White noise sounds similar to the noise produced by an old-school analog television or radio when there’s no signal.
It’s a sound people used to get rid of as quickly as possible if it started blasting through the speakers.
So why is there a whole industry built around white noise production? And can it really help you sleep or concentrate better?
To understand why anybody would choose to listen to it, let’s first take a look at exactly what white noise is.
What is white noise exactly?
It’s helpful to look at the name itself to start with. White noise gets its name from ‘white light’. In simple terms, white light is all colors, or frequencies of color, combined together.
In a similar way, white noise is a unique type of sound signal that contains equal intensities of all frequencies audible to the human ear, typically ranging from 20 Hz to 20,000 Hz.
20,000 tones
The sound of white noise we hear as humans is the sound of all the frequencies between 20 and 20,000 Hz. So you’re literally hearing around 20,000 different tones of sound all at the same time.
If you think about it this way – imagine you’re sitting in a quiet restaurant. You’ll be able to pick out the individual voices of your companions, and perhaps those on nearby tables.
Now imagine you’re in a full sports stadium waiting for the game to start. There could be thousands of people all talking at the same time, and it will sound like a blurred roar.
White noise has a similar effect. You hear so many different tones all at the same time, it blurs into that ‘hissing’ or ‘shushing’ sound.
It’s also why nature sounds, such as rain, wind, waterfalls, or oceans, are often included on white noise players. There are so many different tones created by those forces of nature, that it turns into natural white noise.
What is pink noise?
The simple explanation is that pink noise is a variation of white noise which sounds deeper, and with less of a high-pitched hiss.
The more complex explanation revolves around why white noise sounds high pitched in the first place.
The reason is that each octave contains twice as many frequencies as the one below it. For example, between 100 Hz and 200 Hz there are 100 distinct frequencies.
But between 200 and 400 Hz there are 200 frequencies. So by the time you get to 20,000 Hz, there are many more frequencies than there were at the lower end of the range.
When pink noise is created in a sound lab, the sound engineers will usually reduce the volume of each successive octave by three decibels to compensate for the extra frequencies.
This balances the sound out by giving more energy to the lower octaves and gives it a deeper sound overall than white noise.
What is brown noise?
Brown noise, sometimes called Brownian noise, sounds even deeper than pink noise, and considerably deeper than white noise. It’s sometimes described as sounding like the deep roar of a waterfall.
It’s not named after the color brown, but after Robert Brown, a botanist who first observed the random movement of particles suspended in a fluid, a phenomenon now known as Brownian motion.
Unlike white or pink noise, brown noise has a power density that decreases six decibels per octave with increasing frequency (or increases 6 decibels per octave with decreasing frequency). This means it has even more energy at lower frequencies than pink noise, resulting in that deep, rumbling sound.
Can brown noise make you lose bowel control?
The famed ‘brown note’ is allegedly a particular low-frequency sound that induces involuntary bowel movements. As entertaining as this urban myth might be, there’s no evidence that brown noise can cause such a drastic loss of control.
Various investigations – from scientific studies to military research and even documentary features – have explored the existence of such a universal frequency. Their conclusion? No singular ‘magic’ frequency with such an unpleasant effect exists.
While certain frequencies might sound very unpleasant to some people, there isn’t a unique sound potent enough to send a crowd rushing towards the restroom.
What is white noise useful for?
Because white noise contains all audible frequencies, its most common use is to mask unwanted sounds. So who might find that useful?
1. Helps you sleep by masking disruptive noises
White noise can be a blessing for light sleepers who are often disturbed by external sounds. If traffic noise or someone’s loud music is keeping you awake, white noise can effectively mask these irritating noises.
For this strategy to work, however, the white noise needs to be at a sufficient volume; otherwise, it will merely soften but not completely drown out other sounds.
Another reason why white noise promotes sleep lies in the nature of our brain: it thrives on stimulation. Nightly noises tend to activate our brain, disrupting our rest. A consistent white noise serves as a satisfying stimulus, preventing overexcitement when sudden sounds occur at night.
