The Nearsightedness Epidemic

While not the kind of epidemic you're used to hearing about, nearsightedness is becoming a major health issue in many places. Learn about how scientists are finding out the reasons behind the increase in myopia, and how sunlight might be an important component.

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Sources: (pp 18-20)

Views: 765621
Runtime: 8:59
Comments: 3311

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Author Kevin Llanera ( ago)
Yeah sunlight is free, but that doesn't matter if you live in Ireland.

Author Bobby Harper ( ago)
Every time outsiders come into our village these nearsightedness episodes begin.

Author xtin77 ( ago)
What about adults with myopia? Does going out more in the sunlight have any beneficial qualities now that my eyes have stopped developing in my adolescent years?

Author Tobori ( ago)
How many people are going to show this to toeir parents so they stop telling you video games are bad for your eyes

Author eustagoesout ( ago)
educate your sight

Author Beelzebub The One True Demon King Of Kittens ( ago)
kek, anything longer than my arm?, try everything longer than my nose is blurry

Author halfrightface ( ago)
This was published in Dec. 2015. Pokemon Go was released in summer 2016. This is not a coincidence.

Author Linden Bree ( ago)
So I wonder if wearing sunglasses would counteract the benefits for your eyes. And why does it have to be sunlight, I'm guessing ramping up a screen's brightness to obnoxious levels wouldn't have the same effect?
In any case, wow, I'm part of the last generation that can remember the world before the internet went mainstream. I played outside as a little kid and I hated how, when I was an older child, my parents kept making me play sports.
Seems this wasn't so bad after all, I'm now an adult hermit who never goes outside, but my eyes are fine. Probably because a lot of my childhood was spent outdoors

Author Brock Neilon ( ago)
So if a computer or TV screen that produces a more natural light could be a good thing?

Author Christina Walker ( ago)
im far sighted :///

Author Ellie Lawrence ( ago)
We call it short sighted in England

Author Alex Hutchins ( ago)
i have worse eyes than most people out therea corective lens of 5 and 7

Author jay fawn ( ago)
So are you saying farsightedness is results of too much sunlight??

Author Dustin M ( ago)
if sunlight prevents near sightedness then i should have terrible vision but my vision is fine... well fine in the sense that its all i ever seen and that i can read fine but other then my own judgement i dont actually know how good my vision is because i never had my eyes checked

Author Jamie Wilson ( ago)
Here's what I'd like to know: can sunlight help those of us who are already nearsighted stop from becoming more nearsighted?

Author Ray medamiedo ( ago)
Nope sorry, I didn't chose to be myopic... that's how I was born... Lady Gaga told me so... Nearsightedphobic much!

Author Ashley Lunsford ( ago)
So I'm nearsighted and didn't need glasses till high school my childhood I was outside a lot but also was a dancer for 10 years and I'm also the first child and both my parents don't need glasses. I also went from public school to home school in high school right at the time I got my glasses

Author Hr Gwea ( ago)
What about the opposite condition, far-sightedness?
What may be causing that?

Author xtaylorxboyx ( ago)
Who else just focuses on his goatee when he's talking it wiggles so much lol

Author π_Rol ( ago)
Ever since I was a kid I've never been able to stand sunlight. At first I developed farsightedness and I didn't become nearsighted until I began to dedicatedly draw at around age 13.
Despite still using glasses, sunlight simply gives me bad headaches.

Author Nathan Zheng ( ago)
This is one of the best episodes I ever watched thank you!

Author MeanMrMustard1 ( ago)
Whoever thought a guy who looks like a greaser out of the 50s would be so nerdy?

Author Brian Lampkin ( ago)
No1 thought maybe diet has something to do with this? Or am I tripping to think maybe GMO's or shitty foods in general are a cause for this increase?

Author Adinda Ningtyas ( ago)
Im the youngest child and yet only me and my twin are myopic. I spend a lot of time outside and while i get excellent grades . I don't study often. These reasons don't apply to me.

