The Sleeper’s Dilemma
New research shows how skipping sleep can hurt your health.
Posted Feb 16, 2018
This guest post was contributed by Shubir Dutt, a graduate student in USC's Clinical Psychology program.
It’s 11:30 p.m., and you just completed a work assignment, put the kids to bed, or finished up your chores — whatever signals the end of a long day for you. You feel a little fatigued, but the next episode of your favorite show is just begging to be watched now that you have some free time. “What’s one less hour of sleep, really?” you say, as you put on your headphones. But the consequences of prioritizing your favorite show over a good night’s rest are more than just a headache the following morning: This one little decision may lead to your physical and mental health suffering in the long term.
Most people are familiar with the typical costs of a disrupted night of sleep — grogginess, fatigue, and a generally unpleasant feeling the next day. However, these bothersome hangover-like symptoms are only the immediately obvious consequences of insufficient sleep. We may, in addition, be harming key thinking abilities, as well as the way our brain develops and communicates. And we may even be increasing our risk of heart disease or Alzheimer’s disease. How can sleep, something unconscious that most of us take for granted, facilitate the development of deadly diseases and impaired thinking? Sleep researchers may have the answer.
A recent review article by graduate student Adam Krause and colleagues at the University of California, Berkeley, detailed how our brain and cognitive abilities can suffer when we don’t get enough sleep. Sleep deprivation can lead to lapses in attention, harming our ability to orient ourselves to relevant information in our environment. Sleep loss can also affect our working memory, which lets us keep recently learned information (like a phone number or address) immediately available in the front of our minds. Sleep deprivation additionally disrupts key brain networks and the regulation of the neurotransmitter dopamine, leading to riskier decision-making and increased experience of negative emotions — no wonder people call you cranky when you don’t get enough sleep! That late-night Netflix binge doesn’t sound quite as tempting now, does it?
It’s starting to become more apparent that sleep is vital to our day-to-day functioning, but what about the long-term effects of poor sleeping habits? Researchers have theorized that getting insufficient sleep can lead to increased levels of beta-amyloid, a molecule closely tied to Alzheimer’s disease. Think of the beta-amyloids as the gunk that builds up on the sidewalk of your brain as you age, needing to be regularly cleaned and washed away. A study done at the University of Rochester found that sleep can function as a street sweeper, helping to clear out many toxins overnight (including beta-amyloid) from the brains of mice. Researchers at Washington University in St. Louis extended this work to humans and found that a lack of sleep, and thus a lack of our brain’s street sweeper, led to increased levels of beta-amyloid. Though we still don’t know whether a lack of sleep directly causes more gunk to build up, or if the gunk buildup causes our disrupted sleep, some research groups, such as the previously mentioned one at UC Berkeley, are attempting to shed more light on this mystery. A recent study of theirs found in older adults that spending less time in a specific stage of sleep known as “deep sleep” was associated with higher levels of that pesky beta-amyloid and worse memory. What’s the point of watching that late-night TV episode if you aren’t able to remember it?
Getting high-quality sleep is not only important for your brain and mental functioning, but can also help fight chronic illnesses. A 2011 meta-analysis of published research studies, conducted by scientists at the University of Warwick, found that shorter sleep (<7 hours) was linked to an increased risk of developing coronary heart disease and stroke. Interestingly, the same study also found that abnormally long sleep (>9 hours) was also linked to the development of cardiovascular disease. The exact mechanism explaining how this is happening is still not clear, but these findings do suggest that there may be an optimal Goldilocks amount of sleep (7 to 9 hours) that we should aim to get — not too little and not too much, but just the right amount. Other studies, such as those discussed in a review article by Dr. Michael Irwin at UCLA, have similarly linked poor sleep to the development of depression and even cancer, suggesting that we all could benefit from paying more attention to our sleep habits. Your favorite show can probably wait until tomorrow if it means protecting you against chronic diseases!
While a lot of this research can seem scary and disheartening, there are active steps you can take to change your sleep habits — starting tonight! Twenty or thirty years ago, people would have laughed if you told them you could monitor your sleep at home without a bunch of annoying and expensive equipment — but now you can. Devices like Fitbit monitors and Apple watches can track your total sleep time, as well as your time spent in different sleep stages. But you don’t have to spend money to start making changes! Many people are noticing their poor sleeping habits and actively trying to improve their “sleep hygiene” in other ways. The National Sleep Foundation suggests several tips for improving “sleep hygiene,” such as avoiding high-fat foods and caffeinated drinks close to bedtime, establishing a consistent bedtime routine, and getting regular exercise. You don’t have to be a rocket scientist (or a brain scientist) to start making simple lifestyle changes that promote good sleep and good health.
But what if you’ve made these lifestyle adjustments and still have trouble sleeping? There are well-validated and widely used talk therapy options for sleep problems. Two of the most popular therapies are CBT-I (Cognitive Behavioral Therapy for Insomnia) and BBTI (Brief Behavioral Therapy for Insomnia); in these treatments, you might do things like keep a sleep diary and review it with a therapist to find specific habits or actions that keep you from getting a good night’s sleep. You probably didn’t think an article about sleep would end up discussing psychotherapy, but talk therapy can be one of the most powerful and effective tools in reclaiming your desired sleep schedule.
Now, after learning a little more about sleep, does that extra late-night hour of TV still make sense? Is it worth it to stay up binge-watching a few episodes, or would you rather prioritize your “sleep hygiene” and get ready for bed instead? It is never easy to change habits overnight, but when it comes to an issue as critical to your health as sleep, an overnight change might be exactly what you need.
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