As reported by TreeHugger
In the U.S. and Europe, myopia for kids and young adults has doubled; in China it’s up 80 percent. Scientists think they’ve found out why, and it’s probably not what you think.
For years the thinking was that myopia was largely genetic, but research began to show that it wasn’t purely a matter of genes. And indeed, the current increase in myopia reflects a similar increase in children reading and studying more. But surprisingly, it’s not the reading and computers and smartphones that are to blame. Now researchers believe that it’s the very act of spending too much time inside that is causing the problem.
After a great deal of research and eliminating other factors, scientists now think that it boils down to exposure to bright light. The leading hypothesis is that light stimulates the release of dopamine in the retina, and this neurotransmitter in turn blocks the elongation of the eye during development.
Based on epidemiological studies, Ian Morgan, a myopia researcher at the Australian National University in Canberra, recommends that children spend three hours per day under light levels of at least 10,000 lux for protection against the condition. Ten thousand lux would be about the amount of light one would get from beneath a shady tree on a bright summer day (and wearing sunglasses). For comparison, a well-lit schoolroom or office is generally under 500 lux.
(Score: 5, Insightful) by MichaelDavidCrawford on Saturday March 28 2015, @11:32AM
recall the recent controversy over the father that was threatened by child protective services because he encouraged his children to walk a mile home, from a park.
When I was that young, I used to walk a lot farther than that, all by myself. When I was three years old, my six year old sister would walk me to preschool, but when I was four I walked alone. I lived on a naval base, so it wasn't like I'd get kidnapped - just hit by a truck loaded with ordnance. :-D
I am completely convinced that the epidemic of childhood obesity is caused not by sugary drinks, junk food nor video games, not directly anyway, but by the fact that today's children do not play outside.
Yes I Have No Bananas. [gofundme.com]
(Score: 0) by Anonymous Coward on Saturday March 28 2015, @11:59AM
Outdoors is where the pedophiles are.
(Score: 4, Funny) by maxwell demon on Saturday March 28 2015, @12:05PM
Great, so we can start screening for pedophiles by testing vision. Anyone not near sighted must be a pedo! ;-)
The Tao of math: The numbers you can count are not the real numbers.
(Score: 1, Insightful) by Anonymous Coward on Saturday March 28 2015, @12:22PM
The indoors is boring with flooring, but the outdoors is where you can really feel the mud, sand, grass, and concrete beneath your feet.
(Score: 5, Funny) by c0lo on Saturday March 28 2015, @12:51PM
And germ, don't forget the germs. A great deal of profit will be lost if we stop being afraid of germs.
(I never got to understand that "kills 99.99% of germs" ads. Seems I'm not the only one [xkcd.org]).
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Funny) by bzipitidoo on Saturday March 28 2015, @01:18PM
Obviously we need to take more vitamins! A deficiency of vitamin A must play a role in nearsightedness. Just ask your doctor. And buy more cod liver oil.
(Score: 5, Informative) by NotSanguine on Saturday March 28 2015, @02:45PM
the outdoors is where you can really feel the mud, sand, grass, and concrete beneath your feet.
And germ, don't forget the germs. A great deal of profit will be lost if we stop being afraid of germs.
(I never got to understand that "kills 99.99% of germs" ads. Seems I'm not the only one [xkcd.org]).
Right. Got to get rid of those filthy nasty microbes. Seeing as most microbes that live in or on us (and there are ten times more of them than our own cells [scientificamerican.com]) are beneficial to us, the whole "eww, germs!" thing is pretty ridiculous and is a result of gullibility on the part of the masses, and fear-mongering on the part of marketers who want to sell us stuff.
Sigh.
No, no, you're not thinking; you're just being logical. --Niels Bohr
(Score: 0, Disagree) by Anonymous Coward on Saturday March 28 2015, @02:58PM
sex builds character
(Score: 5, Informative) by opinionated_science on Saturday March 28 2015, @01:43PM
"I am completely convinced that the epidemic of childhood obesity is caused not by sugary drinks, junk food nor video games, not directly anyway, but by the fact that today's children do not play outside."
The statement contains connected activities!! It is BOTH diet and lack of exercise that makes children obese. When the human body is active there is a great deal of metabolic activity that is involved, this permit the energy balance to be maintained.
In general the problem is that as we age, there is less general growing going on - hence we need fewer calories. But the muscle is what burns the energy and the general change in physical activity following education and entering full-time work(say post-college), leads to the general loss of fitness.
This biology has been clinically measured. Humans will continue to grow new muscle right up to the 90's (as far as we know!) in respone to exercise, The process slows down with age in conjunction with loss of testosterone (in men ,anyway), but doesnot change as fast as the population obseity would suggest.
In short, use it or lose it. But don't dismiss diet. HFCS is toxic with the quantities it has been used in the US food chain.
(Score: 3, Informative) by Magic Oddball on Saturday March 28 2015, @03:54PM
HFCS is toxic with the quantities it has been used in the US food chain.
