The Nearsightedness Epidemic

  • Опубликовано:  Год назад
  • 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.

    Hosted by: Michael Aranda
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    Sources: (pp 18-20)
  • ОбразованиеОбразование
  • Длительность: 8:59
  • SciShow  science  Hank  Green  Michael Aranda  Myopia  Blindness  Epidemic  Sunlight  Sports  Preventive Medicine  Eyeball  Optics  Education  What causes nearsightedness?  nearsightedness  The Nearsightedness Epidemic  Near-Work  High Myopia  East Asia  First-born  

Комментарии: 2 838

  • Bonaventure Duprat
    Bonaventure Duprat 2 дня назад

    Is is possible that sunlight and outdoor activities reduce stress and the stress is what causes the eye problems?

  • Kwandaioha O.o
    Kwandaioha O.o 2 дня назад

    I guess I'm the exception XD I'm from Florida and my parents had me in preschool from age 2 and piano lessons from age four. I read a lot. Like hours a day. My parents didn't let me watch much TV. I did spend a lot of time outside though especially in summer working on relatives farms. I'm not near sighted but I've been severely far sighted since I was 9. I'm so far sighted I need glasses all the time and even when driving.

  • KendrixTermina
    KendrixTermina 3 дня назад

    I did always wonder how the hell all those ppl with bay eyesight lived in ancient times if they couldn't hunt or gather very well. Turns out it was just less common.
    The obvious cheat would be to read or study outside or in a room with huge windows, like a screened porch.

  • KendrixTermina
    KendrixTermina 3 дня назад

    So the "nerd or bookworm with glasses" stereotype might be related to ppl with such interests spending more time inside

    ...actually my siblings are all near-sighted bar one (probs genetic reasons, half our father's family wears glasses), and the strenght of our glasses does seem roughly proportional to the level of indoorsy-ness. This, at least, bodes well for our somewhat outdoorsy youngest sister, she might not need thicker glasses as quickly as the rest of us XD

  • Marilla B
    Marilla B 4 дня назад

    Our myopic ancestors were eaten, killed or involved in deadly accidents and were unable to pass on their myopic genes. Now that is not the rule and therefore more and more myopics are passing on their myopic genes.

  • Amy Hudson
    Amy Hudson 5 дней назад

    Huh, dopamine.
    So I have near-sightedness because I'm depressed?

  • Andrew Cady
    Andrew Cady 6 дней назад

    Or we could use those bright lights that they used on the chickens to light our indoor spaces.

  • Chrisly3ear
    Chrisly3ear 6 дней назад

    Well it could also be the case, that if you're outside, you'll "flex your eye's muscles" more than while being inside. If you're outside there are a lot more different distances your eyes need to switch focus between. If you're inside, well, not so much.
    (I'm at 5:46 in the video. Maybe this will be brought up.)

  • champnewt
    champnewt 6 дней назад

    Spent all my time outside as a kid. By third grade I needed glasses.

  • GambyThe4th
    GambyThe4th 7 дней назад

    I'm 19 years old and in college with near-sightedness. I was diagnosed with it in 3rd grade and I was a pretty active kid. The weird thing about it is that all 3 of my siblings aren't near-sighted: and I was more active than all of them. Since my mom is near-sighted, I think genetics does contribute to this epidemic one way or another. I could just be miraculously unlucky but it's just too uncanny of a coincidence.

  • Susan Farley
    Susan Farley 8 дней назад

    Played outside all the time when i was a kid. My mom told me i had to come in when the street lights came on. Ended up nearsighted anyway.

  • Rob Delgado
    Rob Delgado 8 дней назад

    its from reading maybe? were so brainwashed into just looking down at words on a page when we should be looking up and out into the universe, this is where we will find the answers not looking down we have to look out.

  • Michael Meissner
    Michael Meissner 11 дней назад

    Question: can myopia be reversed to any degree without surgery? My eyesight is somewhere around 20/400 (-5.00 and -5.25 with my contacts), and I know that my brother, who had a far worse prescription, was successfully corrected to about 20/25 with surgery. So surgery certainly is an option for me, but it would be really cool if it can be corrected even to a slight degree by natural conditioning.

