality and lead to cognitive decline. There are some factors that are not preventable like genetic predisposition, but there are things that can be helpful to prevent cognitive decline like a healthy diet, exercising, mental health and your lifestyle.
However, as the research of this study seems to suggest there’s an optional sleep duration-between .5 and 6.5 hours every night- the occasional weekend lie-in is unlikely to do your brain any harm.
Today, many people face sleep deprivation due to poor lifestyle habits, unbalanced meals and uncertain timing of sleep and meal. Therefore, it is essential to change a few lifestyle habits that can make a drastic change to your overall health and sleep quality. It is not about hours, but it is more about your sleep quality.
Babies know best when it comes to sleeping, that helps them to grow stronger both physically and mentally. Lack of good sleep also happens because of a sedentary lifestyle where people do not do enough exercise, physical activity and follow unhealthy food habits and uncertain meal time.
This type of lifestyle can also hamper your sleep quality. It is advisable for people who lack a good night sleep, to fix their sleep time and have an early dinner to avoid any issues while sleeping. Fixing your sleep time can be really beneficial for your sleep, just like fixing meal time helps in the better absorption of nutrition.
So, the next time you feel like not sleeping, remember one thing, you should make your lifestyle so physically active that when you go to bed, you are simply dead. Even if you are lying on a rock, you are able to sleep like a baby. So, make sure you follow some small-small steps to improve your physical and mental health, and you will realize that your sleep quality will also improve.