Little white lies about blue light | Hacker News Reader

Little white lies about blue light

jeremiahlee.com

33 pointsBluestein28 comments

The biggest benefit of Night Shift to me is that warm light is much less painful in a dim room than bluer light. I don't like my wife's car except for one feature: the dashboard lights are all orange rather than the standard white/blue, which is much nicer when driving at night.

If you find light painful it means the light is too bright. Changing the color of the light is a bandaid.

In my experience people use screens which are way, way too bright, and also they use computers in the dark when they shouldn't. Use bias lighting behind your screen. (Of course there are use cases where you want full darkness, like watching movies.)

In the evening on my mac I use 1/16 brightness, and when the room is completely dark my iPhone is set to minimum brightness.

Set your screen brightness such that it matches a white piece of paper put next to it.

That's literally what I do. For some reason I also don't like watching movies in the dark.

Honestly, I think "painful" might not be the right word.

I honestly think the lighting is more mood lighting to me.

The night shift lighting matches a calm down get dim before bed, and the blue light is crisp and bright matching waking up.

I’m sure blue light isn’t particularly bad.

But there’s another side to this: in the late evening/night I set all lights (Philips Hue colour lights) in the bedroom and hallway around the bedroom to go to the darkest orange (no blue). This is what I feel gives a comfortable and usable light with as few lumens as possible. Living room also slow dims to very warm white at lower light levels in the evening. The lack of blue light doesn’t matter in itself, but the lower total light level definitely does.

There’s something deeply psychological about this that I feel trigger a feeling of calmness. It just feels right. Perhaps it has associations to late night bonfires or something. Whether it actually matters if it dims to warm or dims to cool I don’t know.

In this context I also appreciate night shift, just for the fact that the screen better matches the ambient light.

> just for the fact that the screen better matches the ambient light.

This happens by default on Apple devices and it's the second most important computer innovation in the past 15 years, IMO (after retina displays).

> Perhaps it has associations to late night bonfires or something

You might be on to something. There really has to be some evolutionary aspect to it. Also, womb.-

Vox made a little documentary about the relevance of blue light regarding falling asleep. Might be interesting to you: https://www.youtube.com/watch?v=isPxdnIND5k

I'd argue that using the phone has a confounding factor, as in what you're using it for may well affect your readiness to go to sleep for realsies (okay, I don't know if it affects your melatonin levels or not, but melatonin alone going to sleep doesn't make). But if you spend your bedtime reading stress-inducing news pieces, stupid takes on them on social networks, and worst of all, wade into comment sections, prepare to be wrecked, red light or not.

I usually read Wikipedia articles about insects, and it makes me mighty sleepy very easily. Just enough of brain tickling to make it realize it doesn't have the processing capacity, and to get thoughts racing to stop.

author cites less than 5 studies... one of them measures the effect of melatonin supression with 1 hour of blue light exposure. one of the links they posted studies the effects on rats and here's a segment of it,

>Indeed, direct investigations of human circadian resetting reveal that low-intensity, short-wavelength light (460 nm) produces smaller responses than longer wavelength light (555 nm) of equivalent melanopic illuminance [3]. These data are therefore consistent with the circadian effects of color we identify in mice.

feels like a conclusion out of cherry pick & misunderstanding of stuff they read

https://pubmed.ncbi.nlm.nih.gov/21164152/

https://www.sleepfoundation.org/bedroom-environment/blue-lig...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9424753/

https://www.health.harvard.edu/staying-healthy/blue-light-ha...

https://pubmed.ncbi.nlm.nih.gov/30311830/

without digging into all of these, what's the conclusion?

that it's relevant to use a filter/glass after the sunset

or better saying: there's _plenty_ of evidence on blue light supressing melatonin, more than other wavelengths & we know that (melatonin) effects the circadian rhythm, thus, your sleep quality

edit: months ago i was @ a lecture of a neuro-scientist & they talked briefly about melatonin & if i'm not mistaken, changes on your circadian rhythm/sleep patterns don't happen overnight, so blocking blue light/having melatonin pills for a day or a week and expect results aren't the wisest thing to do. but i can't find a paper about this, so take with a grain of salt or ask your closest scientist about it ;)

Hi, I'm the author. I read over 20 studies before writing this post and stand by my conclusion: there is not conclusive evidence blue spectrum light specifically is worse than other illumination.

I only linked to the most interesting outliers that could not reproduce the most cited study's findings. I also linked to the most rigorous study (3 groups: using Night Shift, not using Night Shift, not using phone at all in a natural setting instead of lab) with the largest sample size (167 people) and duration (7 consecutive nights) that found no observable benefit from using Night Shift, only not using a phone before bed.

