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LED lighting badly suppresses human melatonin production at night

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241–250 of 316 posts

Re: LED lighting badly suppresses human melatonin production at night

#241
Since this topic is related to the circadian rhythm, here’s my understanding of optimizing that (aside from lighting):

- No coffee 6-8h before sleeping. I try to keep it to before noon. Having a strong coffee at 3PM often means I stay up til 2AM.

- Digestion should be done-ish before sleeping. A rule of thumb seems to be not eating no heavy meals past 3PM. Or at least 6PM. For me, a big amount of protein for breakfast helps keeping hunger in the evening down. (You can find great discussions and small studies if you search for „eTRF“ on Reddit)

- Breakfast resets the circadian clock. Some people can’t eat before 10AM which is probably ok. I‘ve found that I can train myself to eat earlier, it’s a process.

- A bit out there - Creatine has been found to help sleep deprived people - not sure why that is, but I‘ve been testing this lately. Maybe it helps with circadian rhythm, maybe not.

- More about sleep than CR: An air filter near the bed improved my sleep quality by so much. I got a big one from Coway but it probably doesn’t matter much which one.

Re: LED lighting badly suppresses human melatonin production at night

#242
post #221
post #203

Earlier quoted context omitted.

iOS actually has a hard to find setting that lets you make the screen super dim. It's been a lifesaver when using my phone in the evening. To enable it go to Settings -> Accessibility -> Zoom and then tap the Zoom toggle switch. Once that's enabled iOS will now bring up a super secret popup menu whenever you double tap the screen with three fingers. From the little popup menu go to Choose Filter -> Low Light and your…

For what it's worth, as far as I understand, you actually need to activate the Zoom Controller to get the menu mentioned above.

I just tried this out. Turned on zoom, without the controller, couldn’t get the menu when three-finger double-tapping.

However, when I three-finger triple-tapped, the menu showed up.

Re: LED lighting badly suppresses human melatonin production at night

#243
post #223

Earlier quoted context omitted.

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…

A Macbook's minimum brightness is quite bright. The thing that annoys me no end is that if you hit the "dim" button when it's at minimum brightness, it goes black - but fades out slowly and smoothly. So they're clearly capable of being dimmer, but Apple decided we're not allowed that.

Been a while since I used a MacBook but can't you do Shift+Opt (or just Opt?) Brightness+/- for an incremental change still? Works with volume too.

Re: LED lighting badly suppresses human melatonin production at night

#244

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 c…

actually, there are visual receptors in the eye which are directly tied to the hormonal center of the brain. Red/Infrared light is stimulating Melatonin and blue/bright light triggers Cortisol production.

Arguably, this is linked to the circle of the sun and a lifestyle that is heavily bound to sunlight.

Re: LED lighting badly suppresses human melatonin production at night

#245
post #238

I am a big fan of LEDs but the strobe effect is maddening and it only gets worse as they are dimmed. AC power crosses zero volts with every cycle so you need a driver circuit that can compensate. Most don't do a good job and I have replaced bulbs and dimmers multiple times to come up with something acceptable. At the family camp, I retired my kerosene and propane mantle lamps in favor of solar battery powered LEDs ma…

Interesting comment. I have a number of MR16 bulbs in my house that were previously halogen and are now mostly LED. They are a near constant source of frustration with bulbs burning out way too soon, some with what seems like wiring issues, a mix of incompatible switches, etc. Curious to hear what acceptable solution you derived?

Are they low-voltage lamps? (usually have a GU5.3 base). If they are powered by old transformers intended for halogen lamps it might be worth changing the transformers to ones meant for LEDs.

Incidentally if there are dimmer switches in the circuits then those might have to be changed too.

Re: LED lighting badly suppresses human melatonin production at night

#246

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…

Yes, thank you for being rational. "Yorg, turn down the campfire or we'll never get to sleep!"

actually, infrared light from campfires improves sleeping quality because it triggers melatonin production in the brain. In contrast, blue bright light triggers cortisol production.

Re: LED lighting badly suppresses human melatonin production at night

#247
post #203

Earlier quoted context omitted.

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…

iOS actually has a hard to find setting that lets you make the screen super dim. It's been a lifesaver when using my phone in the evening. To enable it go to Settings -> Accessibility -> Zoom and then tap the Zoom toggle switch. Once that's enabled iOS will now bring up a super secret popup menu whenever you double tap the screen with three fingers. From the little popup menu go to Choose Filter -> Low Light and your…

THANK YOU! I have wanted this since forever. I can't believe this is locked away so deeply and inconveniently.

Re: LED lighting badly suppresses human melatonin production at night

#248
post #229

Earlier quoted context omitted.

They do... But thats down to poor design decisions. Human vision extends from about 10^5 cd/m^2 to 10^-5 cd/m^2 [1]. Typical backlights use something like PWM to modulate the brightness. That means you need to be able to scale your backlight by a factor of 10^10 to cover the whole human vision range. And if your CPU runs at 1 Ghz (10^9), then at the dimmest setting then even being on for a single clock cycle would be…

> That means you need to be able to scale your backlight by a factor of 10^10 to cover the whole human vision range. Uh, phones don't produce brightness that high. And the low range is "too low" for usefulness anyway. Your math is off by few factors > And if your CPU runs at 1 Ghz (10^9), then at the dimmest setting then even being on for a single clock cycle would be a flash every 10 seconds - clearly unacceptable,…

Unfortunately at these low currents, you tend to get a tiny amount of leakage across the LED junction - just a few microamps, but trying to make a small amount of light it becomes an issue. Worse, you can't even calibrate for it because the leakage is highly temperature dependant.

Re: LED lighting badly suppresses human melatonin production at night

#249
post #154

Earlier quoted context omitted.

I'd worry about what else is in the one that helps you sleep to cause there to be a difference.

Or perhaps there is something lacking in the brand that does not help them sleep? By that I mean maybe there is less creatine than claimed, or it is supplied in a form that is harder to digest.

Really hard to know, but the creatine that didn't seem to help was a cheaper, bulk buy. My guess is that it wasn't as much creatine as it said. Unfortunately, I feel like there is a lot of misrepresentation around supplements.

Re: LED lighting badly suppresses human melatonin production at night

#250
post #243
post #223

Earlier quoted context omitted.

A Macbook's minimum brightness is quite bright. The thing that annoys me no end is that if you hit the "dim" button when it's at minimum brightness, it goes black - but fades out slowly and smoothly. So they're clearly capable of being dimmer, but Apple decided we're not allowed that.

Been a while since I used a MacBook but can't you do Shift+Opt (or just Opt?) Brightness+/- for an incremental change still? Works with volume too.

I never knew this. Thank you for the tip.
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