To be more accurate, fructose is harmful if ingested in large quantities [sciencebasedmedicine.org], regardless of which sweetener it's produced by. (There's a nice avalanche of biochemical explanations on the web of why HFCS is indistinguishable from sucrose or other common sweeteners from the body's perspective, beyond that they are all comprised of glucose+fructose. I don't have time** to track better ones down, unfortunately.)
**I couldn't sleep last night, but I evidently can right now whether I want to or not. Bleh.
(Score: 2) by opinionated_science on Monday March 30 2015, @03:13AM
HFCS is sweeter than sucrose and also cheaper. It is chemically different due to the inhomegenous quantities of the molecular constituents, fructose and glucose.
Glucose is processed and can be processed by every cell in the body. Insulin is the hormone that regulates glucose, which is toxic in high concentrations.
Fructose has to be metabolised by the liver, leading to a substrate (transformation to aldehyde) and then processed in the identical manner to ethanol (also converted to an aldehyde by alcohol-dehydorgenase).
Therefore, over time the body gets to store the fructose as fat, but also invokes an incorrect amount of insulin. This "selects" for insulin production that is too low, and over time type 2 diabetes occurs - insulin resistance.
Type 2 diabetes is the only disease we know how to cure completely using diet and exercise. HFCS is not legal in Europe, as there is no corn lobby.
(Score: 5, Informative) by Snotnose on Saturday March 28 2015, @02:05PM
Agreed. I grew up in the 60's/early 70s and we spent a lot of time outside. We used to walk with our bb guns, pellet rifles, and bows and arrows a couple miles down busy streets (Lake Murray and Navajo) so we could climb Cowles mtn, then walk those same streets home. Nobody said a word. Rode my bike a few miles to the not-close-but-much-better library in La Mesa, not an eye was batted. Pretty much, if the sun was out so were we.
That said, I first got glasses at 11. I still remember how amazing it was to realize how everyone else could read the blackboard.
When the dust settled America realized it was saved by a porn star.
(Score: 3, Funny) by Anonymous Coward on Saturday March 28 2015, @11:47AM
I've already turned the brightness up to maximum and it's still not enough. I'm tired of the daylight causing glare on my screen while I'm trying to read my own witty comments. It's so much worse at midday too. Fix it for me, boffins, or eliminate the sun, I don't care which.
(Score: 1) by wisnoskij on Saturday March 28 2015, @01:52PM
I retreat indoors to get out of the bright blinding light. If bright light is damaging the development of our eyes, going outside is not going to help anyone.
(Score: 1, Disagree) by wisnoskij on Saturday March 28 2015, @01:54PM
Oh, never-mind, I was reversed.
Still, hanging out under a shady tree with sunglasses on is not even close to 20 times brighter than a classroom.
(Score: 2) by frojack on Saturday March 28 2015, @06:23PM
Yeah, the article kind of read like it was blaming bright light, rather than blaming the lack of bright light.
After a great deal of research and eliminating other factors, scientists now think that it boils down to exposure to bright light. The leading hypothesis is that light stimulates the release of dopamine in the retina, and this neurotransmitter in turn blocks the elongation of the eye during development.
TFA is short on specifics here. The elongation of the eyeball is pretty much the definition of Myopia [allaboutvision.com]
No, you are mistaken. I've always had this sig.
(Score: 2) by TheLink on Sunday March 29 2015, @08:23AM
When you look downwards without tilting your head a lot you can feel stretching of your eyeballs. Whereas most of us can look upwards without feeling significant stretching.
So more kids looking downwards to read books, devices etc = more stretching of eyeballs (esp while it is growing) = more nearsightedness. And that's why those "bookworms" are more likely to be shortsighted. Young children can't hold books far away from their eyes either - their arms are too short.
Slouching back and looking at the TV probably does stretch the eyeballs too due to the angle.
(Score: 0) by Anonymous Coward on Saturday March 28 2015, @02:55PM
https://justgetflux.com/ [justgetflux.com]
(Score: 0) by Anonymous Coward on Saturday March 28 2015, @02:56PM
People in their '50s and '60s can't do a lot of things as well as when they were younger.
Wait, what?
(Score: 0) by Anonymous Coward on Saturday March 28 2015, @03:06PM
I thought this was well accepted/established. Guys in jail that don't see much outside get their eye sights all screwed because their eyes rarely get to focus on objects far away.
(Score: 0) by Anonymous Coward on Saturday March 28 2015, @03:28PM
Staring at a computer or TV screen that slowly degrades your vision.
(Score: 5, Informative) by Gaaark on Saturday March 28 2015, @05:16PM
...maybe it boils down to 'when you are inside, most things are up close to you' vs. 'when you are outside, you spend a lot of time looking at things 'far away' which gives your eyes more 'practice' at far sightedness.' (such as when playing baseball and looking for that tiny ball high in the sunny sky as it comes straight for your head) and trying to figure out if that person with the familiar way of walking really IS your buddy down the street....