If this sounds all too familiar, try experimenting with different types of white noise. If a low rumbling traffic noise is the problem, consider trying pink or brown noise, as they provide stronger resonance at lower frequencies.
2. Aids in soothing babies and improving their sleep
Babies, with their heightened sensitivity to sudden sounds, can sometimes benefit from the use of white noise. It can effectively mask abrupt noises, prolonging their peaceful slumber.
Moreover, the womb isn’t a tranquil place, so babies are already habituated to a steady stream of noise. The hum of white noise can replicate the familiar sound of blood flow in the womb, thereby inducing a sense of comfort and calm.
3. Can help you concentrate – for a while
While writing this article, I’ve been listening to pink noise constantly. I can hear the sound of traffic quite loudly from where I work, but the pink noise completely drowns it out.
This keeps distractions at bay – the fluctuating traffic volume, roaring motorbikes, thunderous trucks, and blaring horns are all silenced.
I find it’s very effective and I’m so used to the sound now that as soon as I put it on I feel focused, and it fades nicely into the background.
It’s also sometimes used by people who work in other kinds of noisy environments, such as manufacturing or where there’s a drone of technological devices.
Despite my positive experience with white noise, some studies have suggested continuous white noise usage might negatively impact performance, stress levels, and memory.
Research into whether white noise boosts concentration in children with attention difficulties have yielded mixed results; it seems to aid some, while impairing others who lack attention issues.
The verdict is still out then. Personally, I find white noise preferable to persistent traffic drone. Given more time, however, it may morph from a soothing background hum to just another annoying noise.
4. Helps in mitigating tinnitus
Speaking from personal experience, I can confirm that white noise can offer relief from tinnitus. Following a chemotherapy regimen for cancer two years ago, tinnitus emerged as a lasting side effect of the drug Cisplatin in my case.
The condition tends to intensify at night or during periods of fatigue, illness, or stress. In these moments, white noise – be it pure or nature sounds – provides an effective remedy, helping to suppress the ringing I hear because of the tinnitus.
5. Promotes relaxation
Many people find the sound of oceans, rivers, waterfalls, or rain relaxing and peaceful. It may not be for everyone, but most people will state that one of the joys of being in nature is listening to the sounds.
So the next time you’re feeling stressed, why not have a listen to the sound of an ocean or waterfall and see if it helps you unwind?
Can white noise genuinely enhance sleep? What the research says
A number of compelling studies have delved into the potential of white noise to improve sleep quality. These investigations often target specific populations, like newborns or adults in noisy hospital settings. Nonetheless, they’ve unveiled some intriguing positive findings.
Adults in noisy New York
In 2021, researchers undertook a study into the effects of white noise on the sleep of New Yorkers.
It was only a small-scale study involving ten people, but it’s an interesting one as they recruited participants from a sleep clinic who reported noise as being a factor in their sleep problems.
The researchers found that both subjective and objective measures showed improvements in sleep in the group that was exposed to white noise.
I’ve previously reviewed the device they used – the Dohm Classic. It’s not a loud white noise machine, one of the quietest in fact. So it’s interesting that they had such positive results from a relatively gentle white noise machine.
Adult patients in a critical care unit
In 2016, researchers in Iran undertook a study to see if white noise would help patients in a critical care unit sleep better.
The patients were divided into two groups. One group was exposed to white noise at 50-60 decibels, while the other group experienced the standard sounds of a hospital ward.
At the onset, no discernible difference in sleep quality was observed between the groups. However, after three days, those exposed to white noise reported significantly better sleep than the control group. Their conclusion was as follows:
Sleep disorders are more common among patients in intensive care units. Environmental factors like noise is a common cause of sleep disorders. Based on the findings of this study, the use of white noise is recommended as a method for masking environmental noises, sleep induction, improving sleep, and maintaining sleep in the coronary care unit.
