Do people try to give you advice about how to fix your sleep problems? Does all their advice seem completely and utterly useless?

The problem with sleep advice is that it is rarely if ever specific to the person who needs it. And sleep, it turns out, is deeply personal, probably even more personal that most of us would assume.

The more scientists study sleep, the more issues related to sleep—how long we sleep, what time we go to bed, when we wake up, and how we cope when we’re sleep deprived—seem in part to be deeply coded into our DNA.

For example, in writing about sleep deprivation and how well people cope with it, one researcher describes each person’s response as being like a “trait” (Killgore 2010). How well any one person reacts to not getting enough sleep is not a skill, nor is it learned behavior. It’s not something we can practice and improve. Saying it’s like a trait is to imply that there’s something inherent in each person, something we are born being, that defines our responses and reactions to how and when and for how long we sleep. Those things are shaped only a little bit through learned behavior.

What is a Chronotype?

I’m currently reading a book by one of the most important researchers on chronotypes, Till Roenneberg, called Internal Time: Chronotypes, Social Jet Lag, and Why You’re So Tired.

“Chronotype” essentially means one’s internal clock. The whole business of someone being an “early bird” or a “night owl” is real, and it’s also not learned behavior. Being an early bird, or lark as it’s more often called now, or an owl isn’t the only differentiation between people either. Some people are long sleepers, requiring maybe 10 hours of sleep a night to feel recuperated, and some are short sleepers. Most people, on average, need somewhere around 7.5 to 8 hours of sleep. But that’s an average and there are exceptions. A very small portion of people can survive just fine on 5 or 6 or six hours of sleep, but they’re rare. The long sleepers are equally rare. But if you are one and you have problems with sleep, you certainly need to know it before you take any advice seriously. Otherwise, that advice may not be for you.

Why Sleep Advice Rarely Works

Now consider someone who needs 10 hours of sleep but also has an internal drive to stay up later than most. Having a preternatural drive to go to bed no earlier than midnight and a need to sleep until 10 a.m. makes it difficult to get to a typical office job by 8:30 every morning. The advice “go to be earlier” won’t necessarily work. If someone is not coded to feel tired at 10 p.m., climbing into bed at that time isn’t suddenly going to change it.

When writers and experts share science-based advice about anything, they’re usually looking first at research that describes what happens on average. It’s true that on average, most people need somewhere in the realm of 7.5 to 8 hours of sleep. Most people working in Western office culture also have to get up and be at work by somewhere between 8 a.m. and 9:30 a.m. So given those norms, they’ll recommend a specific window of time when to go to bed, based on getting 8 hours of sleep, as well as a routine to follow before hitting the hay. All that advice comes from research that proves what works on average.

Averages aren’t always useful. In a recent episode of the podcast 99 Percent Invisible, Roman Mars and his team describe the history of “averages,” which was for a long time nothing more than a mathematical concept used mainly by astronomers. It was eventually applied to solider’s uniforms, at a time in history when making a fitted uniform for every single solider started to seem ridiculous. Then it was applied to the design of cockpits (this is before adjustable seats). In finding the average size of a pilot’s height, arms, legs, shoulder width, and so forth, designers thought they’d make an ideal space for flying planes. But of course, the design of the plane itself now excluded certain people from becoming pilots at all. More importantly, the final cockpit didn’t fit anyone ideally. It might fit one person’s leg length, but not his arms. Or it might fit his arms, but the seat was too low. In trying to design a cockpit based on averages, planes ended up with seats that fit almost no one.

So think about that concept now as it relates to sleep and sleep advice. If we all have unique sleep needs, how can any advice that’s based on averages do us any good?

As I’ve already suggested, figuring out an ideal number of hours to sleep is only the beginning. Determining when to sleep is just as important. The answer is not the same for everyone. Other factors, including age and sex, affect how each person needs to sleep, too.

What Can You Do?

Sleep is amazingly important to personal productivity. When we don’t sleep enough (“enough” is a unique number for each person) we are more likely to lose focus, have poor judgement, and even see our creativity suffer. Again, how well we cope with lack of sleep is also unique.

So rather than take concrete advice about sleep, a better course of action is to reap what we can from science to understand what’s possible and likely, and then apply it as we see fit to our own situation.

References

Killgore, W. D. S. (2010). Effects of sleep deprivation on cognition. Progress in Brain Research, Elsevier. DOI: 10.1016/B978-0-444-53702-7.00007-5. Retrieved 29 July 2016.

Roenneberg, T. (2012). Internal Time: Chronotypes, Social Jet Lag, and Why You’re So Tired. Harvard University Press.

Image by John Huss, CC.