Almost all children are born hypermetropic (far-sighted). The growth of the eyeball is calibrated by the amount of defocus (blur) experienced. More defocus, more growth, which reduces hypermetropia.
My hypothesis is that less sunlight means wider pupils and more defocus (contrast to a pinhole camera), so more eye growth.
Even with perfect eyesight, there's a 2-diopter difference between focussing blue light and red light due to chromatic aberration. Only narrow pupils can reduce this blur in white light.
I'm also curious whether older TVs with big blurry pixels (or low res images upscaled and smeared onto newer screens) trigger the same mechanism. These days I certainly feel physically uncomfortable looking at media like that, like my eyes aren't focussing quite right.
The other problem is that once eyes have grown too long and are myopic (near-sighted) they experience even more defocus and grow more. See for example [1] which discusses how under-correction of myopia accelerates progression.
So i'mnot sure if / how your theory is correct or not.
Also there are a lot of normal people in the world who live outside and also don't have perfect eye sight at all. This goes back a long time.
Can you also elaborate on your 2 diopter difference between red and blue light? For one i find that number very very big but i'm very good in seeing full color without any chromatic aberration.
The effect of your theory would need to be less relevant than other factors.
Not denying that there are many ways in which development can go wrong, whether that's genetic or the environment. What I'm responding to is the sudden change seen in many populations as per the article.
They measured 1.82 diopters between 420nm and 660nm. Visible light is a bit wider, 380nm to 720nm, so 2 diopters is about right.
You easily can see this in a dark data centre. If your vision is perfectly corrected (which normally means perfect for red-green light) you won't be able to focus on a blue LED unless you are about 50cm away.
Pure blue light does the least to stimulate the rods that help you see shapes clearly, only activating blue cones. This is why compression algorithms and some screens use 2 or 4 times as many bytes or phosphors for green as they do for blue https://biodifferences.com/difference-between-rods-and-cones...
This is also why writing a word in pure blue neon lights is really dumb. Adding just a little bit of green to it helps readability immensely.
I'm really interested in this topic since I've always noticed this, but not sure about this explanation as to why. I mean, yes, Bayes filter is like 2x1x1 for green, *red* and blue, and the most popular explanation has always been that our eyes perceive green better than both red and blue. Yet I don't have issues with red LED lights.
Well, everything is genetic. The amount of sunlight you're exposed to is no less a genetic effect than how tall you grow to be. Without genes, you wouldn't have any behaviors or phenotypes at all.
So the interesting question is not "is this phenomenon genetic?", because the answer to that is always "yes". The interesting question is "what can influence this phenomenon?". In this case, we already know that (1) within a given culture, genetics are a strong predictor for myopia; and (2) once you do a cross-cultural comparison, the effect of culture absolutely overwhelms genetic measurements. Most people who become nearsighted in modern cultures would never become nearsighted in premodern cultures.
> Genetic predisposition to something != inevitability.
That depends on the thing. Whether you grow five or six fingers on your hands is determined by your genes without much reference to anything else. Whether you reach a "natural" height or develop stunted by malnutrition is also determined by your genes. It is more responsive to environmental conditions than the number of fingers on your hand is - but that responsiveness is determined by your genes.
Genes can cause or prevent myopia. However, genes do not spread rapidly and therefore cannot cause an epidemic. Obviously environmental factors are the major cause.
I think there's genetic predisposition but unless you have a separate disease, myopia is unlikely to just emerge out of thin air. There's probably something that we do that harms our ways and the studies point to the time outside as the key factor (screen time was just a correlation).
Something like this is beginning to be accepted. At least that's the impression I got from the eye doctor when I had PRK surgery. FWIW I had 20/15 vision until starting college and consequently being indoors in the dark much more often (staying up late to program).
I wore glasses for a few years in high school because I had trouble seeing the blackboard from anywhere but the front row. I started hiking and kayaking every day, especially in places where I could see for many miles. I also migrated from CRT to LCD to LED screens, and more recently to e-ink devices when possible. Very fine print in a dark space is hard to read, but I can read a moving US license plate from six blocks away. Yesterday I recognized a friend a mile and a half away by their paddle-stroke. I am able to differentiate a bald eagle from an osprey at two miles based on the shape of the wings, and see a fish in talons at about a mile. (Friday I observed an osprey dive, catch a fish, head towards the nest, then get chased for thirty minutes by a bald eagle. Nasty, opportunistic birds, bald eagles. I get why Benjamin Franklin held them in such contempt. I lost the pair when they went behind a mountain about three miles away.) In speaking with ophthalmologists, there is wide support for my hypothesis that the near-daily outdoor activity and frequent change of focal distance–from a nautical chart on my foredeck to the bow wave of a tanker eight miles out–has preserved and likely improved my vision. The data: 20/20 in primary school, 20/23 in high school, 20/20 during my higher education, and 20/13 and improving as I approach retirement. A fun trick is to describe an approaching vessel before others have seen it.
I am able to differentiate a bald eagle from an osprey at two miles based on the shape of the wings
I wonder how you judge the distances? I'm a helicopter pilot and I don't even bother looking for traffic farther than 2 miles out unless it's an airliner. I have radar telling me how far away they are so I know the distances are accurate.
