As one meta-analysis put it:
It’s estimated that an increase of one hour per day of outdoor time could reduce the occurrence of myopia in children by 45%.
Make sure your kids spend time outside, folks!
I spent 90% of my early childhood outdoors. Didn’t work.
I was outside a lot and still got myopia :3
Congrats on the luck
Then you were likely genetically predetermined to be at least a little myopic, but if you spent less time outside during your developmental phases you would likely be even more nearsighted than you are now.
N=1
deleted by creator
Near-sightedness
but my electronic image generator makes bam bam noise, must spend more money for more RAM
Hold up now. I grew up in the 80s when we spent the whole day outside, and I wore thick ass lenses all through grade school.
“Reduces chances” does not mean “prevents”
irrelevant because the term used here was “odds”, not chances
smfh
Uh OK same reply
damn people on Lemmy don’t like sarcasm huh
Oh good one
You should have “spend” the day outdoors not “spent”.
No. Spent is the past tense of spend.
They edited the title.
Ohhh, I see. I thought you were just a really bad grammar Nazi.
How do some people despite being wrong are happy to correct others? And they have up votes? Wtf…
My comment only makes sense with the original misspelled title of the post.
I see, my apologies then
We spent so much time outside we developed near sightedness instead
If you get this type of short sight vision, you can train your eyes to get the vision back as this is caused by the eyes strength.
But if you have the type that has to do with your eye shape going outside will do nothing, and you can exercise it away
You need to read better. It says it reduces occurrence of myopia in a population not that it cures myopia when an individual gets it.
Sure if you have very mild short term myopia caused by eye straining you can get vision back by training your eye. But with kids it’s about how the eye develops when it’s still growing. When kids eyes grow too fast they grow less spherical and that is what causes myopia and that is the kind that you can never cure. Going outside means kids are getting more sunlight in their eye which will slow down the growth and thus their eyes will grow more spherical which means they don’t develop myopia. Playing outside won’t cure myopia but it will reduce the chance of developing it in children.
Yes, I spent 6 months in ICU in 2014, I had a lot of eye issues while I was there not related to my reason for my stay (bilateral lung transplant) but as side effects of procedures and meds but I also basically lost my depth perception unless it was directly in front of me. Living in a 10x10 room for half a year with no far away distances to observe made my eyes weak, it took about six months after I got home to get my full depth prescription back. Indoors just makes your eyes weak, mine is an extreme example, but it doesn’t permanently ruin them.
Yes exactly. But for people with near vision from eye shape there is nothing you can do exercise wise to restore vision.
One hour of outdoor time per day is not a modest increase
I was outside a ton when I was younger and I still have myopia. These things happen.
You might have had a higher degree of myopia if you hadn’t spent all that time outdoors.
True, but I am like -2 or -3 in both eyes, so my myopia isn’t great either lol
Not great, but it’s also not -12 😀
Is this really causation though? Could it not just be that kids that spend less time looking at screens are less likely to be short-sighted AND more likely to spend time outside?
If this is just a correlation this would have to be a correlation at the population level. Countries where kids start school later on (e.g. 7 years old) have significantly lower rates of myopia than countries that start school early on in a child’s development (e.g. 3 years old). It’s still possible that this is a correlation, but the correlation would have to be capturing something deeper than just an individual kids screen time. Granted, this correlation would still need to account for differences between individual kids, but it would also need to account for differences between kids at a population level. It’s hard to see what could be causing this correlation though. So maybe there’s something there we’re just not seeing, but at a certain point though the idea that there is a causal relationship starts to seem like the most plausible explanation for explaining this data
It wasn’t mentioned in this article, but I remember reading somewhere that it might be because exposure to sunlight affects vitamin D production, which affects the length/shape of our eyeballs as we’re growing up.