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 3, Informative) by frojack on Saturday March 28 2015, @06:27PM
The new theory suggests its not "practice", but rather caused by the elongation of the eyeball in childhood, a physical change, and this is something no amount of practice will fix.
No, you are mistaken. I've always had this sig.
(Score: 3, Funny) by kaszz on Saturday March 28 2015, @06:40PM
Did some calculus on that 10 000 lux. If you have a small room like 2 x 2 meters with a 2.5 meters height. The light source needs to output 240 000 lm. Using a 15 W LED light source at 1500 lm, one needs 160 of them. And 2400 W to power it. One light source for every 2.5 dm².
In other words. To fix it indoors, you will need some cash and power.
(Score: 2, Funny) by mr_mischief on Saturday March 28 2015, @07:04PM
Or a glass house. Just don't throw stones.
(Score: 3, Interesting) by gringer on Sunday March 29 2015, @04:39AM
Did some calculus on that 10 000 lux. If you have a small room like 2 x 2 meters with a 2.5 meters height
Lux is lumens per square metre, so a tiny 2x2 room needs 40,000 lumens, or "only" 27 of your 1500 lumen light sources, taking a little over 400W.
Ask me about Sequencing DNA in front of Linus Torvalds [youtube.com]
(Score: 2) by kaszz on Monday March 30 2015, @12:51AM
You missed the walls. I excluded the ceiling on the other hand because the beam direction will be down or the ceiling will be reflective.
(Score: 2) by gringer on Monday March 30 2015, @04:42PM
I'm not quite sure how the walls would increase the light requirement, unless they were painted matte black or something like that. Could you please explain your line of thinking a bit more?
Ask me about Sequencing DNA in front of Linus Torvalds [youtube.com]
(Score: 2) by kaszz on Monday March 30 2015, @10:10PM
Your eyes will in most cases have three walls and half the floor within the field of vision. So light reflected from walls and floor matters. Under the assumption every surface is painted white matte.
In dark climate zones, wrong sleep cycle or seasonal depression scenarios these kind of none sun tanning light may be useful. Perhaps high lux environments will make the skin produce vitamin D in significant doses?
(Score: 2) by gringer on Thursday April 02 2015, @05:51AM
Your eyes will in most cases have three walls and half the floor within the field of vision. So light reflected from walls and floor matters. Under the assumption every surface is painted white matte.
But wouldn't that increase, rather than decrease, the amount of light hitting your eyes?
Ask me about Sequencing DNA in front of Linus Torvalds [youtube.com]
(Score: 2) by kaszz on Thursday April 02 2015, @04:14PM
Provided there's enough lamps. It will probably increase the amount of light reaching the eyes. Which is a good thing.
(Score: 2) by VLM on Sunday March 29 2015, @02:19PM
I also ran some numbers and assuming the lumen output of the LEDs in my living room are not as made up as the lifespan numbers, my living room would have to be the size of a dollhouse. Then I looked in wikipedia and the 500 is extremely optimistic for the most brightly lit office, whereas a typical living room is more like 50.
Also read some of the complaints about the institutionalizing of children, all of which is true, but my kids have no problem accumulating the 3 hrs at (semi-)organized sports and the like. Even gym class at school, lame as it may be, is held outside when possible. And recess at school is outside. I donno, I'm just not seeing the 3 hr minimum as being all that far off from present reality for the average random kid. Maybe in the worst of winter or summer it could be an issue?
Two comments are the demographics of the country and especially of the kids has changed a lot in the last half century despite the claim that genetics doesn't matter. Another issue is diagnosis which is related to medical sector profitability. When glasses were only $5 you can't make a lot of money selling glasses, but now that the whole process has bubbled up to $500 there's profit to be made and there's going to be financial motivation to make sure every kid that could wear glasses gets the money spent on them. So I'm not trusting the statistics trying to make a story sound more impressive.
(Score: 3, Interesting) by mendax on Saturday March 28 2015, @06:58PM
... but I certainly am not an example of this. I'm nearsighted, meaning that I don't need corrective lenses to read but I need them to drive. As a kid, my mom wanted me to be outside roaming around to keep from driving her crazy. I spent a lot of time outside. In my case, it may be genes. My father is nearsighted and also does not wear glasses to read. So was his mother.
Incidentally, if I ditched the glasses and drove without them, my eyes would adjust and I'd likely be able to safely drive without them. I've learned that wearing glasses makes one's eyes rather lazy. I lost them once for a month and my distance vision improved markedly as a result.
It's really quite a simple choice: Life, Death, or Los Angeles.
(Score: 4, Insightful) by Appalbarry on Saturday March 28 2015, @07:14PM
Wow. It's likely not a record, but in a mere 24 comments we've gone from more or less science based discussion to pure unadulterated conjecture and anecdote.
Just for the record, my great-uncle's cousin was hit upside the head with a fastball at a Marlins' game, and it totally fixed his astigmatism.
Therefore I am qualified to say that all near-sighted children should be whacked upside the head.