  • springxdeerling pkmn
    springxdeerling pkmn 11 дней назад

    Damn he cute

  • Errol Candelaria
    Errol Candelaria 11 дней назад

    His voice is so relaxing 😴

  • Matt Parker
    Matt Parker 12 дней назад

    I'm an elementary science teacher. I'm going to add this information to the list of reasons I am pushing for my school to build an outdoor classroom.

  • Genoch Tuason
    Genoch Tuason 12 дней назад

    basically useless vid,

  • Blacksquareable
    Blacksquareable 12 дней назад

    Alliance Optikk actually look at this phenomenon on their Facebook site. They are very much mainstream and quote, "too much reading and close screen-work tires the eyes and can lead to shortsightedness." That's official.

  • GusGus
    GusGus 16 дней назад

    You look like Mike Shinoda

  • Seth Biggs
    Seth Biggs 16 дней назад

    So glasses do mean you are smart

  • Adam Kee Ooi Yuen
    Adam Kee Ooi Yuen 16 дней назад

    Hmmm... I have high myopia and I need to wear super thick glasses. To be honest, I can sometime stay in the house for days...

  • Tim Gooding
    Tim Gooding 16 дней назад

    I would have spent 4-5 hours a day in the sunlight as a kid. This is the norm for an Australian kid. Or was before the x-box playstation etc.

  • Pete Ramirez
    Pete Ramirez 16 дней назад

    This complicates long duration space travel.

  • Hunter Bowman
    Hunter Bowman 16 дней назад

    All these YouTube scientists in the comment section, think they know more than actual scientists

  • bep nop
    bep nop 16 дней назад +1



  • Emil Sørensen
    Emil Sørensen 17 дней назад


    I'll take retinal detachment, thank you very much!

  • Motalux
    Motalux 18 дней назад

    I'm near sighted...

  • Joshua Schmidtke
    Joshua Schmidtke 18 дней назад

    don't stare at the sun huh? i did it all the time when i was a kid and i have 20/15 vision. eat it.

  • Daniel Lee
    Daniel Lee 18 дней назад +1

    Wait so if im smart then....that explains my blur vision? ;-;

    • Daniel Lee
      Daniel Lee 18 дней назад +1

      Also i only understand like half of what he said because im confused

  • Sabina Hertzum
    Sabina Hertzum 18 дней назад

    If there are so many people with nearsightedness - then why is it so hard for eye glass wearers to find cheap glasses....
    It's been a pet peeve of mine... every drugstore or even supermarket have glasses for long sighted ( + ) - but to find cheap glasses for nearsighted ( - ) is almost impossible or they have a tiny supply... why is that???

  • Austin Duong-Van
    Austin Duong-Van 19 дней назад

    But...but I stared at the eclipse like Trump and my eyes are damaged!

  • Meep
    Meep 19 дней назад

    Global Warming?

  • Amplitude
    Amplitude 19 дней назад

    tfw -6.25D in one eye and -6.5D in the other
    i should have gone outside

  • satoau1
    satoau1 19 дней назад

    hmm... going outside works, sunlight could be part of it, better outcomes in sydney than singapore... maybe likely it's the use of far sight that's preventing it? if you stay inside the furthest thing you focus on is the wall, and if you've ever been to asia you will have noticed that the furthest thing you can see is the building across the street, or maybe a bit further if there's a flat and straight enough bit of road, which is very uncommon with the mountainous terrain.

  • The Meem
    The Meem 19 дней назад

    "sunlight and proper day/night cycle is the best idea" the video playing says on my 35% brightness iphone in a completely dark room with closed curtains at 4:00pm

  • Deanna Demers
    Deanna Demers 20 дней назад

    There seems to be some genetic predisposition....but neither parents were nearsighted

  • Deanna Demers
    Deanna Demers 20 дней назад

    It may also be because when outside you focus far away and your eyes are exercising...I am very nearsighted and always did close work...reading sewing embroidery etc. But all my kids needed glasses or contacts. None are as bad as I am

