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Sajusa
12-05-2019, 06:46 PM
Why do so many people have myopia since childhood?

FionnSneachta
12-11-2019, 11:13 PM
In my case, according to Promethease, I have an increased risk for myopia at rs12803066 with a magnitude of 2.5. I did develop myopia in childhood. I can't remember my exact age but I was about 9.

slievenamon
12-12-2019, 05:15 AM
I was about seven or eight years old, when the myopia was corrected with glasses.
There was also a diagnosis of astigmatism in one eye.
No one else in the family was nearsighted.

FionnSneachta
12-12-2019, 07:13 PM
My mum wears varifocal glasses so needs them for reading and seeing in the distance. My dad has reading glasses but he only got them when he was in his 50s, I think. My brother doesn't need glasses so he'll probably be like Dad and just need them for reading when he gets older.

lgmayka
12-13-2019, 02:27 AM
In my family, this is clearly a 20th-century phenomenon. My father had very mild myopia, my mother none. But all five of their children developed rather severe myopia, at ages 11-16. I would look for environmental/developmental factors such as:

- Night lights for toddlers (https://www.nature.com/articles/20094).
"We have looked at the effects of light exposure on vision, and find a strong association between myopia and night-time ambient light exposure during sleep in children before they reach two years of age."

- Lack of outdoor time (https://www.reuters.com/article/us-health-children-myopia-outdoors-idUSKBN19W29Y).
"Kids who spend more time outdoors and who play sports are less likely to be near-sighted, according to a recent study in a large, diverse group of urban 6-year-olds."

- Exposure to excessive red-shifted light (https://iovs.arvojournals.org/article.aspx?articleid=2127682) (e.g., the yellow light produced by a typical incandescent bulb).
"Rearing chicks in red light caused progressive myopia, while rearing in blue light caused progressive hyperopia."

firemonkey
12-13-2019, 09:09 AM
I was nearly 14 when I had my first eye test. At 14 I had glasses .

lgmayka
12-13-2019, 03:24 PM
Exposure to excessive red-shifted light (https://iovs.arvojournals.org/article.aspx?articleid=2127682) (e.g., the yellow light produced by a typical incandescent bulb).
"Rearing chicks in red light caused progressive myopia, while rearing in blue light caused progressive hyperopia."
In 2002 I underwent Lasik surgery to correct my myopia. After a few years, I noticed that it was returning! Not terribly, but enough so that I had to buy eyeglasses for night driving.

But around the same time, I replaced all the light bulbs in my house with "daylight" bulbs (5000K-6500K color temperature)--simply because I prefer white light to yellow light. After several years, I noticed that my myopia was gone--I could drive at night without eyeglasses again! (Of course, this also means that I now use reading glasses more often.)

So perhaps human eyes are not all that different from those of baby chicks?

Milkyway
12-15-2019, 10:20 PM
I'm the odd one in the family. Aside from me, nobody but a 1st cousin wears glasses (I've got astigmatism + myopia, and I'm almost blind at night). I had glasses for the first time at 9, after the teacher realized I couldn't read the writing on the blackboard. I think that there must be environmental factors involved as well since roughly 50% of the population has myopia in certain Asian countries, and the prevalence is higher than ever.

I've heard some theories that link myopia to IQ (it seems that the more intelligent children tend to spend more time reading books indoors, which may damage their eyesight).

I didn't do anything different from other children of the same age, so I don't know why I developed myopia when others didn't.

glentane
12-16-2019, 12:56 AM
I suspect it's a modern ailment. Caused by modernism.
Until the industrial revolution and the emergence of precise small-scale measurements (in time, dimension, threads on a loom, or a rifle-screw, any physical quality you care to mention) it didn't really matter, as long as you could [a] see to the end of a furlong (the wicket sticks) or at least as far as the lead ox's nose, and hold a bow in the front row and not shoot your neighbour accidentally. The French are over there, daft lad! Somewhere ..

Literacy was an unheard-of affliction, and coincidentally clerics are often shown holding some sort of eyeglass, which therefore became a high-status signifier of wisdom or "intelligence".

Like "hyperactivity" or "seasonal affective disorder". Inflicted, out-of-area disorders.

I mean, before Mr Murdoch caught on to that old colliers' stunt of heating parrot coal in a kettle, sticking a musket-barrel on the spout and touching fire to the evolved "fumes", what the heck else was anyone going to do between November and February? No lights indoors or out, just the fire, maybe a candle in a horn box for the Farmer, which the wind would make short work of.
Barely time to get the beasts yoked up, or the yowes milked when they were in-bye. Used to be piecework weavers would have a single candle, magnified by a water-filled glass flask, to quickly go blind by in the back end of the year.
It's extraordinarily wet, cold and [B]dark in Britain in the winter. Solid low cloud cover, and no snow. Usually violently windy and raining too.

tl;dr people have ailments these days simply because they are diagnosed.
e.g asthma was unknown when I was at school. Those kids were simply "lazy"(thwack!) in sports, or "stupid"(thwack! thwack!!) if they were dyslexic, or myopic, or slightly deaf.

Come to think of it, The Past is always pretty horrible.

Ramiro
12-17-2019, 02:44 AM
As far as I know, myopia is transmitted to children from parents, this is a genetic disease. I also know that many children play a lot on tablets, watch TV a lot and don't follow simple rules that help reduce the negative impact on their eyes. My son loves to read before bedtime and I always remind him that he need to use the right lighting for this (on this portal bestlightguide (https://bestlightguide.com/best-book-lights-for-reading-in-bed/) you can learn more about which lighting is best for reading, what lighting is best for the bedroom so that there is no sleep disturbance), that you need to keep the book 30 cm from the face and that you shouldn't read on the side or top with brakes. This helps preserve my son’s vision.