Getting through the workday on little sleep is a point of pride for some. But skimping on shuteye could be shortening your life and making you a less than stellar employee, according to Matthew Walker, founder and director of the Center for Human Sleep Science at the University of California, Berkeley.
“Underslept employees tend to create fewer novel solutions to problems, they’re less productive in their work and they take on easier challenges at work,” said Walker, author of “Why We Sleep: Unlocking the Power of Sleep and Dreams,” out Tuesday.
Operating on short sleep — anything less than seven hours — impairs a host of brain and bodily functions, said Walker, who is also a professor of neuroscience and psychology. It increases your risk for heart attack, cancer and stroke, compromises your immune system and makes you emotionally irrational, less charismatic and more prone to lying.
We spoke to the sleep scientist about what’s keeping us from getting to bed and how we can make the most of our slumber.
Q: What do you say to people who sacrifice sleep to work?
I often ask the question in return, “Is the reason you’ve still got so much to do because you haven’t gotten enough sleep and so you’re inefficient while you’re working?” We know that efficiency and effectiveness are increased when you’re getting sufficient sleep and it will take you longer to do the same thing on an underslept brain, which means you end up having to stay awake longer. So goes the vicious cycle.
Q: How much sleep should we be getting?
The recommendation is seven to nine hours for all adults. The reason that there’s a range is that it’s a little bit like calories. Based on everyone’s unique physiology, that amount will vary from one person to the next.
And the same is true for sleep, although there are somewhat hard boundaries on the lower end. Once you get less than seven hours of sleep, you can measure marked impairments in both brain and body health. And those people who claim they can survive on six hours of sleep or less, unfortunately, are deluding themselves and their health.
Q: How does someone know if they’re getting enough sleep?
If you were not to set an alarm clock, would you sleep past it? If the answer is yes, then there is clearly more sleep that is needed.
Do you tend to sleep in during the weekends? That usually signals that you’re trying to sleep off a debt you’ve accumulated during the week. By the way, it doesn’t work like that. It doesn’t work like the bank. You can’t accumulate a debt and then pay it off at a later point in time.
And if you feel like you need caffeine in the morning, then you’re probably self-medicating your state of sleep deprivation.
Q: What happens when you drink caffeine late in the day?
The gross demonstration of caffeine is that it prevents you from falling asleep. The slightly more nefarious aspect of caffeine is that maybe you can fall asleep, but we know that the depth of deep sleep you’re getting if caffeine is still in your system is severely less. So those people who say, “I can fall asleep just fine,” it still doesn’t mean they’re safe and clear from the reaching arm of caffeine into their sleep.
Q: How about that post-work cocktail or nightly wine habit?
There is a misunderstanding that alcohol helps you fall asleep. Alcohol is a sedative. Sedation is not sleep — it doesn’t come with the same restorative benefits. If you consume alcohol six to eight hours before bed, the first thing that alcohol is very good at doing is blocking your REM sleep, your dream sleep. Dream sleep has a whole collection of functions for the brain and the body.
It also fragments your sleep. You will wake up many more times a night than if you weren’t drinking. Those awakenings tend to be quite brief and many people don’t commit them to memory. So they wake up the next morning and feel unrefreshed and not particularly chipper. And they never connect the dots, which is perhaps it was the glass of red wine I had before bed and it was the multiple awakenings that I had throughout the night that makes me feel this sluggish and underslept the next day.
Q: So how do we get our body ready for sleep?
An hour before bed, you really should stop using screens. We are a dark-deprived society and LED screens, even light inside of a room, can block your rising levels of melatonin and sort of push the onset of sleep later in time. So if you start to create dim lights and dim the screens, those things will help. If you have to work, use the software that desaturates the light. But really, you should probably stop.
Q: What do you use to help you sleep?
I’ve got some earplugs and I’ve got a face mask. When I travel, I definitely do that. When I’m at home, I have blackout curtains. So, hokey as it sounds, I do practice what I preach.
Q-and-A’s are edited for length and clarity.