  • Grass Hope
    Grass Hope 22 дня назад

    I'm farsighted O-O

  • Damitha Nadeesha Wanniarachchi
    Damitha Nadeesha Wanniarachchi 22 дня назад

    \So is it possible to cure or reduce myopia in adults also? (20yrs to 30yrs)

  • MBailey ESL
    MBailey ESL 22 дня назад

    Yes, the quality of the light is a factor, so sunlight is good. But I think it also has to do with what can be done outside. For example, if you are playing catch, you have to focus your eye far away (friend with ball) middle distance (ball in motion) and close (ball entering glove or fast approaching it). This is similar to exercises done to maintain eye strength (focusing on objects at varying distances in succession). I think the fact that the eye gets more exercise outside has to do with its resilience.

  • areamusicale
    areamusicale 23 дня назад

    7:40 Ahahah ! Parents nowadays are too afraid of terrorists and paedophiles.
    They won't let their kids going anywhere without their supervision.

  • Zom Bee Nature
    Zom Bee Nature 23 дня назад

    I am very nearsighted and don't go outside and I have little vitamin D in my system
    Please watch my tiny nature videos. There is no talking in them. Shhh!

  • glytchd
    glytchd 23 дня назад

    @Sondrex76 As with most things, the truth lies somewhere inbetween
    Stereotypes exist for good reason. Unfortunately, dumb-dumbs like to apply stereotypes either to Everyone OR go full PC-Police and say you cant use them at all. Both extremes are, obviously incorrect.

  • Peregrination
    Peregrination 24 дня назад

    Alas, a childhood spent outside in the lovely mountains of Colorado hiking, horseback riding, and just playing did not save my eyesight. But then again, I'm not blind without my glasses like my mom who spent her Canadian childhood figure skating in indoor rinks.

  • Nekros
    Nekros 24 дня назад

    I don't spend any time outside and my eyes are fine.

  • Sarah Langlois-Luna
    Sarah Langlois-Luna 24 дня назад

    I got mine by reading in bed, laying on one side... I'm nearsighted in only one eye...

  • shanefm02
    shanefm02 24 дня назад

    Well I'm already at 20/300 before I'm out of highschool and I spend a lot of time outdoors so I think I'm just plain unlucky

  • donthaveone donthaveone
    donthaveone donthaveone 25 дней назад

    i like cold hand around my knob - what a waste of money! just jerk off a hard cock!

  • Michael Harig
    Michael Harig 25 дней назад

    Why not promote gardens?? instead of baby wars called sports that teach a superior & inferior mindset...

  • adiya mandor
    adiya mandor 25 дней назад

    its good that you use green background 😎

  • MrGallade475
    MrGallade475 25 дней назад

    so at 18 is it too late for me to do anything about it?

  • keana dennis
    keana dennis 25 дней назад

    could staying inside correct farsightedness

  • James Barker
    James Barker 25 дней назад

    I wonder if they controlled for the use of sunglasses in any if the studies. Presumably, the wearing of sunglasses would reduce the benefit of the sunlight--unless the dopamine benefit doesn't come through the eyes exposure to sunlight but through some other body part like the skin.

    Notably, I am under the impressiln that the use of sunglasses, even in younger people, has become much more prevalent in the last couple of decades or so. In fact, we are encouraged to have our children wear good quality sunglasses to protect their eyes. Could this be contributing to the near-sightedness epedimic?

  • ResortDog
    ResortDog 25 дней назад

    A lot more likely they are focusing further away more often in A. Maybe that affects light intake too, but use seems more likely than environment sun or not or city light instead of far away light AND genes remember their parents life too.

  • NO.
    NO. 25 дней назад

    I never go outside, am nearsighted, glasses, and people call me a nerd. The stereotype has been completed.

  • Skye blue16
    Skye blue16 26 дней назад +1

    (2:48 in the afternoon watching this as a break from chemistry homework) rushes to blinds and lets the burning sunlight inside.

  • kirk white
    kirk white 26 дней назад

    Dam I'm nearsighted but my brother is not and he did spend more time outdoors than me but I was always the smarter one. I never realised but it all makes perfect sense now.

