How Stress Robs Us of Rest

How Stress Affects Sleep

Sometimes when you have trouble sleeping, and you’re lying in bed staring at the ceiling in the wee hours of the morning, it seems like everyone in the world is slumbering except for you.

But statistics say otherwise. According to a recent survey by the American Academy of Sleep Medicine, 30% of Americans say they have trouble falling asleep or staying asleep. And even before the coronavirus pandemic disrupted our lives, about 20% of people reported insomnia (defined as difficulty falling asleep or staying asleep, or waking up too early) that lasted for up to three months. And 10% of people have chronic insomnia, lasting for three months or more.1,2

Whether it’s the concerns of COVID-19 that keep you up or night (one Stanford University sleep researcher called the pandemic a “perfect storm of sleep problems”)3 or some other distress, loss of sleep is a well-known consequence of stress and anxiety.4 But there’s a bit of a paradox there. Sleep is the ultimate restorative; do we ever feel more relaxed than after a deep, satisfying night’s sleep? 4 If there’s ever time that we need its rejuvenating power, it’s when we’re feeling drained and depleted by stress. And yet so often, that’s when we find ourselves wide awake with worry. Why does sleep seem to abandon just when we need it most?



The answer is connected to the nature of sleep itself; specifically, that it leaves us so vulnerable.

Science tells us that when there’s danger afoot, we have a pretty powerful threat-detection system to keep us safe. When our senses detect something that might be hazardous, our brain triggers all sorts of physiological changes to prep us to fight or flee. Our heart rate and breathing speed up: blood flow increases to our muscles; hormones are released to amp up our strength and stamina. When the danger passes, we return to a relaxed state.5

For most of us, the biggest threat we face in a deep sleep is missing the alarm clock and being late for work (or, these days, late for the 9 am staff zoom meeting). But for our prehistoric ancestors, without the luxury of bedrooms or front doors, sleeping with a threat in the vicinity could be a fatal mistake. So we’ve inherited a fight-or-flight instinct that can keep us awake at night if something’s tripped our danger sense. Better to be sleepy the next day than eaten by a predator, after all.

Our big, complex brains have the ability to respond not only to a threat right in front of us, but to the idea of that threat even after it’s passed. In essence, we create a mental model of that danger in our minds, to better be able to figure it out. What ’s more, we can even construct mental models of a threat that doesn’t exist, and may never come pass. And sometimes that image remains with us, and we keep turning it over in our heads.5 In other words . . . we worry about it. Our worry that we might lose our job, or break up with our partner, or whatever it is that we’re fixated on, is enough of a danger signal to convince our brain that even though we’re lying safe in bed, there’s a threat and we’d better stay awake and vigilant.

“We live in an increasingly 24-7 society, where we are constantly on the go, often right up until bedtime,” explains Wendy Troxel, PhD, adjunct faculty in psychiatry and psychology at the University of Pittsburgh, and scientific advisor to Feelmore Labs. “So we are racing off to bed without giving our brains and bodies an opportunity to unwind. Then we lie in bed and feel frustrated and stressed because we can’t immediately fall off to sleep.”


stress and the relationship to sleep


Research suggests that stress keeps us awake through perseverative cognition: persistent, negative ruminating over things that are going wrong, have gone wrong, or will go wrong.5,6 One study of over 3,000 people found that among people who had very demanding jobs, their sleep quality was worse if they engaged in high levels of preservative cognition about their work. Similar results were found in a study of PhD candidates preparing to present their thesis research: the more they reported preservative cognition about this upcoming stressful event, the more sleep problems they experienced.

Two broad strategies can help when you find yourself tossing and turning night after night. “Practicing healthy sleep habits, and managing stress, are both important strategies to reduce the negative impacts of stress on our sleep,” says Dr. Troxel. Sleep hygiene basically refers practicing all the healthy sleep habits your mom enforced when you were a kid: go to bed on and wake up at the same time every day; keep your bedroom quiet and calm, turn down the lights at night, and so on. “During COVID, many people’s bedtime and wake-up times have become very inconsistent,” Dr. Troxel notes. “Inconsistent routines, including sleep-wake schedules, can lead to poorer quality sleep.” And stress management means doing what it takes to relax, whether it’s meditation, regular exercise (but not close to bedtime), a warm bath, or even a formal therapeutic practice like cognitive behavioral therapy. Adopting a more positive attitude can help, too; one study found that people who tested high for optimism were 74% less likely to report having insomnia.7





[3] ontinues/

[4] Stress, fatigue, and sleep quality leading up to and following a stressful life event. Stress Health 2016; 1–11

[5] When Worries Make You Sick: A Review of Perseverative Cognition, the Default Stress Response and Somatic Health

[6] Perseverative cognition as an explanatory mechanism in the relation between job demands and sleep quality

[7] The Association of Optimism with Sleep Duration and Quality: Findings from the Coronary Artery Risk and Development in Young Adults (CARDIA) Study Behavioral Medicine Volume 46, 2020 – Issue 2