I know the estuarine river very well in my part of the world and the approximate distances between various landmarks and aids to navigation. Places I don't know as well, I use nearby features: cars, houses, aids to navigation, etc., to approximate. Exact accuracy isn't critical as normal cruising speed is around four knots. I know the distance from the George Washington Bridge to the Statue of Liberty is about 12 miles, and about ten miles from the GWB to the Battery. It is about six miles from World's End to Anthony's Nose and the Bear Mountain Bridge. It is about 1.5 miles from Little Stony Point to Pollepel Island and another 1.5 to Denning Point.
I also know about how large the various adult birds appear at various distances, recognizing that there is some variability. If it really mattered, I could carry a range finder.
Navigating in the open ocean, with no landmarks, is a little different. I have two compasses: one on my deck and one in my life jacket with my marine radio. I keep a charged phone with GPS and local marine charts in a dry box in a dry bag in a dry hatch in my boat, but have yet to rely on it. I look up the velocity and direction of the predicted currents and keep a chart of that on the deck along with my navigational chart. I plot my course on the chart and note the headings to my next waypoint. I keep a duplicate of the predicted currents and headings in a waterproof notebook on my body in case the chart gets separated from my boat. I note my departure time and calculate my velocity based on my normal cruising speed, adjust that for conditions – wind, current, company – and go for it.
I practice this on my local waters because I've been enveloped by fog off the coast of Maine. In September 2019 at low tide in the morning, three of us in a line with about twelve inches between stern and bow, we were unable to see the other paddlers in their cockpits, which means visibility was no more than seventeen feet. We navigated by instruments, ocean swell, and wind direction for two hours before the fog burned off.
This makes me wonder: is there a lens that you could use instead of glasses that will make your computer screen appear as if it is further away? Could it help people regain their far-sight?
Sure, get convex lens ("reading glasses") of about +1 to +1.5D and make the IPD as low as possible to induce a prism https://en.wikipedia.org/wiki/Prism_correction#Prentice's_ru... (in layman terms, this will make the "rays" coming from your two eyes "cross" and intersect at a certain distance)
You can also use prismatic lenses as the induced prism probably won't be sufficient (but better than nothing), but my local shop does not make them, so I have no experience with this.
I am shortsighted and I have special glasses for computer/close work (reading, soldering), which are 1.5D weaker and the IPD is 10mm larger (as these are concave lenses, it's the opposite IPD manipulation than with convex). The induced prism for my glasses is about 2Δ.
I don't understand why this is not more popular, both among shortsighted (to have weaker glasses to use indoors) and healthy (to have "reading glasses"). Including the prism. Beware, that some doctors say that by using such "perfect" correction for e.g. your computer screen, your eyes will "get lazy". I don't think this is true, but YMMV.
Protip: there are online services that will just make you glasses, no questions asked, usually for $20 to $40 for basic glasses. Here in .cz we have optiscont, globally, there is zennioptical; you can also search aliexpress. I don't have any apparatus to measure the quality of the resulting lenses, they however seem "good enough".
> I also migrated from CRT to LCD to LED screens, and more recently to e-ink devices when possible.
I too use eInk whenever possible but that's just for reading (a passion of mine). All current computer monitors are LED AFAIK, is there any research tho that it's better for sight, or are you simply stating that you migrated as the technology changed?
I'm thinking that OLEDs are the best looking but one of their weaknesses often mentioned is that they aren't as bright; if you have lots of light (ideally natural sunlight) they may prove to be counterproductive if you have to strain to see due to appearing dim.
More seriously, though, I am not far-sighted. I do not need corrective lenses to read books, newsprint, magazines, or labels at the grocery store despite the possible genetic predisposition baed on the need for reading glasses by my parents and siblings. I often have to read very fine details on nautical charts, sometimes in a seaway, sometimes at night with the use of a headlamp.
Exhaustion definitely changes my eyesight. I'm coming off of two days of kayaking and camping with high school kids followed by an intensive four hour lesson teaching rescues. (Imagine ~3600 boat-poses per hour, then subtract a few hundred and replace them with pulling swamped boats out of the water and across my lap to empty them, climbing out of the water and into the boat to demonstrate a dozen types of self-rescue.) I tried to read last night but my eyes could not focus; I vaguely remember making my way toward bed but woke up twelve hours later downstairs on the floor.
I try to work seven days a week four hours a day for the last ten years. It is an attempt to avoid burnout, but I also find I solve more of the truly hard problems away from the keyboard.
My fantasy setup: waterproof 13"-15" e-ink linux device with 16GB of RAM and mobile connectivity and a Twiddler X Lendal collab on a 210cm Cadence. A rollup waterproof full-size bluetooth keyboard would be adequate. The keyboard and e-ink device would both need tether points and/or internal flotation.
My child is following in my footsteps and has been prescribed glasses for nearsightedness. Her optometrist told us she should be watching TV rather than reading books. This was both surprising and upsetting, especially since she loves reading.