Adult patients recovering from heart surgery
In a study conducted in 1992, a researcher at Huntsville Hospital in Alabama examined the effects of white noise on the sleep of patients recuperating from heart surgery.
For this study, 30 patients were played ocean sounds via a white noise machine, while another 30 were exposed to the typical sounds of the ward.
They found no difference in the groups’ sleep latency – the time it took to fall asleep. However, the group listening to white noise reportedly had better overall sleep. This was based on better results for ‘sleep depth, awakening, return to sleep, quality of sleep, and total sleep scores’.
The researcher’s conclusion was as follows:
The use of ocean sounds is a viable intervention to foster optimal sleep patterns in postoperative CABG patients after transfer from the ICU.
White noise reduces the effect of changing noise levels in an intensive care unit
In 2004, a study was conducted to determine whether the volume of environmental noises, changes in that volume, or both were more disruptive to sleep in an intensive care unit. The study also explored if white noise could mitigate this disruption.
Interestingly, the researchers used Polysomnography – the gold standard of sleep monitoring – rather than relying on subjective or observational measures of sleep.
The findings revealed that white noise helped by minimizing the disparity between the usual background noise and louder, abrupt noises:
Peak noise was not the main determinant of sleep disruption from ICU noise. Mixed frequency white noise increases arousal thresholds in normal individuals exposed to recorded ICU noise by reducing the difference between background noise and peak noise.
This study holds particular significance as it corroborates one of the central assertions about white noise – its capacity to prevent sudden external sounds from waking people up during sleep.
Newborns
Arguably, the most famous study concerning white noise and newborns was conducted in 1990.
The research, carried out at Queen Charlotte’s Hospital in London, evaluated the effects of white noise on newborns aged between two and seven days.
The newborns were divided into two groups of 20. One group was monitored in silence in their cots to determine how long it took for them to fall asleep.
The second group was exposed to white noise played through a standard white noise machine (positioned adjacent to the cot, 30 cm from the head).
It was observed that 16 (80%) of the newborns fell asleep within five minutes when exposed to white noise. In contrast, only 5 (25%) fell asleep within the same timeframe in the absence of white noise.
Moreover, the researchers noted two fascinating findings. Firstly, noise at lower frequencies, similar to the hum of a vacuum cleaner, proved more effective. Secondly, white noise didn’t assist in soothing the infants if they were hungry but proved beneficial once they had been fed.
Addressing safety concerns when using white noise for newborns
This next study didn’t examine the effectiveness of white noise, but I think it’s useful to go off on a brief tangent to look at the safety advice arising from it.
In 2014, a study by researchers at the University of Toronto gained international media attention, with coverage in outlets such as New York Times.
The study examined a selection of white noise machines, revealing that several had a maximum volume level that could potentially harm a child’s hearing.
The primary point made by the researchers wasn’t to condemn the use of white noise, but rather to advocate for manufacturers to provide clearer usage guidelines to ensure safety.
They concluded:
ISMs (Infant Sleep Machines) are capable of producing output sound pressure levels that may be damaging to infant hearing and auditory development. We outline recommendations for safer operation of these machines.
Guidelines for the safe use of white noise
As well as urging manufacturers to lower maximum output, incorporate safety warnings, and embed auto-off timers, the researchers also provided a set of useful guidelines for parents:
1. Place the ISM as far away as possible from the infant and never in the crib or on a crib rail.
2. Play the ISM at a low volume.
3. Operate the ISM for a short duration of time.
What these studies collectively suggest is that scientific evidence backs up the potential of white noise in enhancing sleep for certain adults and newborns.
However, if you use it to help children sleep, it’s important to do so in a safe way. Don’t play white noise at a loud volume or for extended periods of time, and aim to avoid developing a reliance on it for inducing sleep.
What do sleep experts say?
The National Sleep Foundation says that noise at night can wake you briefly, especially during the lighter sleep stages. So they suggest that white noise can help “mask activity from inside and outside the house”.
