Comment by akemichan | Hacker News Reader

Comment by akemichan | Hacker News Reader

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There's a common misconception that using computers is the cause of hyper/myopia. The truth is that during the early years of development(up until 15-21 years old), the eye is not yet fully developed and it has great adaptability. This means that, if you are a kid and you read too much(on paper or computers or smartphones), the eye will develop to focus mainly on short distances, this developing myopia. This is the reason why kids textbooks have big letters, so that kids don't have to focus so much to read the text, and why kids using computers/reading too much(specially smartphone usage) is detrimental to their visual health. If you did this on your early ages, that certainly explains your issue, but it's not computers per se that cause it.

The other big factor is the shape of the ocular globe. Some globes are "longer" than others, which causes the image focused by the cornea and retina to land in front or behind of the retina, causing the hyper/myopia.

What you do actually experience a lot when using the computer too much is that when you focus on a task for a long time, your blink rate decreases, the tear film breaks more often, and you get sore eyes/eye fatigue. This is solved by regular breaks, or the 20/20/20 rule[0].

[0] https://www.aoa.org/AOA/Images/Patients/Eye%20Conditions/20-...

That 20/20/20 rule, assuming that the exact times are not critical, would fit in well for people using the Pomodoro Technique [1] for time management or something similar.

I find it interesting that it also fits will with ergonomic recommendations. Both sitting too long while doing computer work and standing too long are bad for you. See this article from the old Cornell ergonomics group site [2] for details on the perils of both. Their recommendation:

> Sit to do computer work. Sit using a height-adjustable, downward titling keyboard tray for the best work posture, then every 20 minutes stand for 8 minutes AND MOVE for 2 minutes. The absolute time isn’t critical but about every 20-30 minutes take a posture break and stand and move for a couple of minutes. Simply standing is insufficient. Movement is important to get blood circulation through the muscles. And movement is FREE! Research shows that you don’t need to do vigorous exercise (e.g. jumping jacks) to get the benefits, just walking around is sufficient. So build in a pattern of creating greater movement variety in the workplace (e.g. walk to a printer, water fountain, stand for a meeting, take the stairs, walk around the floor, park a bit further away from the building each day).

Do something like pomodoro for time management and during the breaks between pomodoros spend a couple minutes walking around and looking at things in the distance and you've covered protecting both body health and eye health from the risks of computer work.

[1] https://en.wikipedia.org/wiki/Pomodoro_Technique

[2] https://ergo.human.cornell.edu/CUESitStand.html

I found having the brightness of the monitors turned helps alot, my monitor lux level is like 30 from 5cm away from the monitor. Plus as a kid I had glasses because the TV made my eyes water, the new LED light bulbs do the same thing as do some TV's.

Now a variety of chemicals are involved in eyesight, histidine has been shown to reduce or prevent cataracts building up in Salmon, vit K alters an enzyme which also reduces the calcium buildup in the eye, so I wonder if eyesight is purely down to diet and exercise?

As far as I know, there's not much evidence that physical exercise can influence visual acuity on humans(other than reducing it due to general body fatigue), though I'd love to read more on that if someone happens to know of a study on the subject. Diet, on the other hand, may influence it. Generally speaking you can't consider a part of the body as if it were it's own isolated system: the general state of the body will influence them. To give a practical example, contraceptive pills change the tear composition making it hard for women taking them to use contact lenses.

Most of the issues related to lights/monitors, apart from the effects on the eye development due to prolonged near distance focus, are related to the quality of the tear film, not so much about the actual visual acuity or the refractive capacity of the eye. For example, the ambar-colored night mode that most OS have now not only decreases the brightness, which helps with visual fatigue, but also stimulates the production of melatonin, which is essential to enter "night mode" and make it easier to fall asleep, in contrast with blue lights, which reduces melatonin production and puts you on alert mode during the day.

In humans, cataract is mostly(not accounting for birth pathologies or trauma) caused because the crystalline, since we are born, never stops producing collagen, the substance it's mostly composed of. At late ages, the crystalline has produced so much collagen that it loses transparency, thus causing cataracts. It's also the same reason people develop presbyopia as they age: the collagen production reduces the crystalline elasticity, making it harder and harder for the eye to adjust it and focus on near distances.

K1 Enzyme I think I was thinking about. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6789135/

Salmon cataracts https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2709424/

>you can't consider a part of the body as if it were it's own isolated system True, we cant control where some chemicals go in the body, but this is where the pathways come into play or the other chemicals in a meal. For example, there is reportedly a gut receptor for copper or zinc which can take upto about 800mg a day, but copper and zinc are competing obviously. Other factors include say tea drinking, wear https://www.sciencedirect.com/topics/food-science/phytate inhibit copper, zinc and iron iirc.

So when thinking about say supplementing, sometimes the delivery mechanism or consumption format doesnt help.

Vitamin K1 doesnt appear to have an upper limit if taken orally, but inject it and you will get a reaction.

Its like a complex chemical maths puzzle, but by bit studies give us a range of info and its a case of piecing it all together. In some cases studies dont even exist!

Well that definitely tracks my theory. As outlined https://news.ycombinator.com/item?id=30412185 I definitely didn't develop the short distance focus habits as a child.

Do you know if the childhood developmental component has any relation to above average vision?

> Do you know if the childhood developmental component has any relation to above average vision?

Unfortunately I don't know, I'd like to know more too :)

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