It’s 1 a.m. and you’re doomscrolling through Twitter, dreading another day of getting your kids through virtual school, and worrying about your ill mother. You finally begin to nod off, until suddenly, passing sirens sound off outside of your window, jolting you awake.

Getting a good night’s rest can be difficult even under the best of circumstances. According to a 2018 study from Penn Medicine researchers, about a quarter of Americans experience acute insomnia each year.

But the increased stress and anxiety of the COVID-19 pandemic is exacerbating sleep issues — leading to what some experts have dubbed “COVID-somnia” or “coronasomnia.”

That’s why many people rely on the low, static buzz of a sleep sound machine or smartphone application when they can’t sleep. A quick search for “white noise sleep” brings up 87,100 Google News results, and more than 200 white noise applications are available for download on Google Play.

White noise is not only purported to mask disruptive noises, but also to be a non-pharmacological approach for promoting sleep and improving its quality.

Is white noise good for sleeping?

Mathias Basner, MD, PhD, a professor of Sleep and Chronobiology in Psychiatry at the University of Pennsylvania’s Perelman School of Medicine, is skeptical.

“We’re trying to fight noise with noise, which is a weird concept,” said Basner, who studies the effects of noise on sleep and health.

After reviewing the existing scientific literature, Basner and a team of researchers found only 38 clinical studies that tested the effects of white noise on sleep. And from their analysis of these studies, they saw no clear evidence to support the assertion that noise will help you sleep better.

“Overall, I’m concerned that so many people are using these machines, but there is very little evidence supporting that they work, and there could be detrimental effects that we don’t yet know about,” Basner said.

How white noise may help you sleep

There are three main theories for how white noise machines may improve sleep, according to Samantha Riedy, PhD, a postdoctoral researcher in the Division of Sleep and Chronobiology and the review paper’s first author:

• The dull, repetitive sound may have some sleep-promoting or calming properties that lulls the brain into sleep. There is some limited evidence, for example, that the sound of rain or ocean waves crashing facilitates sleep in children, by decreasing heart and respiratory rate.
• The second theory is that the white noise has a Pavlovian effect and works as a sleep cue — helping to “train your brain” that it’s bedtime whenever the machine turns on.
• The third idea, Riedy says, is that the white noise machine “masks” other external sounds by “raising your arousal threshold.” That’s a fancy way of saying that the white noise might drown out your neighbor partying in an adjacent apartment unit. However, the Penn researchers found that the quality of the existing studies was so low, that there is almost no research to support a single one of these theories. The pitfalls in past studies included: very small sample sizes (some as small as a single participant), a lack of consistency in the types of tools used to measure noise levels and sleep quality, and poor descriptions of the noise being studied.

Why it may be better to sleep in silence

While some might point to their own anecdotal experiences as evidence that noise machines do in fact promote sleep, the researchers caution against this assumption.

“It might be useful in getting someone to fall asleep more quickly, but of course, trying to subjectively self-assess your own sleep is problematic, because you’re unconscious,” said the paper’s co-author Michael Smith, PhD, a postdoctoral researcher in the Division of Sleep and Chronobiology.

Getting quality sleep is critical for a person’s overall health and well-being, Smith said. And if a noise machine is fragmenting your sleep without your knowledge, “it could be making your sleep less restorative.”

Moreover, it’s possible that the white noise might be actually harming your hearing.

“We don’t know this for sure, but it’s possible that the auditory system needs the quiet time during sleep to rest, essentially. By introducing noise during this downtime period, you’re potentially stimulating the system, which may preclude it from rest and recovery,” Smith said.

That is why Basner also would not recommend that people use music or podcasts to fall asleep, unless they have a timer set for the sound to shut off.

“We first need to verify in controlled laboratory studies whether white noise promotes sleep in noisy environments, and if everybody reacts in the same way. We then need to move to more realistic long-term studies in the home environment.,” Basner said.

Sleeping with COVID-19: How to get some rest

In the meantime, Basner said that good old-fashioned sleep hygiene practices are the best way to ensure a good night’s rest: having a bedtime routine, avoiding screens and bright light before sleep, no caffeine or alcohol in the evening, sleeping in a cool, quiet environment.

For those with anxiety that prevents them from falling asleep, cognitive behavioral therapy for insomnia is a proven solution.

But if you live on a noisy street or have a partner who snores? You might be out of luck.

“You can get ear plugs,” Smith said. “But that’s a bit like putting a gas mask on during a fire.”