Nothing beats a good night’s sleep. OK, maybe some fun the night before but, really, several hours of uninterrupted rest is never overrated. Whether you’re catching up from lack of sleep from the week before or are just spending a much-deserved Sunday morning/early afternoon in bed, it can never be too much.
Or can it?
A study from the University of Cambridge found that those who sleep longer than eight hours could increase the risk of a stroke. Researchers also found the risk doubles with seniors who regularly sleep longer than the average eight hours. Yikes.
Because we’re fans of the shuteye, we decided to take a deeper look.
The science is in and sleeping too long may be more harmful to the cardiovascular system than tucking in for a shorter period, says Dr. Marc Leavey, an internist who works out of Mercy Medical Center in Baltimore. Sure, people who sleep for shorter amounts of time (fewer than eight hours) may have an 18 per cent increased risk of stroke, but “those sleeping for prolonged times increased their risk some 46%, which was significant.”
The study, which was published in the medical journal Neurology, followed about 10,000 people between the ages of 42 and 81 for almost a decade and researchers found that close to 70 per cent of those studied reported sleeping six-to-eight hours each night, while 10 per cent slept more than eight hours. Just under 350 participants suffered a stroke during the study period, a fact that’s a little frightening in itself.
No more naps? WHAT??
Bad news for all you folks out there who feel the need to disappear for a little while, close the sun-blocking blinds and shut out the world. The study found that those who took both short or long naps for a four-year period quadrupled (!) their risk of stroke.
But, according to Dr. Nitun Verma, a Stanford-trained sleep doctor who recently went on Reddit to answer questions about sleep, there are circumstances where naps are key. Those who balance wonky hours due to shift work need to take a nap to “improve alertness on the job” while “narcoleptic patients still need scheduled naps, even after medications.” Take that, study!
The light at the end of the tunnel (no, no, not that light)
Leavey, who answers medical questions on his blog, String of Medical Pearls, concedes that while the study presents compelling data, the issue he has is that someone always likes to assign cause and effect — even where it may not exist. He likens the sleep debate to those who feel like the flu shot gives them a cold or the flu. Sleep, in fact, might not be the issue here; rather, an underlying condition might exist and that’s what needs to be addressed.
Dr. Atul Khullar, Medical Director of Northern Alberta Sleep Clinic and senior consultant at Medsleep, concurs. “If you are sleeping consistently more than nine hours a night, there’s something else wrong. I don’t think it’s the excess sleep per se but another issue that needs to be targeted.” He adds that while the research is definitely interesting, the findings for studies like these can be overdramatized.
Upon further study
The researchers at the university admit they don’t understand the exact link between the amount of sleep one gets and having a stroke. They also acknowledge that more studies need to be conducted in order to learn more. Leavey points out that what does deserve further study is a preexisting inflammatory and/or cardiovascular disease in the participants.
If you are sleeping for nine hours or more each night, Leavey says it’s associated with “increased risk of morbidity and mortality” and you should be screened and monitored “for any underlying medical conditions.” Verna concurs, recommending that everyone should “get those 7-9 hours of sleep!” But nothing more, got it?
More than nine hours, bad. And you should probably go get yourself checked out. Seven to nine hours, ideal. But with crazy schedules, overwhelming stress, snoring spouses and early-bird kids, that might be easier said than done.