71–80 of 316 posts
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He also did an interview with a person from the NIMH who personally only uses candle light past dark. It makes sense when you think about it. Also apparently overhead lights are worse- the angle makes a difference.
Candles also supposedly awful for PM 2.5
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A lot of people over the age of 40 or even 35 are going to have trouble reading a physical text from a comfortable distance in light dim and warm enough not to affect one's circadian rhythm. Though I see your points and agree with aspects of this piece I also really struggle to see how a dim light close to your face is objectively worse than lighting your entire room in order to read a book and think extreme statemen…
I'm in that age group (post author) - over 40. I've experimented with self-lit screens vs lantern lit {books, e-ink screens} vs overhead incandescent bulb lit {books, e-ink screens}. The results are clear. LED lit screens are awful for my sleep. But we disagree on a major point about LED screens being "inevitable." That is, certainly, the current cultural default. No question. But I also know a lot of people who are…
Andrew Huberman of Huberman Lab podcast discusses this in the first 4-5 episodes of the podcast. The takeaway is: it's late-night bright light, rather than blue light, that has effects on the circadian rhythm. It's an appeal to authority but I think I'll go with the professor of neurobiology and opthalmology on this one.
(Post author here, huh, it hit HN...) This is not consistent with the studies I've read. It's a "total lumineous flux in the 460-490nm range" concern. The deep reds, up past 600nm, don't seem to have any impact on melatonin, nor do violets below ~420nm - though they can have other impacts on the retina and such. Bright light will, all other things being equal, be worse than dim light, but "dim blue light" is still re…
I buy dim bulbs that have a temperature of 2700K for evening applications precisely because of this belief that brightness and color impacts sleep quality, am I right or is it just placebo? It seems to help...
There are also probably very personal and biological variables involved too that the post doesn't mention. I stare into monitors and phones all day long. Every light in the house is full-blown LED. I can't help but fall asleep at 20:00 in an led lit room watching led TVs, while my led phone drops onto the floor after I've fallen asleep. I've been in an extreme LED environment for over a decade and never have problems…
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It looks at the emitted energy from the screen. The ebook emits directly, a foot from your face. The paper book is reflected energy, at a rather higher reflectance and a rather lower energy. It's amazing how dim a light you can read a paper book in vs an e-ink ereader.
Photons are photons, reflected or not. So what prevents the ebook to lower the brightness of backlight to match the energy of the reflected light from a paper book? (For e-ink ebook readers, can't they just be read without backlight, with just reflected light?)
Usually you need more reflected light to read from e-paper because of worse contrast.
The new EU light labelling requires a spectrum to be posted online. This bulb still has a blue peak, but it is mainly red:
https://eprel.ec.europa.eu/screen/product/lightsources/84738...
The bulb dims well without flickering, but my only complaint is it doesn't dim that much. This seems to be the case with all ZigBee bulbs I've tried. A Philips Warmglow with a separate dimmer can be dimmer smoothly from off. Does anyone know why ZigBee bulbs don't do the same?
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(Post author here, huh, it hit HN...) This is not consistent with the studies I've read. It's a "total lumineous flux in the 460-490nm range" concern. The deep reds, up past 600nm, don't seem to have any impact on melatonin, nor do violets below ~420nm - though they can have other impacts on the retina and such. Bright light will, all other things being equal, be worse than dim light, but "dim blue light" is still re…
Since you seem super duper into this, you could try what I do on many evenings even just as an experiment. I just strap on a very nice LED headlamp that has a pure red LED that I use for "night mode". That it uses way less power is actually just a side effect of me wanting all the blue lights off at night. I know it's not for everybody, but I find it really relaxing. The trick is to get one that's not a joke lamp fro…
Earlier quoted context omitted.
(Post author here, huh, it hit HN...) This is not consistent with the studies I've read. It's a "total lumineous flux in the 460-490nm range" concern. The deep reds, up past 600nm, don't seem to have any impact on melatonin, nor do violets below ~420nm - though they can have other impacts on the retina and such. Bright light will, all other things being equal, be worse than dim light, but "dim blue light" is still re…
Ooh the post author! I have a question. When I buy light bulbs they always list the color temperature but not the lumineous flux, what's the relationship? I buy dim bulbs that have a temperature of 2700K for evening applications precisely because of this belief that brightness and color impacts sleep quality, am I right or is it just placebo? It seems to help...
Anyways, hopefully a real expert chimes in. :)
DDT was invented in the 1940's, and it wasn't until twenty years later that people discovered its negative effects through bioaccumulation. Teflon was invented in the 1930's, and it again took decades to discover its negative effects on human health, apparently under high heat. Cigarettes: decades until we knew scientifically they were bad.
Just a couple days ago there was a thread on HN about low sperm counts, with a lot of hemming and hawing about whether or not the effect is real. Here we have a claim that LED affects sleep cycles and melatonin production. We know testosterone production is related to sleep quality. Are these two related? We also have observed early puberty in girls. It went up during the Covid pandemic, when screentime increased for all school age kids in America. Is there a link between early puberty, LED screens on computers, and dropping sperm counts and testosterone levels?
We don't know scientifically. Expect to find out in two decades, when its too late for you to do anything about it!
Andrew Huberman of Huberman Lab podcast discusses this in the first 4-5 episodes of the podcast. The takeaway is: it's late-night bright light, rather than blue light, that has effects on the circadian rhythm. It's an appeal to authority but I think I'll go with the professor of neurobiology and opthalmology on this one.
I’m surprised to see him championed here. He pops up on my Twitter feed sometimes and as a scientist myself, he comes off as an absolute quack. Dr. Oz for millennials and zoomers that think they can fix everything with the right supplements, red light therapy, and daily affirmations, with very little real evidence behind it. A good summary here- https://www.reddit.com/r/podcasts/comments/rpu1b4/any_opinio...