Hacker News Reader

Comment by ipnon | Hacker News Reader

"If children get outside enough, it doesn't matter how much they study they do. They don't become myopic," said Ian Morgan, researcher at Australian National University.[0]

"Researchers say kids and teens need to get sunlight during the critical years of their development while their eyeballs are still growing.

"The mechanics of how sunlight protects their eyes are not clearly understood. One theory suggests that sunlight triggers the release of dopamine in the retina; another speculates that blue light from the sun protects from the condition.

"The solution is simple. Have kids "spend more time outside, have less demands (from) the schools and relax a bit," said Seang Mei Saw, professor of epidemiology at the National University of Singapore."

[0] https://www.cnn.com/2015/04/05/asia/myopia-east-asia/index.h...

edit: quotation marks

View on HN

Meanwhile we put 5-6 year olds in kindergarten classrooms with UV-blocking windows all day, for about 9 months during the part of the year with the least sunlight available, and we've cut recess time down to almost nothing, and schools increasingly don't send kids outside if the weather's anything other than perfect. At my kids' school they don't even have indoor recess if they keep them in! They just watch a damn movie. WTF. Of course there was some stupid educational fad that led them to remove all the toys from lower-grade classrooms to make room for "learning centers" (I gather this has happened more or less state-wide), so I guess if the gym's not available they can't really do indoor recess anyway, not that it helps their eyesight either way. And this is a very highly-ranked school for our state.

1.5 hours of recess daily minimum or bust for 3rd grade and under, I say, and I think that's not quite enough, really. Screw this 30 minutes crap. Know how I can guarantee my kids have behavior problems at home? Coop them up inside all day. Know how I make a day run smoothly? Make sure they're outside running around at least a couple hours while the sun's up. Then consider that they're giving a bunch of them nearsightedness on top of definitely creating behavioral and learning problems. It's crazy.

I think it's all a side effect of the treadmill that society is putting everyone on. Between globalization and automation there are fewer good jobs that more people are competing for. Either you end up with what used to be a lot of money or way too little. Till you "made it" you are constantly at risk at slipping off the treadmill and into the "way too little" group. Especially in the US.

May this be reality or not, it's the experienced reality for many. We feel so much pressure to give our kids a head start which results in this rat race starting earlier and harder. I think this is just collateral damage from that shit going wrong. I'm so glad I was a kid in the 80s when playing outside was still normal.

We let ours play outside plenty, and there are quite a few other kids out. Does seem to be neighborhood-dependent, though, all kinda have their own culture. Our current one's less free-range than the last, which had big ol' gangs of kids with large age-ranges roaming around, and was great.

We are fairly worried about 1) eventually having some kind of encounter with child protective services—which will likely end up fine, if it happens, but will also probably be really inconvenient and stressful—and 2) injuries that end up giving us yet another opportunity to play everyone's favorite game, Medical Billing Roulette, especially now that they're riding bikes. Multiple kids, just a matter of time until one of them get a hospital trip out of a bad fall. Odds very low they'll all make it to 18 without at least one broken bone.

God damn do I wish we'd fix healthcare in the US. It's crazy how much background stress & anxiety that causes across just about all activities and choices. And that's with insurance.

[EDIT] although I'm pretty sure the "playing outside" thing tapers off around tween/teen ages in a way it didn't for us, when they all start living on social media. :-/

> Odds very low they'll all make it to 18 without at least one broken bone.

I consider broken bones to be an integral part of childhood. Well, for boys anyway.

If you make it to 18 without a broken bone, you probably should have spent more time outside.

I haven’t broken any bones. My parents were up and coming immigrants with their own business, but not successful enough to afford health insurance (pre ACA, but not post ACA either), and there weren’t poor enough for Medicaid.

So my dad was clear to me that any injuries could cause us to have medical expenses that would derail us and my younger sibling’s future as well as the aging grandparents my parents were taking care of.

