Sleep duration might not be the first thing you associate with heart disease. However, there has been an increasing amount of research done recently with regards to the potential causality between the length and quality of our sleep and cardiovascular illness.
The ever-increasing pace of the modern lifestyle has made sleep deprivation a common condition in developed countries. As people have been sleeping less and less, more and more studies have been conducted on the effects of inadequate sleep duration on health and quality of life. Within this process another important point has been noted – oversleeping is just as detrimental.
So, how much is too much and what is the threshold below which you shouldn’t go?
Sleep deprivation increases the risk of heart disease.
Sleep deprivation, or deficiency, includes not getting enough sleep, breaking the body’s circadian rhythm, or not getting enough quality and undisturbed sleep. In the United States, only 44% of people report sleeping enough on a regular basis.
Everyone is familiar with the immediate effects of sleep deficiency. But what may seem like short-term energy deprivation can contribute to neurological and psychological disorders in the long run . The increased sympathetic nervous system activity caused by sleep deprivation disturbs the regular physiological processes of the body .
In addition to this, sleep deficiency has been associated with significant, long-lasting changes to the body causing heightened predisposition to cardiovascular disease .
Oversleeping’s not much better.
The harmful effects of oversleeping had been frequently understated up until recently.
The Journal of the American Heart Association published a meta-analysis earlier this year. The researchers reported a higher likelihood of cardiovascular disease in people who deviated from the recommended sleeping period of 7 to 8 hours. Surprisingly, they found a higher risk with oversleeping in comparison to sleeping less than the recommended amount. As well, poor sleep quality was linked to significantly increased risk of coronary heart disease regardless of the duration .
In a study conducted in middle-aged and older Chinese, even midday napping lead to higher risks of coronary heart disease, particularly in individuals with normal weight and without diabetes. They concluded that sleeping > 10 hours or napping > 90 minutes increased the risk of coronary heart disease by as much as 25-33% .
The Golden Mean
While optimal sleep duration does vary between individuals based on a number of factors, for most healthy adults 7 to 9 hours is considered appropriate. For majority of older adults, 7 to 8 hours is the optimal sleep duration. Slightly more or less hours of sleep is acceptable, but habitual and excessive sleep deprivation or oversleeping can either contribute to health issues or worsen your existing problems .
While the rhythm of modern society might pose some challenges, research increasingly confirms that prioritizing self-care and proactively adjusting your sleeping habits can make a great difference to your health and well-being.
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 Yang L, Yang H, He M, et al. Longer Sleep Duration and Midday Napping Are Associated with a Higher Risk of CHD Incidence in Middle-Aged and Older Chinese: the Dongfeng-Tongji Cohort Study. Sleep vol. 39,3 645-52. 1 Mar. 2016, doi:10.5665/sleep.5544
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