Another idea is that when you’re outside, you spend more time focusing on objects further away, which helps develop those eye muscles
I’ve seen that too, with some emphasis put on viewing the horizon… though where I grew up it’s very unlikely to see anything close to horizon-distance without being at a beach (mostly because trees… better than indoors sure but not much non-treetop distance to look at unless you’re looking across a field/farmland, or maybe a radio/water tower or something).
though where I grew up it’s very unlikely to see anything close to horizon-distance without being at a beach
It would be interesting to see if people who live im these sorts of areas have higher rates of myopia. I’m not aware of any data that’s been collected on this though
A third idea is that sunlight is much, much brighter than most indoor artificial light, and the lack of this very bright light causes some sort of problem for the developing eye. Maybe the brightness of the sun is a sort of “calibration” method for the eye and when it doesn’t get that really bright sunlight, the development of the eye goes out of whack.
So is it vitamin D, or far-away views or bright sunlight? I’ve heard all these theories before but I’m not sure which is it. Does the meta analysis say anything about which effect is most likely the cause? I mean could we “fix” this by going outside to view things far away, or should we just take vitamin D supplements, or should we have much brighter indoor lighting? I’d love to know.
A third idea is that sunlight is much, much brighter than most indoor artificial light
Would this mean it’s a bad idea to give kids sunglasses?
Does the meta analysis say anything about which effect is most likely the cause?
Not that I saw though I admit I didn’t read the whole thing
Would this mean it’s a bad idea to give kids sunglasses?
Well if that is actually the causing effect, yes. I checked the paper and they do actually mention light brightness as a potential cause, as well as the other things but they have nothing on what actually causes the problem for real.
But I mean, clearly we aren’t naturally meant to need sunglasses so in a way I’d say yea, don’t give your kids sunglasses.
There have been RCTs conducted for this. For example
Myopia Prevention and Outdoor Light Intensity in a School-Based Cluster Randomized Trial
Pei-Chang Wu et al. Ophthalmology. 2018 Aug.
In this study, schools were selected and promoted either outdoor or indoor recess
well, i can concur. my eyes have trouble adjusting to looking into the distance when i have spent hours in front of the screen. they adapt after a few minutes to hours though.
I’m pretty sure short-sightedness is more a result of patience and critical thinking, but outdoors might help near-sightedness.
Sometimes I wonder if people see numbers like 45% and think “OMG, 45% chance!” instead of “small number * 1.45 = another small number.”
Considering that a fairly large percentage of children develop myopia (as high as 80-90% in some countries) a 45% reduction would be fairly significant, no? Or am I missing something
where are you getting these numbers… from what I can see, the global average was 23% in 2000 and 34% today.
The 80-90% claim seems to be repeated in various areas on the internet, including by the American Academy of Ophthalmology, which I assume to be reputable:
Over recent decades, the prevalence of myopia has skyrocketed, particularly in Asia. In countries like China, Japan, Singapore, South Korea, and Japan, up to 80-90% of teenagers and young adults are now myopic.
Of course these local averages are still consistent with a lower global average
I’m farsighted, so I can only conclude that I spent too much time outdoors as a kid. See Mom!?
“Also, while various theories such as increased light exposure, release of dopamine from retina, increased depth of field have been suggested to explain the protective effect of outdoor time, the mechanism remains to be elucidated”
Correlation is not causation.
You can establish causation even if you don’t know what the mechanism is. I don’t know to what extent causation has been established here though, I’m not familiar enough with the research. But at minimum the intuitive idea that there is a noncausative correlation because kids with bad eyesight choose to stay inside more does not seem to stand, since this phenomenon can exist at a population level (so countries where schools start younger - and kids go outside less - have significantly higher rates of myopia).
I don’t know to what extent causation has been established here though
I am familiar with the research. We don’t know the reason for nearsightedness. There is no known proven causation. It is likely there are different causes for it.
Being from a sunny country lowers the chance of it (so you’re less likely to be nearsighted if you’re from Spain compared to Norway), even when controlled for hours spent outdoors.
There are studies that just look at outdoor time. I don’t think we know the specific mechanism but we know enough to have recommendations.
Being from a sunny country lowers the chance of it (so you’re less likely to be nearsighted if you’re from Spain compared to Norway), even when controlled for hours spent outdoors.
This is very interesting
That depends entirely on how the correlation is determined. For example randomized control trials can establish causal inference.