So I didn’t partake in activities that could have broken bones, but that is the hand my parents and I and others like us are dealt in the great old US of A.

And don't you think that's a horrible situation to be in?

It's completely foreign to me that there exists a first-world country where you need to bar your child from certain activities solely due to concerns over potential medical costs.

That's not a criticism of your parents - their decision was completely logical in the circumstances. It's just a fundamental flaw in the US system.

Of course it’s a bad situation. Just explaining why some kids may not have had broken bones.

If you’re not in the upper class or extremely poor class in the US, there is no safety net, so if you want any chance of clawing your way up to having the various securities of life, you have to play it safe.

I’m sure you’re making a general statement, but breaking a bone is pretty traumatic and the complications can be quite serious. I hope my kids never experience a broken bone.

That said, I spent my childhood outside and never broke a bone myself, but my brother did and ended up having to wear orthotics the rest of his life and routinely experiences discomfort as a result. So, my advice, don’t limit your kids, but teach them to be careful at the same time.

I’m pretty sure if one of my kids break a bone, I’m going to be a wreck.

EDIT: Your comment about boys breaking bones more than girls is ridiculous, as a parent with a daughter who loves risk taking, I can assure you it’s not a boy vs girl problem.

> EDIT: Your comment about boys breaking bones more than girls is ridiculous, as a parent with a daughter who loves risk taking, I can assure you it’s not a boy vs girl problem.

"The lifetime risk of sustaining a fracture in childhood is approximately 42%-64% in boys and 27%-40% in girls, with remarkable variation in the estimates worldwide [1-4]. While fractures more often occur in males, girls usually sustain fractures at a younger age compared to boys"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2987399/

No broken bones here before 18, I grew up on a farm, had access to many machines (bikes, quads, tractors, cars, go karts). Spent huge amounts of time outside and liked to try more and more dangerous things partly due to be somewhat isolated, some of which would have done more than just broken a bone.

There's always exceptions to every rule. That's why I said "probably".

I like the sentiment, but there's several factors here, including inherent "agility" and of course luck.

I never broke a bone as a kid, and not only spent half my youth outdoors but was a daredevil.

Summer: Tree climbing, as high as 50'. Constant bike riding on and off road, skateboarding, go carts, dirt-bikes (hill climbs, jumps), jungle gym, stilts, pogo sticks, trampolines, swings, water-skiing, touch football, street hockey, basketball, and soccer.

Winter: Flexible flyer sledding on steep hills with frequent collisions and wipe-outs (that was half the fun), snowmobiles, tubing, skiing, skitching (when streets are snowy/icy you hold on to a car's bumper and hitch a ride)

One of my own kids has the daredevil streak also and built huge jumps for bikes in summer and snowboards in winter. They'd jump over cars.

No broken bones (lacerations, bruises, sprains however)

On the other hand, I saw a kid break his leg at 2 mph by falling off his bike against a curb.

I guess but I feel like the schooling they get is largely bogus anyhow especially in elementary school and nothing I couldn't fix by just tutoring them a bit at home

> Then consider that they're giving a bunch of them nearsightedness on top of

If it's any consolation, the drawbacks of myopia are fairly negligible. This is one reason there's not a lot of effort expended to prevent it.

I actually enjoy it. I’m at a point where I could get laser correction, but I’ve found that I value being able to remove my glasses and quite literally de-focus too much.

I also dont like how people put sunscreen on the kids almost every time they go out. I live in Australia, so you absolutely do want to protect your skin, but heading to the park for an hour doesn't need sunscreen every time.

2 generations ago it was common to literally lie in the sun for hours putting coconut oil on your skin to increase tanning. And yes they did have higher skin cancer rates but there is a fair gap between that and not doing it + a long sleeve shirt/hat.

Im trying to move to a screen free Sunday to encourage more outdoors/interaction but screens are so ingrained in our lives now its not popular.