Author Franky Joe ( ago)
I always thought it was because everyone stares at screens these days

Author hitchpster ( ago)
I read "NERDsightedness"

Author emilieloveskiwi ( ago)
I'm a first born and I'm the only one in my family that doesn't need glasses. My partners, brother, aunts, uncles, and all my cousins except for one all have glasses. I feel like I've dodged a bullet! Haha! I'm sure one day I'll probably need them though, but from what I read, the longer you go without needing them, the less likely you are to ever need them, and I'm 23 already! I'd say I'm doing pretty good!

Author Jack Criscione ( ago)
I was told my retina could detach by my ophthalmologist

Author Sergio Ruelas ( ago)
I played in park teams for baseball and soccer most of my youth 10+ years, yet I still have near sightedness. What the shit lol. I started at a later age around 8 however. So maybe in your infant years, sunlight exposure and nearsightedness improvement is more prevalent.

Author musicalturtle1 ( ago)
So what's weird about this dopamine/sunlight hypothesis is that I had 20/20 vision until junior high, when I started getting less sleep and spending a lot less time outdoors because of school. Curiously, I was diagnosed with ADHD a few years later, which is also related to dopamine. Could just be coincidence, but it would be interesting if there was a way to test if there's any connection there

Author azaquihel ( ago)
reading is damaging to our eyes

Author david doroteo ( ago)
It because of vaccines.
To damage our genetics.

Author Aesthetic ( ago)
This explains SO much. when i was a kid i used to go outside daily for HOURS and i had perfect 20/20 vision but as i got older school work started piling up, stress was growing and i started staying inside my house more often and now i wear glasses

Author mechadense ( ago)
If there where better sun-readable reflective displays (crisp like e-ink but colored and with framerates sufficient for video playback) then maybe people would be outside more.

Author mechadense ( ago)
Interesting. But is it the UV part of sunlight that would get filtered out by protective sunglasses or the brightness of sunlight alone? I enjoy self darkening optical glasses. It's rellay convenient when your eyes never hurt after a day of bright summer light. But is that actually a bad choice?

Author Cms2001 ( ago)
I spent plenty of time outside and I'm still super blind

Author Leo B ( ago)
Obviously near-work (reading,smartphone etc) and lack of exposure to sunlight are directly correlated to each other, incredible you didn't even mention this

Author Ekaterina Naumenko ( ago)
Well, I figured out what to do outside - I listen to audiobooks and music. I don't know if this can help my eyesight - I'm already an adult, but my headaches have gone O_O. Thanks, SciShow:)

Author Peter Peter ( ago)
I am stupid and a bum living on the streets yet I can't see pass my nose. WTH

Author Ramkakh ( ago)
So the people in Finland is blind?

Author What Up Its Shanaenae ( ago)
I always wondered why I am near sighted but now I know thanks to this channel

Author Maximilian Wicén ( ago)
I wonder if there's a negative correlation between myopia and different eye conditions like cataract

Author Anku Jb ( ago)
fly kite to avoid myopia

Author Anku Jb ( ago)
CRT monitor, GTA san Andreas , NFS most wanted playing all night caused myopia

Author AntiqueUnicorn ( ago)
I recently needed glasses since taking up science at university. more hours indoors. here's hoping I can reverse the damage!

Author Darshan Sarwade ( ago)
there is something we do in India called Surya Namaskar its a part of yoga

Author Bianca G ( ago)
But wouldn't that mean that in Northern countries where sunlight decreases a lot during Winter we would expect to see a lot more nearsightedness? Is that the case?
Also, if dopamine is involved, people with certain mental health disorders or learning disabilities should show a higher incidence of myopia as well, right?

Author Matty McGoo ( ago)
is there a follow up to this?

Author KittyXD ( ago)
Just invent some eye drops that allow people with myopia,to see normally.

Author ASM Kalrizion ( ago)
Possibly have some input since my friend is near sighted. Sitting in a dark room staring at a bright screen for elongated periods of time with either lack of sleep or an irregular sleeping schedule such as sleeping from 3pm to 10pm instead of 10pm to 7am

Author Madison Hall ( ago)
Well, I spent my entire childhood playing outside, and I still can't see clearly past the end of my arm without my glasses.

Author beccabunny09 ( ago)
I can't believe you didn't mention the most obvious reason about why parents didn't send their kids outside in Guangzhou province: it's one of the most heavily polluted environments on the planet. They didn't send they kid outside because they *love* their child and didn't want them to have a asthma attack or stroke both common for the area. This is sure to become a bigger American problem as the new tump administration finds new ways to rape the EPA of its funding.

