Disrupted routines and worries about coronavirus have made it harder for us to sleep this year. For example, reports suggest there was a 15% increase in prescriptions for sleep medications at the beginning of the pandemic in the U.S., and a 37% increase in insomnia in China.

Importantly, if you’ve been feeling out of sorts over the past few months, lack of sleep could be partly to blame. According to new research conducted before the pandemic, sleep deprivation dampens our enthusiasm about positive events, and makes it harder to find the silver linings when we’re under stress.

In the paper, published earlier this year in Health Psychology, researchers surveyed nearly 2,000 adults in the United States. For eight days, participants received a phone call each evening in which they were asked to report how much they’d slept the night before, whether they had experienced any stressful or positive events, and their overall levels of positive and negative emotions.

When participants got more sleep, they had higher levels of positive emotions and lower levels of negative emotions the next day.

Moreover, sleep impacted how the events of the day affected them.

On days when participants had a stressful event, their positive emotions took less of a hit if they’d had a good night’s sleep beforehand.

And, on days when good things happened, participants experienced an even greater boost in positive emotions if they were well-rested.

These benefits were even more pronounced for people who had a greater number of chronic health conditions, such as allergies, high blood pressure, or diabetes.

Sleep has many wide-ranging effects on our lives.

For example, past research has found that sleep deprivation is a risk factor for developing chronic health issues. And its impact on positive emotions could partly help explain this, since positive emotions seem to reduce our inflammation and protect our health. In other words, sleep’s effect on our moods could even translate to better or worse health over time.

In addition to health, sleep deprivation can also impact our relationships with others—in two ways, says Nancy Sin, assistant professor at the University of British Columbia and lead author of the paper.

First, the irritability you feel when sleep-deprived can harm relationships directly (which might be a reason to postpone serious conversations to a day when you’re more well-rested).

Additionally, because positive emotions play a crucial role in building relationships, not experiencing as many positive emotions when you’re sleep-deprived could make it harder to cultivate a sense of closeness with others.

However, the good news is that simple changes to our routines can help improve sleep. Things like keeping a regular schedule, exercising, and limiting unnecessary light and noise in your bedroom can all help promote sleep.

One major recommendation is to limit screen time before bed; research suggests that electronics can emit blue light that interferes with sleep. If you often find yourself “doomscrolling” on social media during late-night hours, consider setting a time to turn off screens and switch to a more relaxing activity (like reading or listening to calming music).

For those who live with family or roommates, Nancy emphasises that getting a good night’s sleep isn’t solely an individual effort: The behaviours of those we live with can disrupt our sleep. So, for example, consider making a pact with household members to limit screen time, and holding each other accountable.

It’s important to recognise that we’ve experienced huge changes to our routines since March, Nancy says, as many people have faced economic uncertainty, had to adjust to working from home, or cared for children while schools were closed. In that light, it’s probably not too surprising that so many of us have experienced sleep disruptions. Although it wasn’t the case in this new study, other research suggests that stress can make it harder to sleep (particularly if the stressful event occurs close to bedtime).

The flip side is that improving sleep has the potential to help us cope more effectively with the stresses we’re facing right now. As Nancy explains;

“Maintaining good sleep is one of these critical aspects of staying healthy emotionally and psychologically during this time.”