  • e8root
    e8root 27 дней назад

    evening, just before sunset when sun is much dimmer than during the day:
    look at sun directly for some time. Big sub sized sunspot that make
    nothing to be visible in this spot does fade and surprisingly rather
    quickly. I watched sun for long ennough to actually make eyes really
    feel it as burning. Still it actually made everything look better, not
    worse. And it actually took a little while, few minutes of watching sun
    and not sunset but actual sun when it was still rather high in the sky.

  • Haruko Haruhara
    Haruko Haruhara 28 дней назад

    That's funny because I became nearsighted in 3rd grade and ever since starting to stare at computer screens, smartphones and the like, it has actually stopped becoming any worse! It runs in the family though, so I guess my anecdote doesn't speak for everybody. Still, the only reason I get new glasses anymore is because my astigmatism likes to slightly change its' position over time.

  • Wizard Clip Audio
    Wizard Clip Audio 29 дней назад

    Uhhh,... maybe it's not so much that reduces nearsightedness but, being outside in the daylight effectively gives your eyes more distant things for your eyes to focus on?

  • psushgirl
    psushgirl 29 дней назад

    i also wonder if the fact that cities like Beijing, China have a lot of pollution also contributes to this. for example, when the pollution days are really bad, kids are kept indoors at school and at home. and if the pollution gets bad enough, school is canceled. this would account for a lot less exposure to sunlight than someone who lives in a less polluted city. fascinating!

  • Robert Pyrosthenes
    Robert Pyrosthenes Месяц назад

    What about actual squinting? Being outside often causes one to squint to protect their eyes from bright light and this puts pressure on the front of the eyes. Maybe myopia is prevented by reshaping the eyes by putting pressure on them?

  • Zamp Magic
    Zamp Magic Месяц назад

    Could this also be influenced by childhood dipression?

  • craigistheman101
    craigistheman101 Месяц назад

    We are evolving

  • Garrett Norris
    Garrett Norris Месяц назад

    every day as a kid I sat on the right side of the bus, something just felt wrong sitting on the other side. I always took the window seat and had the right side of my head leaned up against the window. this was how I did things every morning and every afternoon for about 13 straight years. now my eyes have two different prescriptions - the left eye is a little worse than the right. could this be related?

  • Catherine Gasiorowski
    Catherine Gasiorowski Месяц назад

    Woah where's your white hair

  • Darth Musturd
    Darth Musturd Месяц назад

    I'm nearsighted

    • Darth Musturd
      Darth Musturd Месяц назад

      And I am good at math and spend a lot of time indoors

    • Darth Musturd
      Darth Musturd Месяц назад

      And it's 9:11 p.m.

    • Darth Musturd
      Darth Musturd Месяц назад

      I'm also a firstborn

    • Darth Musturd
      Darth Musturd Месяц назад

      I'm also watching this video on my iPad.

  • Mr.EDM
    Mr.EDM Месяц назад

    100% of kids born in the UK are nearsighted.

  • Lovi Poekimo
    Lovi Poekimo Месяц назад

    I hate this jacket on Michael. Please take it off. And your shirt too.

  • echelon2k8
    echelon2k8 Месяц назад

    So, if you already have myopia, even as an adult, can spending more time in sunlight help it from getting even worse?

  • J Espinola
    J Espinola Месяц назад

    *looks at eclipse*

  • J Espinola
    J Espinola Месяц назад

    6:20 *turns up brightness*

  • Brooke-chan
    Brooke-chan Месяц назад

    Well, looks like I’m going to go blind. xD

  • Ryan Rodriguez
    Ryan Rodriguez Месяц назад

    So looking at the eclipse might have helped?

  • ABCantonese
    ABCantonese Месяц назад

    The kids in Sydney did more work than those in Singapore? Really?

  • Charles Wang
    Charles Wang Месяц назад

    Simple solution- conduct class outdoors.

  • Pensivity
    Pensivity Месяц назад

    So could it be possible to reverse myopia by spending more time in the sunlight or is it just good to prevent myopia?

  • Pi Van
    Pi Van Месяц назад

    Does that also mean that people in northern countries are more shortsighted? Because you obviously have less sun when you live in Scotland compared to someone living in Italy!

