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-...
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.
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?
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.
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!
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 :)
See, this is the problem with validating with anecdotes. For one for, five can be immediately found against.
Theres clearly "developmental" and "inherent", eye issues. My partner has a thorny case of astigmatism, you don't just develop a structural defect in the eye like that from environmental inputs, so its an established situation that some percentage of human eyeballs turn out different, it would be naive to think at least some percentage of long and short sightedness didn't also occur in this way.
But once again I'm a computer person not a medical researcher so I could be wrong and it might be well established fact that astigmatism is the only inherent defect you're born with.
Unfortunately I’m in computers not medical research or I’d have considered proposing a study, but I look forward to the day someone else diligently studies it and I get an answer to my personal pet theory.