The Importance of Sleep

So many people I know complain about not getting enough sleep, yet it is essential to good health.  If you fall into that category, you’ll be interested in a new book Nodding Off: The Science of Sleep from Cradle to Grave by sleep researcher Alice Gregory of Goldsmiths, University of London.

I discovered this work by reading an interview with the author published in Smithsonian magazine’s VIP newsletter for June 2018.  I’m taking the liberty of reprinting the interview without permission.

Why has sleep become so much less of a priority for modern Americans?

Scientists disagree here, but I’m not entirely sure that it has. It’s true that lots of people get nowhere near the recommended amount (which is seven to nine hours for most young and middle-aged adults). However, when we look at data collected on sleep length over recent decades it is unclear whether it has changed much over this time. One study found that the proportion of short sleepers did increase between 1975 and 2006, but only among those who have full-time jobs.

One reason for this might be that the public attitude toward sleep has not been very positive. Some political leaders brag about being able to function on very little sleep, and we’ve probably all heard sayings such as “sleep is for wimps,” “money never sleeps,” “you snooze, you lose” and “I’ll sleep when I’m dead.” It’s only now that the full importance of sleep is seeping into public awareness.

What are some surprising facts about sleep?

Many people know that dolphins sleep half a brain at a time. Fewer people probably know that night-time erections in armadillos occur at a different stage of sleep than they do in humans! It has been reported that adolescents from many different countries tend toward a later bedtime and an earlier rise time, and this is even found in some non-human mammals. I also think it’s intriguing that age-related changes to our eyes (filtering light in a different way) could be linked to sleep problems in older adults.

What is the biggest misconception about sleep?

While people are only beginning to understand that it’s important not to scrimp on sleep, that doesn’t mean we should increase our sleep length as much as we can. A number of studies have highlighted associations between long sleep and various problems such as cardiovascular disease, obesity and even mortality. As scientists we are not entirely sure why that should be, but there are multiple possibilities. Just as shift workers struggle because they are awake when their bodies are better suited to being asleep, perhaps long sleepers are asleep when they would be better suited to being awake. Maybe excessive sleep is sometimes a sign of a physical or mental disorder. Perhaps long sleep leads to greater sleep fragmentation, which means that we do not get the type of sleep that we need.

What do you think will be the next big revelation in sleep?

Over the past few years, there has been an explosion in products focusing on sleep. There are baby clothes designed to stop our little ones climbing out of cots, pillows that have their very own arm so that the recipient can be cuddled during the night, red lights for the inside of toilet bowls so that we don’t disrupt our melatonin levels, clamps to stop our partners hogging the bedsheets, and so on. I think that some of these have been very well thought out, designed and tested, and are likely to be helpful to many people—or at the very least a bit of fun. However, some products, such as those that monitor sleep, might contribute to sleep problems. Colin Espie from the University of Oxford developed an influential theory that sleep should be automatic and not contrived. He sometimes draws an amusing analogy with golf, noting that when you think about your own performance too much it can all go dramatically wrong. We might want to keep that in mind moving forward.

What are your best and worst sleep habits?

One of my best sleep habits is that I am pretty boring when it comes to my routine. I go to sleep at the same time most nights (around 10 p.m.). My young children act as an alarm clock in the morning, which means that my wake-up time is pretty consistent, too, even on the weekend. I am also acutely aware of the factors that might aid or disrupt my sleep. I typically avoid working at night, so I am not exposed to mental arousal or the light emitted from my computer. I try to get some sunlight in the day and dim the lights at night, so my body can keep track of what time of day it is. However, I occasionally drink coffee in the afternoon and I rarely turn down a glass of wine just because it might disturb my sleep quality. But if it comes to prioritizing sleep by getting an early night and leaving the dishes until the morning, count me in!

Katherine J. Wu

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