If you've been having trouble falling asleep or staying asleep through the night, you may want to try listening to pink noise. What is pink noise exactly? As the Sleep Foundation explains, "Pink noise is a sound that contains a random assortment of all the audible frequencies, with more power in the lower frequencies. Specifically, pink noise contains the same overall intensity in each octave, but the volume of individual pitches decreases by 3 decibels with each higher octave." In other words, it's like a pleasant, balanced hum.
Pink noise is common in nature sounds like "rain, waterfall, wind, river, [and] ocean waves," says the article. It's also been observed in snippets of birdsong and urban noise. Researchers often use pink noise as a control sound in studies because it's less distracting than other types of noise.
So how can pink noise help you sleep better? Studies show it may help you fall asleep faster, sleep more deeply, and wake up feeling more refreshed.
According to the Sleep Foundation, steady pink noise played at a reasonable volume "helps people relax for sleep by masking bothersome sounds." One study found that playing steady pink noise at 60 decibels helped participants fall asleep faster. Another study used a system that decreased the volume of a pink noise track as the person fell asleep, which "helped them reach deep sleep earlier."
Multiple studies have also found that pink noise enhances the quality of sleep. It can synchronize with brain waves to stabilize sleep, and timed quiet bursts of pink noise during the night may improve deep sleep. As the article explains, "Deep sleep is the most restorative sleep stage and it plays a prominent role in immune system functioning." Enhancing deep sleep with pink noise may provide benefits for stress hormones and cardiovascular health.
If you're looking to try out pink noise yourself, the Sleep Foundation recommends playing it at 60 decibels, about the volume of a refrigerator. You can find pink noise tracks on YouTube, sleep apps, and sound machines. Just be sure to keep the volume at a safe level. Set a timer if you don't want the noise to play all night.
Previously: The Colors of Noise: different kinds of static have distinctive tones