Author Feona Johnson ( ago)
so....nerds do wear glasses

Author montork ( ago)
excersize is good for them anyway..

Author Melinda H ( ago)
Well I'm gonna go outside and hope it cures me because contacts and yearly eye appointments are expensive

Author ZDoubleXZ ( ago)
If you need glasses and your mom won't let you get on get a glass cup and put it in front of your eyes

Author Mario Paul ( ago)
Goodbye youtube

Author Yo Lo ( ago)
This doesn't make sense I live in Alaska. Everyday as a kid I would wake up early go outside till 10 or 11 ( which is when sun sets). The sun is out constantly yet I can see less than a foot in front of me without glasses. I also have a twin and he is a lot more active than me yet has worse vision. These stats aren't adding up to my family. In fact, they are backwards.

Author iiMuffinsaur ( ago)
I'm nearsighted. Very nearsighted. Its blurry like a foot away.

Author ThatOneGirl Deanne ( ago)
I both agree and disagree with the sunlight thing. See, I have two brothers, one older and one younger. Me and my younger brother wear glasses, with me having a higher eye grade than him. The fact that my elder brother doesn't wear glasses disagree with the firstborns having higher chances of nearsightedness. I understand that my elder brother doesn't need glasses since he liked staying outdoors when we were kids but the contradiction here is that my younger brother likes going outdoors as well. I have no qualms about myself having higher myopia since I disliked going outdoors since I can't do anything strenous to my body. But it bothers me that my younger brother's eye grade further increased when he got into highschool when he started getting even more chances of going outside since he took a passion for outdoor basketball. It's a nice theory but there are certainly flaws in it.

Author Frikiman ( ago)
You know, it's probably not such a good solution to tell Chinese kids to go outside. I mean, with all the pollution and that.

Author Jon Walker ( ago)
Hank should've hosted this because he has glasses lol

Author Ellie Griesemer ( ago)
Here's a fact:
I'm 14, first born, and have been near-sighted since I was 5, and as of today my eyesight is getting significantly worse. My parents are not nearsighted, and I have sensitive blue eyes, so I don't tolerate light as well as other people. I also live in America.

I'm just a tad bit concerned about your research

Author Isabella Ybarra ( ago)
I'm a middle child, with far sighted parents, play an outdoor sport, get a middle class education, and got glasses in the 1st grade...SO WHY AM I SO NEAR SIGHTED?! 😂😂

Author Dutch Netherlands ( ago)
Everyone look up the "Bates method" it's good stuff.

Author Sarah Farron ( ago)
I can't see a thing without glasses i dunno if education is the problem i didn't study a lot at all but i was an artist drawing outside for hours of course i was outside a lot i also was extremly active :/ so sounds like people who are depressed get there light taken away 😱

Author spongebob cringepants ( ago)
Michael and Hank are good hosts. Olivia's getting better.

Author Lance McClain ( ago)
Not only do I have myopia, but I also have astigmatism in both eyes so sunlight probably wont do much for them :/ Damn...

Author PeppermintGlow ( ago)
So if you don't go out into sunlight, you can go blind. But if you do, you could get skin cancer. But if you don't, you could get depressed from lack of vitamin D. But if you do, you're more likely to develop wrinkles.

Author MissyAmy88 ( ago)
This sucks for me who lives in the artic where there is no sun in the winter.

Author john smith ( ago)
I thought prince Philip figured out why East Asian's had poorer eyesight a long time ago, lol.

Author theinufire ( ago)
I got an ad for prescription glasses on this video, clever Zenni, clever.

Author Kyrstal Watson ( ago)
Does this guy have shakey hand syndrome?

Author SPNOUAT ( ago)
My nearsightedness was likely inherited. My Dad has the same issue (he shared most of his skin/eye/teeth issues with me lol - though fortunately to a lesser severity in all cases it seems). I spent a lot of time outdoors in the sun as a kid biking, walking, & generally running around, and despite that I started to notice I was losing my ability to see far in the 5th grade, way before I started spending more time indoors. (Or rather my teachers noticed - preteen me didn't realize why I was having trouble reading what they wrote on the board). So it's very unlikely that sunlight played any role in my case.(I also have dry eyes that get worst as I age - same as my Dad).