Here's another rigorous study in a lab setting with similar conclusions: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6561503/

seriously? the iphone study suggest that users stop "consuming" blue light 1 hour before sleep. they don't even control for other substances like coffee or alcohol intake or medication other than "sleep disorders"... your _robust_ ipad study has 12 people...

one of the links i posted is a meta-analysis on the subject that skimmed down ~ 130 studies down to 15 because bad metodology & conclude that blue light has effect on sleep quality

The most important part is "The people who did not use a phone before bed had the highest quality of sleep."

(Am actually considering an external, e-paper, "secondary" phone screen ...)

Do you have a specific device in mind?

Yes. Lost track of it. Will find it ...

Got it!

- https://shop.dasung.com/products/dasung-6-7-e-ink-phone-moni...

This has been consistently my experience -- if I am awake at night and use a phone, I will almost never get back to sleep; reading (on a book or on a frontlit kindle) means that I'll start to feel sleepy and go back to sleep. This is independent of brightness or color of the screen so far as I can tell.

But then again, it's not a great experiment because there are times I reach for the phone and times I reach for a book, and those may reflect the amount of stress or tiredness I feel at the time; i.e. how much interactivity and restlessness I am desiring or experiencing.

The null results I do not find surprising but I would love to see more research on using phones vs. reading vs. e-ink reading and how that influences sleep patterns.

I read in bed on a Kindle and have found that lower brightness is helpful in calming before bed, regardless of whether I have the warmth up or down. The "dark mode" feature that inverts the screen I have actually have pretty poor experience with - I find it harder to read the words which leads to more straining which is counter productive. The only "benefit" I see of this feature is to decrease the overall light in the room which might be helpful for others sharing the bed etc.

>people who did not use a phone before bed had the highest quality of sleep

>This has been consistently my experience -- if I am awake at night and use a phone, I will almost never get back to sleep

these are not the same thing, and this confusion is part of the reason it is difficult to track good information on this topic.

"not falling asleep" is not "low quality sleep", it's simply "no sleep"

also, sleep researchers report that people who think they are insomniac often get a lot more sleep than they think they are getting, so self reports are not that useful.

personally, i would like to wake up an hour later in the morning, hours after I had no trouble falling asleep, and after hours of no trouble sleeping. With all the talk about sleep, I never hear advice tuned to my situation, but the claims are that it does.

But do we have anything to say that phones are a causative factor?

Whilst I don't think this is wrong in the general case, I don't think it's always right either. I commonly watch movies or series on my phone or tablet in bed. Always with a very dim screen and very low volume - and also with night shift on, or whatever it's called.

Sometimes I wake up in the middle of the night to go to the bathroom and can't sleep straight away, so I watch a bit more TV on my phone, maybe up to 1h or so, and then go to sleep again.

Some of my best nights have been that way. 7-8h in total sleep, with screens before and during this time. Some of those nights were so good that I didn't even feel like having a coffee during the day, and didn't feel any sleepiness or fogginess at work.

To me, the 2 things that have the greatest impact on my sleep quality are what and when I've eaten the day before; and how and how much I moved. A long walk is usually enough, whereas strenuous exercise (a long and hard climbing session for instance) can be disruptive to my sleep due to the muscle inflammation.

I personally prefer the warmer tinted screens in the evening, and go so far as a completely red color tint at night, so I’m glad this caught on simply because the option is available on most devices.

However, as it specifically relates to sleep issues, the content of what’s being viewed is likely far more important than the type of light that delivers it. Some political argument that makes you angry, or seeing that your arch-enemy is really happy on social media, is definitely going to affect your ability to shut your brain down for sleep.

Huberman concluded this too - dimming lights at night is better than blue-blocking [1].

I'd like to see a study using Flux on computers for those working late at night and then trying to sleep. Assuming the stimulation of a late work session would diminish sleep quality regardless of light color, but which is "better" at allowing the participant to fall asleep quicker/ higher levels of deep/rem would be helpful. If you're doing anything to do with design Flux is a big no no.

[1] https://x.com/hubermanlab/status/1453746475536510978?lang=en

How about a good dose of both? Both dimmer and warmer light?

No lies, just inconclusive research.

> I prefaced this post with a disclaimer because placebos are effective. I belief they are valid therapeutic options if they do no harm. If the absence of truth helps people sleep better and does no harm, I want the ignorance to provide benefit.

Hmm yeah but spreading lies does do harm.

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