Meet Pink Noise, The Sleep Aid That Might Be More Effective Than White Noise

Many people who have struggled with falling asleep and staying asleep swear by white noise: “a constant ambient sound,” as described by the National Sleep Foundation, that masks disruptive “peak” sounds like slamming doors, heavy footsteps, and irregular traffic noise. Common sources of white noise are things like humming fans, air conditioners, and humidifiers, or even white noise machines that create an even static sound that can aid insomniacs.

However, a different type of noise has begun to make waves—literally—within the struggling-to-sleep community. It’s called “pink noise,” and it may be more effective than the static white noise sound you currently use to drift off to dreamland.

Both pink and white noise are members of an entire color family of sound including black and brown noise. Sounds are assigned these colors based on how energy is distributed over several frequencies, according to Healthline.com. White noise, for example, is comprised of energy that is equally distributed across all audible frequencies. Brown noise, sometimes called red noise, consists of higher energies at lower frequencies—think thunder and deep, roaring sounds.

Pink noise, on the other hand, is a shade deeper than white noise. It’s similar to white noise in that it includes all audible frequencies; however, unlike white noise, energy is not distributed equally among them. 

“The energy of pink noise is greater at lower frequencies and decreases as the frequency rises. This gives it a distinct sound that is deeper than white noise,” Rose MacDowell, Chief Research Officer at Sleepopolis.com, explains to us. Pink noise contains a mix of high and low frequencies that come in waves like wind, rain, and literal ocean waves.

So, all of you people who like to listen to ocean sounds at bedtime are actually putting pink noise to work.

“Many sleepers believe that white noise does the best job of masking any form of noise pollution, whether is it the garbage truck lumbering up your sleep at 6 am or the neighbor’s dog howling at the moon at midnight,” Bill Fish, Certified Sleep Science Coach and co-founder of Tuck.com, tells Apartment Therapy. “The fact that white noise is evenly distributed across the frequencies assists it in blocking out sounds that may disrupt our sleep.”

“That said,” Fish continues, “studies have shown that these lower frequency sounds known as pink noise can sooth the brain by actually reducing brain waves, which helps for a more sound sleep.”

According to experts who published a 2012 study on pink noise in the Journal of Theoretical Biology, pink noise reduces “brain wave complexity” and can induce “more stable sleep time,” which can therefore improve sleep quality. 

They came to this conclusion after recording the electroencephalogram (EEG) signals, those being electrical activity signals in the brain, of six test subjects who were subjected to 10 minutes of quiet and then 10 minutes of noise. When pink noise was introduced to the experiment, the complexity of the EEG signals decreased and actually synchronized with the pink noise, thus lowering brain wave activity. A related sleep-quality experiment then showed that participants who were exposed to pink noise “showed significant enhancement in the percentage of stable sleep time compared to the control group.”

“Because emotions and experiences are processed during deep sleep, pink noise may also boost memory,” MacDowell adds. “Research suggests that pink noise could help concentration during waking hours, as well.”

MacDowell is referring to the 2017 study in which Phyllis Zee, a neurologist at Northwestern University, used pink noise to enhance deep sleep in older adults in an attempt to improve their memory, the hope here being that pink noise may hold a key to unlocking new treatments to prevent diseases like Alzheimer’s and Parkinson’s. Via their pink noise experiments, Zee and colleagues were able to stimulate the brain’s delta oscillations, which characterize deep sleep, and this resulted in a 25–30% improvement in participants’ recall of word pairs they learned the night before in comparison with a placebo treatment.

However, it must be noted that research around pink noise is still minimal. And, as Fish tells us, “it is highly recommended to try both [white and pink noise] and see what is best for your personal make up.”

To introduce pink noise to your bedtime routine, there are several apps currently on the market that could be life-changing. For those who use Google Play, this “Brown Noise, Pink Noise, and White Noise” app has a 4.8-star rating based on 934 reviews. And this “White & Pink Noise” app on Apple’s App Store has a 4.4-star rating with 348 reviews. Any nature-sound apps should also work pink-noise wonders. You can also purchase a pink noise machine, similar to the more common white noise machines.

And FYI, MacDowell recommends that “pink noise from apps or machines should be kept at a moderate level that won’t damage hearing.” Noted.

So, if white noise hasn’t really been doing you any favors, or if you’re looking to try something different (and perhaps more effective), give the pink noise phenomenon a try. You may just end up having the best sleep of your life.