Author Omavektor ( ago)
Why wasn't this knowledge widespread like 20 years ago? Actually, why isn't this common knowledge TODAY? If it's all true, then in Northern latitudes where I live and there's much less sunlight in the winter outside it should be almost mandatory to do outside activities. By the way, it seems that if violet and UV light help to prevent myopia the most, then UV resistant lenses may work against it!
Background: Read a lot of books & stayed inside between the ages of 5 and 15. Sight dropped from 0 to -6 D at the same time, and more or less settled on -7 D for more than a decade. Done prophylactic laser against risk of retinal detachment (still at risk). Parents around -2 and -4 D.

Author John Doe ( ago)
Wait does this explain why nerds so often need glasses

Author John Doe ( ago)
Hey I was born with myopic astigmatism it's not due to any other factors

Author Amit Athi Kesavan ( ago)
So if I go outside more my nearsightedness while be reduced or cured?( ͠° ͟ʖ ͡°)

Author Omar 1111 ( ago)
my dad is longsighted and me and my brother are short sighted I have really bad vision I can't see upclose and I got it at the age of 7 I used to go outside alot as a kid but I became short sighted before my brother who is older than me is the sunlight theory real or should I just blame genetics

Author Fabulous Unnie ( ago)
"So if you want to stop your kids from becoming near sighted, maybe sign them up for soccer." Or just read next to a window that faces the sun during the day if they have social anxiety.

Author Bazza Cipher ( ago)
#Vitamin D overload

Author Helium Valentine ( ago)
the first born hypothesis is wrong. my 4 years older sister never needed glasses, did better in math than me. I needed glasses in 8th grade.
but I inherited from my dad, who needed glasses at a younger age, but my eyes went twice as worse as his.

Author High Warlord ( ago)
I had 20/20 vision, Until I stayed inside, for around 6-7 years (mostly spent in front of my PC, Due to anxiety/depression) GG EYESIGHT I've gotta wear glasses blep

Author Jackie house ( ago)
I've had glasses since I was 9, iPads weren't even invented back then

Author ColonelTerabyte ( ago)
Doesn't going outside also naturally provoke your body to focus on details in the distance?

Author Ferus Plays ( ago)
nearsighted persons with 0.25-2 is nothing . i have 5.25/10 nearsightedness and i can't see far things but miopa is not blur

Author Mark Lewis ( ago)
By that logic, it would seem that I could cure my farsightedness by avoiding the sun. ;)

Author Machiavelli 2050 ( ago)
Remember kids, don't study too hard or you're going to wear glasses for the rest of your life

Author Zhan Heng Lau ( ago)
At least my eyes aren't that bad... and I'm from singapore

Author ColorAmber ( ago)
I was born very farsighted so nearsightedness helped my eyes return to normal lol

Author mlq1718 ( ago)
Hi I'm nearsighted

Author Teabag Der Teebeutel ( ago)
So, if you already are nearsighted and go outside a lot and expose your eyes to sunlight, does your nearsightedness go away or at least gets better?

Author Rebel's Paradox ( ago)
This is just stupid speculation... Come On humans, we have been alive for more that 2 centuries now and yet we cant still answer basic questions.

Author Pobody's Nerfect 麦わら帽子 ( ago)
Sunlight is indeed healthy. Dont have to do it too much, just spend time outside a few times a week👁👀👁‍🗨

Author Sally Philpin ( ago)
I come from a family who all are near sighted, I have 3 older sisters and the 2nd born sister and I both have worse eyesight than my other 2 sisters. We were brought up in the countryside and spent a lot of time outdoors as children.

Author Paulo Silva ( ago)
Did anyone investigated the effect of subjects doing their usual "near work" outside?

Author Julia Lerner ( ago)
So the study hall and the game consoles should be in the atrium.

Author Shavono ( ago)
and vr is about to make it a lot worse. think about it: a screen about 3 inches from your face.

Author Dominique Dupuis ( ago)
will a UV lamp help? Also my glasses block UV light...

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