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LED lighting badly suppresses human melatonin production at night

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Re: LED lighting badly suppresses human melatonin production at night

#181

Post by KaiserPro »

zachruss92 wrote: post #7
000ooo000 wrote: post #5

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.

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 produce soot which has much more significant data to indicate that it is detrimental to your health.

Blue light(instead of just lumens) has much less evidence.

Re: LED lighting badly suppresses human melatonin production at night

#182

Post by KaiserPro »

Syonyk wrote: post #45
khazhoux wrote: post #38

Earlier quoted context omitted.

Indeed, even after reading several of the studies cited here and elsewhere, this whole idea of blue light > specialized photoreceptors > melatonin production > sleep (not to mention cancer ) seems like just correlations stacked on top of each other. I understand that some people have problems sleeping, but saying blue wavelengths are a general hazard to sleep (not to mention cancer ) is absurd.

What's your problem with the links in that chain? We know (or, at least, papers argue...) that all of the linkages are true, and I (post author) link some studies that look at the end-to-end results - blue light vs sleep. With what I consider to be fairly straightforward results. I write having spent the last few months testing exactly this sort of thing in my life. Nights spent with LED lighting, or LED lit screens,…

> "Reading a book on paper by lantern light" vs "reading the same book on Kobo by frontlight" is the same mental activity.

How many times brighter was the light emitted from the ebook compared to plain paper?

We know that not getting sleep is bad, we know that bright lights affect sleep.

For this study to be convincing we'd need a number of things:

1) more than 12 people to take part.

2) Spectra controlled but the same overall lux level in the room. Both booth and ebook emitting/reflecting the same number of lumens.

Re: LED lighting badly suppresses human melatonin production at night

#184

Post by soco »

steve1977 wrote: post #156
koverda wrote: post #107

Regarding the quoted e-book study: > Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light. Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your e…

This. If I set my reading devices to maximum brightness, I can basically use them as flashlights.

When you wake up at night in pitch dark, a Kindle does already a perfect job to help navigate around - and won't hurt your eyes either.

Re: LED lighting badly suppresses human melatonin production at night

#185

Post by londons_explore »

koverda wrote: post #107

Regarding the quoted e-book study: > Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light. Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your e…

I am disappointed that many phones/tablets don't go very dim.

From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting.

I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithmic, so dividing the brightness by 1000 doesn't have as much visual impact as you'd expect).

Re: LED lighting badly suppresses human melatonin production at night

#187

Post by kzrdude »

marcell wrote: post #79

There is always a time lag between the introduction of a cool new technology, and the discovery of its negative effects on human health. 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. Ciga…

Fun fact: leaded fuel was known to be detrimental to health when introduced in 1924, but it was good for the bottom line so it was done anyway. It can still be said to follow the trend of introduction and then (much later) being discredited and remedied.

Re: LED lighting badly suppresses human melatonin production at night

#188

Post by nashalo »

For those of you who have an iPhone, a handy feature that helps with phone lighting at night is "Reduce White Point" in accessibility features. It is different than night mode and reducing luminosity to the minimim and I find it's a nice addition. You can put it in the control center for fast enable/disable should you need it. I have trouble sleeping and I found this helped, albeit marginally.

Re: LED lighting badly suppresses human melatonin production at night

#189

Post by greggsy »

londons_explore wrote: post #185
koverda wrote: post #107

Regarding the quoted e-book study: > Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light. Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your e…

I am disappointed that many phones/tablets don't go very dim. From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting. I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithm…

It’s possible to set a custom filter in iOS, which reduces the brightness even further, but only in one colour, ie red. Better than nothing.

The main issue i think is that backlights tend to flicker at low brightness.

Re: LED lighting badly suppresses human melatonin production at night

#190

Post by kzrdude »

There's a lot of talk about bright light, but for me it seems like there is actually something else at play that's worse.

For me, it's the incessant stimulation from social media, youtube, internet, etc that keeps me awake. It's this "just want more" loop in the brain. If I just read a book the last hour when I want to fall asleep, then I usually do, while if I would stay on a loop with the computer or phone then I can't sleep.

If something is sufficiently stimulating (like an unfinished programming problem or playing factorio can be), it can somehow put my brain in a high gear where it refuses to calm down for hours, so these two hobbies are very detrimental to sleep as well.

I hope I'm not exaggerating: it seems like this focus on light could be useful, but in a way it is a distraction from some even bigger problems. If only it was as easy as toggling for dim light!

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