  • Misc.Viewer
    Misc.Viewer Месяц назад

    So kids spending much less time outside then they used to. Thus eyesite is getting worse

  • knightshousegames
    knightshousegames Месяц назад

    Now what I want to see is a study of the kids who actually played outside during recess vs the kids who played Pokemon on their Game Boys under the playground equipment.

  • Dragonofshame
    Dragonofshame Месяц назад

    It's amazing to see just how many people in the comment section completely missed the point the video was making, even though you covered it multiple times.

  • zodiacfml
    zodiacfml Месяц назад

    I quite agree with this study. I experienced this during a drastic change to my lifestyle where I have to stay indoors pretty much 95% of the time for a year already. I found that my vision for long distance has been noticeably impaired at a far distance with artificial light. Though it is not too bad in good light such as during daytime.

  • Alexei Soltis
    Alexei Soltis Месяц назад

    I was virtually always indoors as a child (and nowadays too) AND I'm the firstborn. No wonder I have Myopia.

  • Sunny Lovett
    Sunny Lovett Месяц назад

    Seems probable (to me) that the benefits of being outside have as much to do with the eye focusing on far away objects, from trees over the fence to the sky itself, as it has to do with sunlight. Almost certainly its a combination of sunlight and the long range focusing.
    The way to test this theory is fairly simple and also difficult to achieve. Find children that spend a lot of time outdoors at night but rarely go out during the day. Astronomy fans perhaps.

  • Munk
    Munk Месяц назад

    Being outside sucks. Let's find something better.

  • oxnard_flossifer
    oxnard_flossifer Месяц назад

    I played outdoor sports all throughout middle school and high school and still developed -4.0 myopia with little to no genetic influence from my parents.

  • Lumpy109
    Lumpy109 Месяц назад +1

    Brighter stimulation of the Iris prevents blindness? Interesting.

  • Christopher Stoltz
    Christopher Stoltz Месяц назад

    How can he say video games don't cause it when the reason kids aren't outside is because they're inside playing video games!

  • sgtlawl
    sgtlawl Месяц назад

    So dopamine helps the development of eyes, Ritalin reduces dopamine levels. So having been on Ritalin, it may have very well played a role in me becoming nearsighted.

  • DeformedBear
    DeformedBear Месяц назад

    Just stare at the sun. Got it.

  • pro gamer
    pro gamer Месяц назад

    If I stear in to the sun I will not need glasses

  • pro gamer
    pro gamer Месяц назад

    so that's the reason why I wear glasses, because I don't play that game that's called outside

  • Bryan Rosales Bush
    Bryan Rosales Bush Месяц назад

    QUESTION! If sunlight can help reduce the effects of myopia, does that mean too much sunlight can cause hyperopia (far sightedness)? Both of my parents are far sighted and I'm near sighted. Which is weird to begin with with the genetics of the problem. However, both of my parents were raised on farms and were exposed to plenty of sunlight for the vast majority of the developmental part of their lives. I on the other hand stay inside reading a book or on some form of an electronic, giving me next to no sunlight. Does too much sunlight cause hyperopia?

  • Etsu Very Lucky
    Etsu Very Lucky Месяц назад

    sunlight? try going out for a in singapore and tell me that kids in singapore are not getting enough sunlight

  • William Waffle
    William Waffle Месяц назад

    Only 3 hours in the sun a week?

  • 2Awesome
    2Awesome Месяц назад

    Is it because of the sun or because you have multiple distances to focus on all the time while you are outside?

  • Pepins Spot
    Pepins Spot Месяц назад

    So it begs the question, do kids that play outdoor sports less myopic?

  • John Matthias
    John Matthias Месяц назад

    Could it simply be that playing outdoors 'exercises' eyes with frequent changes of focal length, causing the shape of the eyeball to be rounder over time?

  • Eric Ji
    Eric Ji Месяц назад

    So should I not wear sunglasses?

  • NotSoFamous
    NotSoFamous Месяц назад +1

    I stared at the sun today, NOW IM BLIND, Thanks Obama