- A number of studies have shown that drugs like Ambien and Lunesta offer no significant improvement in the quality of sleep, and they give only slightly more quantity (11 minutes more than a sugar pill). People feel like they slept better because the pills cause “retrograde amnesia”—i.e., they cause you to forget you tossed and turned all night.
- Sleeping pills accounted for more than $1 billion in advertising between 2005-6.
- Cognitive therapy is far more effective than sleeping pills in the long run.
- Until the era of artificial light, it was normal for humans to wake up in the middle of night at roughly the same time. After the “first sleep”, as it was called, people often stayed up for an hour or two—to pray, contemplate, read, have sex, etc—before sinking into a second sleep. Researchers have confirmed that this is indeed a natural sleep pattern, so you may want to think twice before resisting it or medicating for it, especially since it may become the most reliably relaxed hour of your day.
- Studies report that the quality and characteristics (hard or soft) of a mattress are not really correlated to the quality of sleep—despite what you may imagine and what the mattress companies urge you to imagine.
- After the 1994 earthquake knocked out power in Los Angeles, some residents called to report a “giant, silvery cloud” in the sky. It was the Milky Way. Owing to light pollution, two-thirds of people in the United States and Europe cannot see it.
- There is strong evidence of a link between light pollution and diseases. For example, studies have found a significant increase in breast cancer rates for women who live in areas with high levels of light pollution. (In this case, the hypothesis is that light affects levels of meltanonin which may in turn effect production of estrogen.)
- Women snore less and sleep more lightly than men, which is truly one of nature’s cruel jokes.
- In 1993, 1 in 15 parents admitted sharing a bed with their child. In 2007, 1 in 3. It’s likely that the actual number of co-sleepers is considerably higher, since there remains a stigma around the practice.
- One of the most important causes of military accidents such as friendly fire and plane crashes is lack of sleep. Nor are stimulants necessarily an answer; for while they improve confidence in one’s ability, they also lead you to misjudge how well you’re actually performing.
- Athletic performance is adversely affected by lack of quality sleep. To take just one example, researchers found that in NFL games the team that crossed time zones to play another team was significantly more likely to lose.
- And finally, one utterly unsurprising but very important fact. (In fact, I’m nominating it for science’s annals of the obvious.) On days after a poor night’s sleep, your “emotional climate” is worse. For example, how women slept the night before was a better predictor of how happy their interactions were than whether it was a hard day at work, or other forms of stress.
Hat tip: I gathered these factoids from journalist David Randall’s Dreamland: Adventures in the Strange Science of Sleep.