They also report that in their large sleep survey in 2012, 74% of Americans rated a quiet bedroom as being important for sleep.
Dr. Rebecca Kempton, M.D., a pediatric sleep specialist writing on her website babysleeppro.com, advises parents to use white noise.
She asserts that babies, accustomed to the noise within the womb that’s nearly as loud as a lawnmower, may find white noise more soothing than silence.
What do manufacturers say?
As you’d expect, the companies that make white noise machines all speak highly of the potential for white noise to improve sleep.
On the LectroFan website, for example, there’s a suggestion that it helps with noise changes:
When a noise wakes you up in the night, it’s not the noise itself that wakes you up, per se, but the sudden change or inconsistencies in noise that jar you. White noise creates a masking effect, blocking out those sudden changes that frustrate light sleepers, or people trying to fall asleep.
They also explain why it can be helpful for babies. They point to the ‘shushing’ sound that parents naturally make to calm their babies, explaining that white noise is a way of ‘outsourcing’ your shushing.
The company behind LectroFan also believes that white noise creates a safe environment by blocking out noise that can be overstimulating.
It reduces the number of sudden disturbances from siblings, TVs, and music. And that it can help babies stay asleep longer by extending how long it is before they experience natural arousals.
Yogasleep (formally Marpac) says on their website that white noise can help if snoring keeps you awake, or if you live in a loud environment.
They suggest that it provides a consistent sound environment that is especially soothing to infants, but also for adults.
They also propose the interesting idea that parents can continue normal activities without tiptoeing around the house.
My personal experience
I have to admit that I tend to sleep best when I have absolute silence. My solution is usually to use earplugs and shut the world out as much as possible.
However, earplugs don’t always do the trick – they can only reduce so much noise. So on occasion, I’ve played pink noise (I find the lower frequency more relaxing), as I find it does a great job of blocking out noise.
However, I have to play it on as low a volume as possible, so as not to find it more disturbing than the original noise. And recently, I’ve discovered that white noise in the form of natural sounds, like rain and waves, also helps me relax and fall asleep.
Your views
Do you listen to any type of white noise to help with your sleep, work, or studies? What kind of white noise do you find works best? Let me know in the comments below!
I am concerned about starting the use of any noise-generating machine to help me stay sleeping through the night, and during napping. My question is won’t I get so accustomed to the white or pink noise that I will get “hooked” on it? My audiologist says you use it, then ween off and somehow that works, but I am skeptical.
Hi Christine
Thanks for your comment. I think it’s possible that you can end up struggling to sleep without if you remove it. I have the same problem with earplugs! But I also see it in a purely practical way – I couldn’t sleep with noise before, so why should I suddenly be able to sleep with noise again after having a nice blissful period of no noise? Perhaps with some therapeutic intervention to find a way to stop noise bothering you, the whole weaning off idea might work. But for me personally, I struggle to believe that there is a way to learn to sleep with noise unless I’m so utterly exhausted I can still sleep. But on an average night, if earplugs, music or white noise do the trick, I’ll take it!
I know there are some arguments against using white noise every night, especially on a loud volume. Personally, I’d use it on a low volume, position it away from your ears, and switch between nature sounds too like waterfalls and rain. Better that than very loud intense white noise for hours on end blasting your ears.
Regards
Ethan
Hi Ethan,
Just found your website now because I’m trying to understand how these colored noises affect the brain and sleep.
Brief background, I’ve been using earplugs at night to get rid of the noises that my flatmates make all night long, esp. those 2 rooms on both sides of my room. A couple of years ago, I first tried white noise by turning on the radio loudly without frequency, that didn’t mask the banging of doors and kitchen noises, So I then used earphones to listen to white noise and turned the volume high a bit to mask the annoying external sounds. Initially It helps with me falling sleep because it deactivates my hyper active brain, but in the morning I always have a tinnitus. For a couple of months I did that, but it came to a point that the tinnitus is becoming stronger, so I stopped and relied on disposable earplugs instead. For a year, I’ve used earplugs but this has effects too, like dried ear canals and itchiness that wakes me up in at night. I remedied the itchiness by cotton swab with petroleum jelly to clean my ears every 2 days, that also extended the life of the earplugs and I didn’t have to throw it even after 5 days of use.
