White, brown and pink noise machines are going viral for improving sleep. Do they work?
Adding noise to your sleep routine may sound counterintuitive, but many people swear by wrapping themselves in a blanket of sound to get a better night of rest.
You’ve probably heard of white noise. Now, other colors of noise like pink and brown are increasingly popular, especially on TikTok. The continuous, ambient sounds are often used to drown out the cacophony of other noises that can keep people up at night.
Many TikTok users hail white, pink and brown noise for its supposed benefits — from improving sleep to promoting relaxation and boosting productivity. There are a growing number of sound machines and apps designed to play these sounds.
What is the difference between white, pink and brown noise and do these actually help improve sleep like people claim?
What is the color of noise?
"The term 'color' of noise is used to describe the strength and frequency of a noise signal on the power spectrum," Shelby Harris, Psy.D., a clinical psychologist specializing in behavioral sleep medicine and director of sleep health at Sleepopolis, tells TODAY.com.
"Different colors of noise have different strengths and frequencies, and as a result, they sound different to the human ear," Harris explains. White, pink and brown noise are all types of noise with varying amounts of energy at different frequencies.
White noise
"White noise contains all frequencies in equal amounts, resulting in a constant hiss or rush similar to the static on a radio (or television)," Harris. It may sound like the continuous hum of a fan, a hair dryer or a vacuum.
It's called white noise because it is analogous to white light, which is a mixture of all the different wavelengths of light together.
White noise is often used to mask other sounds in the environment, says Harris, and many people claim the constant static helps lull their brain to sleep. It's also used to soothe babies because it is said to mimic the sound of amniotic fluid in the womb, TODAY.com previously reported.
Brown noise
Brown noise, also called red noise, is more intense at lower frequencies, which produces a deep, rumbling sound, says Harris — think more bass and less static than white noise.
It may sound like heavy rainfall or wind, waves crashing on the shore, or the low roar of an airplane engine. Brown noise tends to have more natural variation than the other types.
Similar to white noise, brown noise can drown out background noises. Some find that it helps them fall into a deeper, more restorative sleep, NBC New senior medical correspondent Dr. John Torres told TODAY in a segment aired Nov. 15.
Brown noise is especially trendy on TikTok, where users also swear by it to lower stress, ease anxiety and improve focus.
Pink noise
Pink noise is a mix of white noise and brown noise. "It has a decreasing high frequency and sounds like gentle rain or a waterfall," says Harris.
It has a lower pitch than white noise, but it does not have the deep roaring sound of brown noise. Pink noise is often described as softer, quieter and more flat, experts note.
Just like the other colors, pink noise can also filter out disruptive sounds in the background, the experts note. Many claim it has a calming effect and, according to Torres, pink noise can also be used to help people fall and stay asleep.
Do white, pink or brown noise help with sleep?
"Colored noise, particularly white noise, can be beneficial for sleep due to its ability to mask disruptive sounds and promote a feeling of calm and relaxation," says Harris. However, these noises aren't for everyone.
While they help some people doze off, they may do the opposite for others. "Certain sounds can have natural variations or irregular noises that have the potential to wake you up or disturb your sleep quality," Harris adds.
Research on the impact of these noises on sleep is mixed. White noise has been studied the most — but a recent analysis suggests that the science behind the benefits of white noise for sleep is thin, TODAY.com previously reported.
In a 2021 review of 38 studies on the relationship between white noise and sleep, researchers concluded that the quality of the evidence to support white noise as a sleep aid was poor and more research is needed.
Still, some people may find that white, pink or brown noise helps them fall or stay asleep, the experts note — and it probably won't hurt to try it out.
“It’s important to keep sleep sounds at lower volume, as sounds that are too loud can also make it more difficult for you to fall asleep,” says Harris.
It's generally safe to listen to these noises for a prolonged period of time, as long as the volume doesn't reach levels that can harm the ears — anything over 70 decibels, according to the U.S. Centers for Disease Control and Prevention. (For context, the hum of a dishwasher is 60 decibels, per the CDC).
Which color of noise is best?
The color of noise that's best for sleep depends on the individual and their preferences, the experts note.
“White noise is a great option because it has a consistent sound that can help to mask outside noise,” says Harris.
Pink noise may be a good choice if white noise is too high-pitched or irritating, the experts note, and brown noise may be more suitable for those who want a deeper sound.
“Some noises can irritate people, especially children, so be careful,” says Torres. The experts encourage people to experiment with different colors of noise to see which one they like best.
"There are different sleep machines, alarm clocks, and apps that people can use for sleep sounds and noise, and you can pick the one that you find most relaxing for better sleep," Harris says.
White, pink or brown noise can also be used with other relaxation techniques, such as deep breathing or meditation, Harris adds.
Tips to get a better night's sleep
One-third of U.S. adults report that they usually get less than the recommended seven to nine hours of sleep, per the CDC. The experts recommend the following tips to get a better night's rest:
Establish a regular sleep schedule
Create a relaxing wind-down routine before bedtime
Optimizing your sleep environment by ensuring it’s dark, quiet, and cool
Avoid screens for 30 minutes to an hour before bedtime
Expose yourself to sunlight in the morning when you wake up
Limit caffeine, alcohol and tobacco
"If these suggestions aren’t enough, talk with your doctor," says Harris.
This article was originally published on TODAY.com