March 8, 2013
This weekend, most of us Americans will lose an hour of sleep when we push the clocks ahead to swing into Daylight Saving Time.
That may not seem like much–the Academy Awards were three and a half times that long–but research suggests our bodies wouldn’t agree. A recent study by two Michigan hospitals found that they treated almost twice as many heart attack victims on the first day of Daylight Saving than on a typical Sunday. And if past behavior holds true, there will be a bump in traffic accidents on Monday because, as researchers have suggested, more people take “microsleeps” that day, due to the disruption of their body clocks.
Clearly sleep, or lack thereof, is a key component of psychic and physiological balance, although it wasn’t all that long ago that most scientists felt it wasn’t worth a lot of attention because frankly, it didn’t seem like all that much was going on. Now we know better–there’s a lot happening inside our brains and, apparently, our bodies, too when we’re snoozing.
Unfortunately, that hasn’t made us act much smarter when it comes to our sleeping habits. We’ve been hearing for years that our bodies need a good eight hours a night, but, according to a Centers for Disease Control report released last year, almost a third of working adults in America get only six.
So as David Randall, author of Dreamland: Adventures in the Strange Science of Sleep, noted in a Wall Street Journal column, we’re seeing a boom in sleep aids, energy drinks, expensive mattresses designed to help us find our right “sleep number”, sleep-tracking devices and “fatigue management consultants.” That’s right, fatigue management consultants. A lot of Fortune 500 companies are now using them to track how sleep habits are affecting employee performance and safety records.
When cells go bad
Most of us are painfully aware of the mental and emotional costs of cheating ourselves of sleep. Who among us hasn’t felt the stupidness of fuzzy brain? The physical effects, though, are harder to distinguish. There’s plenty of research now that links poor sleeping habits to obesity, diabetes, heart disease and high blood pressure. But they develop over time–which would seem to suggest that it would take years of bad sleeping to damage our health.
Sadly, that doesn’t seem to be the case. A study just published in the journal Proceedings of the National Academy of Sciences found that getting too little little sleep just a few nights in a row can disrupt hundreds of genes, including those tied to stress and fighting diseases.
Scientists at the Surrey University Sleep Research Center in England subjected 26 volunteers–men and women between the ages of 23 and 31–to two very different weeks of sleeping. One week they were permitted to stay in bed only six hours each night. The other week they were allowed to sleep as long as 10 hours every night. Then the researchers analyzed cells in the volunteers’ blood, focusing on changes in RNA, the molecule that carries out DNA instructions through the body.
What they found surprised them. They discovered that not getting enough sleep changed the patterns in the way genes turned on and off. Overall, 711 genes were expressed differently when people were sleep-deprived: 444 genes were suppressed, 267 were stirred up. And the ones that became more active were genes involved in inflammation, immunity and protein damage.
Plus, when sleeping time was limited to six hours, the genes that govern the body clocks of the volunteers changed dramatically. Almost 400 genes stopped cycling in a circadian rhythm altogether, a disruption that could throw sleep patterns even more out of whack.
Not even Derk-Jan Dijk, the director of the Surrey sleep center, expected to see that. “The surprise for us,” he said, “was that a relatively modest difference in sleep duration leads to these kinds of changes. It’s an indication that sleep disruption or sleep restriction is doing more than just making you tired.”
You snooze, you don’t lose
In honor of National Sleep Awareness Week, which ends Sunday, here are six other recent sleep studies of which you might want to be aware:
- One man’s pizza is another man’s slice: A study at Uppsala University in Sweden determined that men who were sleep-deprived invariably chose larger portions of food than they did when they had a good night’s sleep.
- So that’s why my pillow hurts my head: According to research at the Henry Ford Hospital in Detroit, not getting enough sleep can lower your tolerance for pain. Volunteers who were allowed to sleep nine hours a night for four nights were able to hold their fingers to a source of heat 25 percent longer than study participants who weren’t permitted to sleep more than seven hours.
- Now that’s a vicious cycle: Meanwhile, at the University of California, Berkeley, scientists said they’ve found a clear link between aging brains, the poor sleep of elderly people and memory loss. After comparing the brains and memory skills of young study participants and older ones, the researchers determined that age-related brain deterioration contributes to poor sleep and that leads to memory problems.
- But wait, there’s more bad news: And in Norway, analysis of the medical histories of more than 50,000 people showed that people who said they had trouble falling asleep or remaining asleep were three times more likely to develop heart failure than those who reported no trouble sleeping.
- If only they could sleep right through it: Research from Harvard Medical School suggests that nursing home residents who take sleep aids, such as Ambien, are more likely to fall and break a hip than residents who aren’t taking any meds for insomnia.
- Did I mention that it makes you stupid about food?: Finally, two studies last year showed why sleep deprivation can lead to excess pounds. One discovered that lack of sleep can prompt bad decisions about what food to eat. The other study found that when subjects were permitted to sleep for only four hours, the reward section of their brains became more active when they were shown pictures of pizza and candy.
Video bonus: Here’s a recent ABC News piece on why bad sleep leads to bad memory.
Video bonus bonus: Okay, after all this grim science news, the least I can do is share an oldie-but-goodie stop motion clip of real fun in bed. Sleep tight.
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