But recently, about 2 months ago, I was so stressed at work and developed anxiety that kept my brain active at night, thus making me only sleep 2 hours every and the vicious cycle started – wanting to sleep but cannot because of fear of not getting enough sleep made me awake due to conscious sleep monitoring.
So last night, in desperation, I turned back to the noise, brown noise in my case. I had the amazing, energetic sleep I didn’t have in months! I didn’t turn the volume up too much to avoid the tinnitus, and I now can attest that colored noises are working for me to shut my brain up at night. It also makes me concentrate / focus better at work (this I’ve proven years back when I started listening to white noise, I didn’t have that headache that other are complaining about).
Btw, those soothing rain / spa/ thunderstorm noises didn’t work for me since I tend to listen to the ever changing noise instead of letting my brain shut down.
Hi Gray
Thank you for your comment. It’s not easy to deal with noisy flatmates, unfortunately. One trick you could try is to put more fabrics and furnishings in your room – hang some material, put in a rug, get more cushions, pillows etc. Basically anything to absorb the sound energy. Then maybe try putting underlay or neopreme under your bed legs too to reduce the sound travelling that way.
As for ears, be careful using swabs. I use earplugs regularly, and always throw them away after a couple of days rather than risk a build-up of dirt in my ear. And I also like brown noise compared to white noise. Like you say, keeping it on a lower volume is better – and safer.
Regards
Ethan
Newer studies show that white noise is actually detrimental to the brain. Much healthier is to use noise that varies in pitch and frequency, mimicking the natural world (and conversations).
Hi Diane
Thanks for your comment. Could you give me some links to these studies please? I know there have been some waves about not using white noise too for long periods of time or at loud volumes. But I don’t think it’s the case that it shouldn’t be used at all.
Regards
Ethan
Absolutely agree with you on this. I have been exposed to white noise at my place of employment for several weeks and up to several months on and off. At times the white noise speakers around me sounded very loud, I’ve developed headaches overnight, a pressure sensation in both my ears, tingling and several other effects that I can only relate to the technology being used.
Eventually, the speakers were turned off due to numerous complaints of having to hear the constant hissing sound (noise really).
Since then all for me has returned to normal and what I was experiencing is completely gone now. The effects took about a week to disappear completely. The technology may be good for some but not others. Perhaps those with supersensitive hearing will experience what I did. Not sure what others think about it but it was definitely affecting me.
Since then I have moved to a new office location and they have speakers emitting white noise all day. I have opted to use a set of noise muting headphones to block all sounds including speech. This seems to work fine for me since I don’t hear anything now as long as I have the headsets on.
If I don’t have them on because I am on the phone or talking to someone, I hear the white noise speakers in the background.
I try not to stay sitting all day in front of my computer but even that may be perceived as not being productive.
Advice for corporations out there, Implementing technologies should be thoroughly researched before they are implemented in the workplace.
Hi SB
I can imagine listening to white noise all day would be a bit much. I quite like it for a couple of hours on an occasional day if there is annoying noise outside my study. But every day all day would drive me up the wall!
Regards
Ethan
Really, for me it is the varies in pitch and frequency which actually wake me up especially conversations! The white noise which helps me sleep is a very low humming sound much like the brain wave frequency.
Very different for my mother and husband who readily fall asleep in front of the television. Oh how I envy them!
