And, bigger picture, about 10 percent of us admit our sleep deprivation makes it difficult to concentrate and that we just can't keep up when it comes to our overall productivity [source: National Sleep Foundation].
It's easy to blame our inability to fall asleep – or stay asleep – on the stress and demands of a modern lifestyle, but it turns out that insomnia is not a modern-day phenomenon (although our always-on lifestyles aren't helping).
Insomnia isn't what happens when you nap too long in the afternoon and can't manage to get to sleep at your normal bedtime that night; that's just poor planning. The brains of insomniacs, it turns out, are more excitable than brains of those with normal sleep patterns. And humans have been suffering with the condition since at least the times of ancient Egypt (and, likely, deeper into human history than that). Opium cures for insomniacs are described in ancient Egyptian documents, and insomnia itself is referred to as "to be in bed and sleep not," one of the "three living hells" described on an Egyptian hieroglyph [sources: Parker-Pope, Todman]. While we don't know how prevalent sleep disorders were among the ancients, we do know how pervasive the problem is today. Almost half of Americans suffer from occasional insomnia; about one-third suffer enough from sleep deprivation to gripe about how tired they are; and almost a quarter suffer from more chronic, frequent insomnia symptoms [sources: National Sleep Foundation, Parker-Pope].
Perhaps not all of us are using our sleep habits to our advantage: About 41 percent of us consider ourselves more productive at night, yet only about 3 percent of the American workforce is made up of night owls [sources: Zupek, Bierma]. Creatures of the night, we can do better. Consider how much better the smell of bread dough rising in the moonlight is compared to another sleepless night staring at the moon from your bed.