I'm not sure what to think about that. I live in CO and people here that don't sunscreen are so much more damaged than others I know in different states. It's drastically obvious. So I sunscreen my kids like crazy. I keep thinking that I'm at least giving their adult selves the option to look 50 at age 35 if they decide to quit using sunscreen religiously. Unsure if this is the best approach. Their doctor loves it though.

I'm in Australia and have an annual skin check. The doctor advises adults to use a moisturiser with sunscreen component as a daily default, especially anyone with fair hair. My wife tends to do this.

The doctor has mentioned in the past that 60+ year old males who've worked farms or building sites their entire lives have a 35%+ strike rate on finding a cancerous mole when they come in for a check.

> I also dont like how people put sunscreen on the kids almost every time they go out. I live in Australia, so you absolutely do want to protect your skin, but heading to the park for an hour doesn't need sunscreen every time.

I'm making an effort to get at least 15 minutes of direct sunlight every day, but at the same time, I make sure to put sunscreen on my face/neck every time I go out.

Modern attire is the problem. Our clothes cover everything but the face, hands and neck, so when we try and increase sunlight exposure, we get huge doses concentrated on these areas.

Ideally, I'd be sunning shirtless and with shorts that cover as little as legally possible. It's a much more sensible approach to boosting Vitamin D levels without risking skin cancer on the face/hands/neck/ears. Nebulous concepts of "social acceptability" be damned.

> And yes they did have higher skin cancer rates

Much, much higher. And older people who were reasonably active and spent a lot of time outside (even if they didn't deliberately go and sunbathe) have often had one or two cancerous spots cut out.

I'm sure there is a correlation, maybe even a strong one, but I have quite a bit of anecdata to suggest it is not true in all cases.

(I grew up on a farm, and spent a helluva lot of time outside, and needed glasses long before my family had a computer; my father would have spent even more time outside than I did, and likewise is pretty nearsighted.)

Had the inverse situation observed too. One of my friends has been writing code intensely since at least the age of 11, still spending tons of time in front of the screen. Never needed glasses in his entire life. And then there is me, who had very limited access to screen time as a kid, and I still ended up needing glasses around the age of 15 (despite none of my parents needing glasses, which goes to show that "genetic" doesn't necessarily mean something as simple as "your parents are this way, so you are bound to be the same way").

I am not a doctor, but imo it is similar to a lot of other health concerns. Predominantly genetic, but you can still affect the outcome in slight ways and improve your chances a bit.

Personal example: my grandfather who has been smoking at least a pack a day since the age of 9, and he is still doing way better in his 80s than majority of people his age. Working in the garden (even physically demanding stuff, like preparing the soil for potatoes every summer), fully mentally sound, etc. On another hand, you have plenty of young people who do everything right (no smoking, healthy diet, regular proper exercise, etc.) falling due to random health ailments. Which goes to show that while taking care of yourself is important and beneficial, the luck of hand you got can override it all in either direction at any moment.

The link references the rate of myopia in South Korea increasing from 18% in 1955 to 96% in 2011. This suggests 2 things:

1. Myopia is not entirely genetic, because genes for myopia could not have spread to almost all Koreans from almost no Koreans in the span of 56 years.

2. Myopia is somewhat genetic, because myopia existed in a significant proportion of the pre-industrial population.

Prefixing this with an acknowledgement that I totally believe there was a change in the prevalence of myopia due to changes in environmental conditions (amount of sunlight, artificial lighting, etc etc)...

I am curious whether 18% was the diagnosed rate of myopia in South Korea in 1955 or the actual rate of myopia in 1955.

In 1955 South Korea was a poor country; now it is one of the wealthier countries (per capita) in the world. On the one hand, it is entirely believable to me that access to eye correction is radically greater than ~70 years ago, and there was a lot of undiagnosed vision problems in 1955. On the other hand, it's also entirely believable to me that literally every 20 year old (male) was given a vision test in 1955 in South Korea, because of the War. On the third hand, it's also entirely believable to me that the vision test given was fairly easy to "pass", and that a many of the people who passed it would have a level of myopia that we would now prescribe glasses for, because hey, better vision is better.