We have white noise in the office. It plays all day long and it doesn’t cut out the sounds or people talking since it travels down the hallways. What’s more annoying is that it’s programmed at intervals and I can even tell the time. It’s on very soft at 8, then up one level at 8:15 and then up another level at 8:30 and stays constant for the rest of the day. Everyone in the office is okay with it (or people are afraid to say something) so makes me think I’m the crazy one? I feel I’m working in a Coke bottling plant with the constant roar of the conveyor belt. I think it might be the pitch since the desk fan I have doesn’t bother at all. My dentist installed white noise in their waiting room and I stopped going to their office a few years ago. I really, really and truly hate white noise!
Hi Xiao
Thanks for your comment. I can understand why you’d hate it if you have to listen to it all day! It would drive me crazy if I had to listen to it all day every day. Why did they install it as a permanent feature?
Regards
Ethan
Many of the hospitals installed it in our area and the boss thought it was a great idea to install it in our office as well. Funny thing is that none of the speakers are installed near their office doors so they don’t have to listen to it. They claim that it cuts down on the noise coming from other people when they are on the phone but I think it makes them talk a little louder.
Hi there
Yes, that might be the reality of using white noise in the office if it’s not properly thought out! Personally, I wouldn’t be too keen on having it constantly on in the office all day, every day!
Regards
Ethan
I agree with Lyn. How is possible to someone to get a better sleep listening to white noises? And, poor babies! It is a mere combination of unpleasant sounds. There are better and soothing choices to provide nighttime relaxation. Yes, the world
of science definitely went mad – as Lyn said. She is totally correct.
I hope you provide more sources to find white noise besides the free apps. Dr. Harvey Karp (“The Happiest Baby on the Block”) highly recommends “harsh, rumbly” white noise for all babies’ naps and nights at least one year and under. It has helped us greatly in getting our babies to sleep many times. So two things I want to say here:
1) I recommend the “Sound + Sleep” machine you can find on Amazon. It is about $100 but very well worth it. You may want to publish info on the Dohm sleep machines as well.
2) My husband really struggles with the white noise. He says it gives him dreams when he used to never have them, as well as headaches and ringing in the ears. (He and I have never had any trouble sleeping). We still have two very small children, but I have recently turned it off at night with the sleep timer (on the Sound + Sleep machine–it has 4 sleep timer settings to avoid disruption of a sudden “off). Now, he and I both feel very refreshed again. It was almost a complete noticeable difference for us in how we felt. With the white noise on every night, we were feeling groggy and exhausted almost all hours of the day. I always felt as though I couldn’t get enough sleep. Can you research whether white noise can make some people MORE tired? I wonder if it’s because our brains were engaging with the sound from the machine and keeping us from deeper sleep. Our house and area is very quiet, so we weren’t struggling with outside or street noises. It IS helpful to block out household noise or crying from the other children especially during the daytime or evening when others are awake.
If it made US feel more tired, I still worry a little about the babies not being refreshed after naps. I’m not sure!
Hi Kendra
Thanks for your comment. That’s the reason most machines have an auto-off timer! The idea is that they help mask noise when you’re falling asleep, but don’t then become the reason you wake up later. I’ve seen some good advice – especially for using it with children – saying play it at the softest volume for the shortest possible time.
Regards
Ethan
I don’t know how anyone could listen to white noise for long periods as I believe my neighbour is using some kind of white noise sound and it’s driving me nuts, my ears ache, I can’t sleep properly and when I do I wake up with headaches. I know it’s not in my head because I have recorded the noise to prove I’m not loosing my marbles or that I have tinnitus. Why would anyone find it relaxing and those poor babies, has the world of science gone mad or am I just losing the plot.
Hi Lyn
Thanks for your comment. There must be something unusual happening if you can hear white noise that loudly through a wall. Perhaps they are playing it loudly on a stereo, because no small device or phone would be loud enough to both go through a wall and cause someone else trouble. I would speak to them and ask them if they wouldnt mind playing it softer. You could also politely suggest that there is advice from specialists who say it should be played to young children as quietly as possible and still has the desired effect.
Regards
Ethan