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Comment by unshavedyak | Hacker News Reader

Do we know why outdoor lighting helps? I’ve seen people recommend super strong indoor lighting for various health impacts, would the at affect eyes?

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Full midday sunlight is about 100,000 lux. Recommended illumination levels for office buildings are 300-500 lux. Domestic rooms will often be lit at less than 100 lux.

My workbench is illuminated to 10,000 lux, which compares to common daylight conditions. Just lighting that small area requires 120 watts of high-efficiency LEDs. Lighting the whole room to that level would require nearly two kilowatts of LEDs. Most "super strong indoor lighting" is in fact very dim compared to sunlight. We don't realise it, because our visual system is incredibly adaptable to changing illumination conditions.

I feel like it's not directly comparable because light gets reflected around indoors. I imagine having full sunlight indoors would turn everything white.

Illuminance (lux) is a measure of the amount of light falling on a surface, not the amount of light being emitted. Any reflected light will count towards the measured illuminance.

Sunlight is just incredibly bright. There's a reason why film crews often need to use huge metal halide lamps powered by a generator truck - it takes an immense amount of power to compete with daylight.

https://en.wikipedia.org/wiki/Illuminance

https://www.arri.com/en/lighting/daylight/arri-daylight-18-1...

You can just use a light meter to measure directly.

Normal indoor lighting is a few hundred lux and with the right setup, I was able to increase it to 1000 lux at where my head is generally physically located.

How much of this is related to very bright light versus IR? Compared to incandescent light, LEDs have little IR.

This is my concern as well, I think the preponderance of LED lighting could be causing more Myopia because of less IR and perhaps UV

Wouldn't the indoor light have to be strong enough to make you want to wear sunglasses indoors?

You would probably have to put stage lighting in your house to get the same affect as being outside. My eyes behave pretty different and seem to get a "workout" when I am outside in sunny weather.

I imagine you'd be able to wear the same thing you do outdoors. Which is to say, i don't wear sunglasses outdoors.

But regarding the lighting itself, yes i do think it is similar to stage lighting (brighter, i assume). Thermal and power is a significant concern with the lighting iirc, but i'm not too familiar. If i recall correctly the post that advocated these as a video and had an explanation on the difficulties. It heated up the room significantly.

With that said i want to stress that this was some post i saw several years ago, and i can't seem to find the video anymore. Iirc the lights were insanely bright, though.

I briefly took up a hobby of trying to raise some tomato plants indoors. The lights that claim to emit the full spectrum of non-visible light to match sunlight are insanely expensive (thermally and otherwise). There's probably more to the sunlight's effects on dopamine production than lux.

Many years ago I had a coral reef aquarium. The lighting required was the biggest expense and challenge to place and keep cool.

Possibly unrelated, but a specific frequency of infrared light has been found to have a protective and possibly even regenerative effect on aging eyes.

"Upon transcranial delivery, NIR light has been shown to significantly increase cytochrome oxidase and superoxide dismutase activities which suggests its role in inducing metabolic and antioxidant beneficial effects. Furthermore, NIR light may also boost cerebral blood flow and cognitive functions in humans without adverse effects. In this review, we highlight the value of NIR therapy as a novel paradigm for treatment of visual and neurological conditions, and provide scientific evidence to support the use of NIR therapy with emphasis on molecular and cellular mechanisms in eye diseases." [1]

NIR = near infrared light, 670 nm wavelength. This wavelength is present in sunlight, but not found in basically any indoor lighting with the possible exception of full spectrum LEDs and IR bulbs. Another study found improvement from NIR exposure, but only from exposure in the morning (for three minutes, once a week, at 670nm wavelength), and only in individuals older than 38. The study proposes that the effects they found from NIR exposure is due to improved mitochondrial function in the retina. [2]

The human retina ages faster than other organs, with a 70% decline in functional ATP production by mitochondria over a lifetime. The aging mitochondria, in addition to not producing as much ATP, also spit out junk amino acids that can cause chronic inflammation in the area (and signal cell death where none is called for?). As an aside, improved mitochondrial function is also proposed to be responsible for the significant health benefits of fasting and prolonged calorie restriction.

Another study also theorizes this mechanism:

"Our data suggest, 670 nm light can significantly improve aged retinal function, perhaps by providing additional adenosine triphosphate production for photoreceptor ion pumps or reduced aged inflammation." [3]

More study is clearly called for the better understand what is going on here and why. It seems like it could potentially have implications for age-related degeneration throughout the entire body, not just in the retina.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7738953/\\ [2] https://academic.oup.com/biomedgerontology/article/75/9/e49/... [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5364001/

They have so many different recommendations they could do a "bullshit recommendation of the day".

Tell you to do something every day for the rest of your life. If it does not work, scold you for slacking off. If your vision does not degrade, praise it all on the topical bullshit therapy.

Why use so many words when few do the trick.

NIR has been known to be useful for a while. Closer to 1000nm, penetrates deeper, but isn't as 'potent'

670nm is great, but you can notice it when it's on, ESPECIALLY if it's the only light in your room, which can be annoying.

It's true that NIR stuff is healthy for your eyes, but HOW much so, is up to debate.

I've bought 10 30 W NIR bulbs to no effect (range from 650nm-950nm), but on the other hand blue light bulbs have been helpful with increasing visual accuity (shorter wavelengths appear to your eyes as fuzzy, so your eyes push themselves to refocus more often, though at the downside of low dopamine levels and no will to do anything {maybe this goes away with time? But I've spent a few days doing nothing due to blue light and I like to be productive}, while red light has no effect on motivation, but worsens my eyesight (light appears in focus, no need to refocus, eyes get "lazy")

All of this anecdotal, but I really do like reading/learning about this stuff and NIR seems to be more fad than not in real world situations

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