White, pink or brown noise: which helps you sleep?

White noise has made its way into sleep apps, smart speakers, and baby nurseries. The question I get on my phone is almost always the same: does it really help? It helps some people, for a simple mechanical reason. And the volume you set it to matters more than the color you choose.

Before you go on, if you haven't covered the basics yet, here's the starting point: Sleep hygiene: 12 habits for better sleep.

The three colors of noise, in simple terms

  • White noise — equal energy across all audible frequencies. Sounds like TV static or a hairdryer.
  • Pink noise — energy decreases as frequency increases. Sounds like steady rain or wind in the trees. This is what most people describe as softer.
  • Brown noise — the drop is even more pronounced. Almost only the bass remains: waterfall, distant thunder.

The function is the same for all three: masking. A continuous sound reduces the contrast between the silence of the room and a car braking in the street. What wakes you up is rarely the noise itself — it's the sudden change in noise.

What the evidence shows (and what it doesn't)

Reviews published in recent years almost all come to the same conclusion: studies are small, short, and use different methods. There are signs that continuous sound shortens the time it takes to fall asleep in noisy environments. There is no solid proof that it improves sleep structure in those who already sleep in a quiet room.

In practice: if you live on an avenue, it makes sense to try it. If your room is quiet and you still wake up at four in the morning, sound is not the variable you're missing.

Noise masks the symptom, not the cause

I see many people using sound to compensate for something else. A snoring partner. A mattress that no longer provides support. Screens late at night. If the noise that wakes you up comes from the bed next to you, the solution is different: snoring — why it happens and how to reduce it. If you wake up with pain and your mattress is over ten years old, that's the most likely hypothesis — and the guide on how to choose the ideal mattress will answer your questions in twenty minutes of reading.

Volume: the part almost everyone ignores

The World Health Organization recommends keeping night noise in the bedroom below 40 dB. A poorly placed sound machine can easily exceed this. Three rules I usually give:

  • Volume sufficient to soften outside noise, not to block it out. If you have to raise your voice to speak over it, it's too loud.
  • Move the source away from the headboard. Never on the nightstand, next to your ear.
  • Timer for 30 to 60 minutes. The useful part is the transition to sleep; all night rarely adds anything.

In the baby's room, the rules are different

A study that tested fourteen baby noise machines measured, at the shortest distance, levels above 85 dB — above the occupational exposure limit for adults. Practical rules: more than two meters away from the crib, low volume, and turn it off after the child falls asleep. Never inside the crib. The rest of the context is in the baby sleep guide for parents.

This article is for informational purposes only and does not replace medical evaluation. If you stop breathing during the night (or have been told you do), if you have tinnitus, or if insomnia has lasted for more than three months, talk to your doctor before adopting any sound routine.

How to test in seven nights

Test one variable at a time, otherwise you won't learn anything.

  1. Nights 1 to 3: pink noise, low volume, 45-minute timer.
  2. Nights 4 to 7: no sound at all, with everything else the same — same bedtime, same temperature.
  3. In the morning, note two things: how long you think it took you to fall asleep and how many times you woke up.

Seven nights are enough to see a trend. If there's no difference between the two blocks, sound wasn't the problem.

If the conclusion is the mattress

We have 9 mattresses in our range, all manufactured in Portugal, with 100 nights home trial and 10-year warranty. For lower back pain, I typically suggest the Hisui; for those who share a bed with someone of a different profile, the Takumi (匠, master craftsman). You can see the entire range at Dreamura mattresses. If you're undecided between two, call me — it can be resolved in 10 minutes over the phone (21 150 95 04).

Ana Cristina
Sleep Advisor

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