Is sleeping with background noise bad?

There's no clear yes or no, and the newest research leans toward caution. Two systematic reviews found the evidence that continuous noise improves sleep weak, and a 2026 lab study found that pink noise reduced REM sleep in healthy adults. The 2026 authors call for research on long-term use, so these studies can't tell you what years of nightly noise do.

What the studies found

The 2021 review. Riedy and colleagues at the University of Pennsylvania reviewed 38 studies of continuous white noise or similar broadband noise and sleep (Sleep Medicine Reviews). The studies varied in the noise used, how sleep was measured, how closely people stuck to it and what they were compared with. The authors say that may be why results ran from continuous noise improving sleep to continuous noise disrupting it. Using the GRADE criteria, they rated the quality of evidence that continuous noise improves sleep as "very low", which they note "contradicts its widespread use". They also wrote that continuous noise may negatively affect sleep and hearing, and asked for studies with objective sleep measures before it's promoted as a sleep aid.

The 2022 review. Capezuti and colleagues, in the Journal of Clinical Sleep Medicine, covered 34 studies with 1,103 people in total, testing white noise, pink noise and mixes of sounds. Nineteen of the 34 had positive findings on sleep outcomes. The authors still concluded there was "no strong evidence to support use of auditory stimulation", and none of the studies reported adverse effects with short-term use.

The 2026 lab study. Basner and colleagues ran a seven-night polysomnography study in 25 healthy adults (average age 28.5). Nights included intermittent environmental noise (93 noise events), pink noise at 40 or 50 dBA, earplugs, and combinations, and each was compared with a noise-free control night. Pink noise reduced REM sleep compared with the control night, and adding pink noise to environmental noise worsened sleep structure, despite small improvements in the sleep fragmentation the environmental noise caused. Earplugs reduced nearly all of the effects of environmental noise, though they started to fail at the loudest level tested (65 dBA). Next-morning cognitive tests, cardiovascular measurements and hearing tests were not affected, but people rated their sleep, alertness and mood worse after the noise nights. The authors wrote that the REM findings "caution against the widespread and indiscriminate use of broadband noise" and called for research on the best noise type and level, and on long-term use.

What the evidence can't tell you

The 2026 study was small, short and made up of healthy young adults, and the only masking sound it tested was pink noise. A result about pink noise in a lab doesn't automatically carry over to every steady sound in every bedroom.

What this means if you like a steady sound

The research gives you reasons to try it carefully rather than a verdict. These steps are practical, not findings from the studies:

1. Keep the volume low. The 2021 review raised hearing as a concern, so the quietest level that works for you is a sensible start.
2. Use a timer so the sound doesn't have to run all night.
3. Compare a few nights with and without it. If you sleep worse with the noise, drop it.
4. If a noisy bedroom is the problem, note that in the 2026 study earplugs blocked nearly all the effects of environmental noise, while pink noise did not.
5. If sleep is a problem most nights, talk to a clinician. A sound isn't a treatment.

For more on fans specifically, see sleeping with a fan on, fan noise for sleeping and is a fan white noise.

Trying it with Fan Noise

Fan Noise plays recordings of fans on iPhone. It doesn't track sleep and makes no health claims, so it works as a way to run the test above.

1. Pick a sound. On the Sounds tab, tap "Change sound". Classic Ceiling Fan, Modern Tower Fan and Window Box Fan are free. Industrial Fan and Quiet Breeze are Premium.
2. Set the volume with the slider, then press play.
3. Choose a fade-out and start the "Sleep timer". The "Fade-out" menu offers 30s, 1m, 2m and 5m. Tapping 15m, 30m, 1h or 2h starts the timer with that fade-out, so the sound tapers off and stops.
4. Lock your phone. The sound keeps playing with the screen locked, with play and pause on the Lock Screen.

It works offline because the sounds are stored in the app, and there are no ads and no account.

This guide summarizes published research for general information. It isn't medical advice and doesn't diagnose or treat any sleep condition.