> Myopia is somewhat genetic

That conclusion is can't be supported from the above fact alone.

It could be a development disorder with a certain probability of occurrence given other non-genetic factors.

Perhaps some pre-industrial people didn't get enough sun time, because they spent too time at home reading. Others had physical eye damage from work activities, etc.

I have always been under the impression that myopia was caused by growing too fast as a child, leading to misformed eye balls. Basically children with too much food get myopia. Surely that fits the same data pretty darn well... I wish I had a study to point to but I heard/read this decades ago.

I agree. This is the first time I’ve heard of it. Literally everyone in my family wears glasses, including my deceased grandfather who lived into his 90s. He grew up in rural Mexico without electricity so it absolutely couldn’t have been caused by TV or Computers

What did you spend your time doing though? Did you read a lot? Did you draw? Did you spend a lot of time working on things within arms reach? Or did you spend your time staring off into the far yonder? Isn't there a case to be made that sunlight is more of a signal used to help the eyes learn to focus and that by staring at something a foot away with low signal strength the eyes never got the feedback necessary to shape itself to the environment that it needs to work in?

Climbing trees, chasing livestock, running through fields, catching frogs, rolling down hills, digging holes... ?

I was outside. If what a small child running around on a farm for hours and hours every day, rain or shine, doesn't count as "being outside more", we need to start using a different word to refer to that.

I got another weird one to toss in, for myself:

Back when I first moved into my current place in 2013, I was able to read my stove's clock from across two rooms. My eyesight had steadily degraded since then until last year/early this year, where I needed to step into the closer room before I was able to read it.

...But then, the lockdown started. And since then, despite being on the computer for more of the day and not often going out into the sunlight, my eyesight has been improving. I can clearly read the clock from across both rooms again.

Since I don't really open my blinds, I've gotten pretty much continuous indoor levels of light for two months now, so I've my own theory: It's not specifically sunlight, but having to adjust to the differing brightness between indoor and outdoor light too often that causes issues.

Does anyone know if this also applies for people in their early 20s? Of course more sunlight and exercise never hurts, but I’d be more compelled if there’s scientific evidence that it stops myopia progression.

Yes[1].

[1] https://www.nature.com/articles/s41598-017-09388-7

Anecdotally I had great vision (20/15) before starting college. Before I went to college the eye doctor said not to bother coming back until I got married. After 3 years of looking at a screen in the dark I needed glasses.

You know that movie, Moon, with Sam Rockwell? I started feeling like the first version of the clone right after finishing university. I just keep falling apart!

Nah, just Flux in more blue light during the day. /s

Isn't near-sightedness an adaptation? Nearsighted people can see closer things better. For example, I don't have clinical eye problems but I have some friends who are severely near-sighted, and they can read the security text on US money whereas I cannot.

Is there higher incidence of myopia in places with less sunlight?

Reminder that being outdoors and sunlight have nothing to do with myopia. It's about how much light is focusing on your fovea and in peripheral vision. Being outside is just one common way that your peripheral vision isn't constantly in focus because there's not a screen filling up most of your periperal vision.

Your statement does not make clear whether you're making a positive assertion about the mechanism of myopia, or whether you're making an assertion about some other potential eye condition.

If you are making a positive assertion about the mechanism about myopia, then you are directly contradicting the article, which states the mechanism is not clear. While it may be the case that the article is misrepresenting the science, I personally find this to be unlikely.

In which case, given you are asserting an alternate hypothesis compared to the null hypothesis presented in the article, I do ask you for some more backup to your claims.

I urge you take this seriously. It's frustrating that more people don't understand this topic, but I can't blame you for your ignorance, because you probably only learn from articles like these. Google for myopia control and start learning.

I'm looking at it entirely from an academic point of view. I personally have hyperopia, so a bit of added myopia might actually help. As distinct from presbyopia, which is different again.

Reply on news.ycombinator.com