This lead me on an interesting deep dive into existing research. What surprised me were the massive gaps in understanding. Scientist have at best established correlation between close up work and nearsightedness, and a negative correlation with spending time outside. The actual mechanism in play is unknown, for example the theories about sunlight are still untested. The specific types of close up work that cause issues is unknown. Some scientists have proposed that it's the contrast between white pages and black text that actually causes issues with reading.
My conclusion was that anyone who confidently asserts that $x causes nearsightedness is wrong (this thread is a case in point).
After being diagnosed with glaucoma I did a fair amount reading about that condition. My conclusion is that aside from some specific cases (head/eye injury) nobody really knows what causes it, there are probably multiple reasons, it could be a downstream effect from other health problems, and there just isn't a lot of research to sort it out.
Cynically, I feel like there is a lot of money being made just by treating eye disorders the same way its been done for decades. For example, right now, the main treatment I use for glaucoma is eye drops, which is the same treatment given to my grandmother when she was diagnosed in the 1960s. And those drops are not covered by insurance, rather expensive, and I have to take them every day forever, along with twice a year eye exams and visual field tests.
I don't know if this can help you or not, but Mark Cuban's Cost plus Drug Company has 3 different glaucoma drop generics available that may be cheaper than how you're getting it today?
It could help, thanks for that. It looks like the drops I use aren't on there. Problem is, its kind of a confidence game. My eye doc says to me, use brand X drops, they are the best. But they also aren't covered by insurance, and are distributed by an online pharmacy my doc _may_ have a financial stake in (I can't confirm this but I have a suspicion.) So do I ignore her advice and take different drops, which might be cheaper, but potentially have more issues with eyes down the road? I don't know.
For now I've decided to take the expensive brand-name drops, and we're monitoring to see if my condition progresses or not. After a couple years of this I might switch.
Sunlight onbthe retina helps form Serotonin. Has to be direct or through eyelids, not through any glass.
A doctor told me a leading theory about how outside time helps is by shifting focus from faraway to close and back. So look at things up at top of buildings or upper canopy of trees then into some nearby detail back and forth my. It's a kind of excersize for eye focus. My son's eyes have held close to 20/20 into High School. We have good views for this from our apartment. I've taught him to check cornices and close details as he walks to and from school.
I'm not going to speculate on the exact cause but I'm comfortable saying children should have 2-3 recess periods outside totalling at least an hour (preferably 2 or 3) and that the recess periods should be structured to ensure that children spend time focusing on a variety of things at a variety of distances. There's certainly a possibility this won't have the intended effect but it will doubtlessly have a lot of net good effects assuming air quality cooperates.
In my nearsighted family (parents, 2 kids) we've concluded that reading printed-pages makes you get nearsighted faster than reading words on a computer screen.
This seems to work for us. Don't know about anyone else. I'm very nearsighted (-14 diopters), but I grew up reading books on paper.
This comment is exactly what I'm talking about. Studies involving hundreds of individuals is struggling to get that kind of clarity around correlations. The observations you've made with a handful of people are anecdotes, not controlled data.
Honestly, myopia is not complicated (Kepler pretty much had it right in 1604 already). There's countless studies showing that axial length (eyeball length) changes in both directions, where elongation increases myopia. How do you change it? You get defocus (blur) which makes the eye adjust in the direction to reduce the blur.
Practically: use weaker (around 1.5 diopters) or no glasses during close-up work (reading, computer work, smartphones) and your regular or .25D weaker glasses for distance vision. Always use your full strength glasses for driving and safety critical activities.
You can expect around a .75D decrease in myopia per year. Personally, I started with around -5.5D and am now (1.5 years later) at -2.5D.
Obviously I didn't come up with this myself, there's a huge group over at https://endmyopia.org
Don't get put off by the sarcastic tone of the website. Look into the studies regarding axial length, pseudomyopia and lens induced myopia if you'd like. You can find plenty of studies linked as well as the practical steps on endmyopia. Note: You don't have to buy the guy's courses, just read his blog and free email guide.
Hard to believe after all these years EndMyopia is not only being promoted on HN, but is consistently one of the most upvoted things on the subject. I figured the pros here would slice and dice and find issues with the research and recommendations and explain in depth why it’s snake oil (if it is), but it’s been a fairly forgiving topic.
It's bullshit because there are a ton of reasons why you would need corrective vision. This will work for a small subset but for most will not. And for those who it does help, they'll still need glasses. It's pointless.
It's more likely that it works for a large majority. If you were born myopic or had an accident or something similar, yea it most likely wont work for you. But most myopes do not fall in those categories. I'm very open to hearing your arguments backing up your statement though.
My arguments are that if that were the case, we'd already be doing it. I work in the optical industry. To suggest that opthalmologists just haven't figured this out yet is just pants on head retarded, sorry.
We live in a world where not long ago smoking was considered fine by doctors. Where fat is demonized on nutrition labels while obesity surges. Where leaded gasoline was banned in gas not that long ago. Where a dozen diseases are increasingly prevalent and we have no idea why. To suggest that medicine hasn't figured something out is completely sensible. It can be argued that mRNA vaccine breakthroughs might not have happened without COVID, before that we didn't have it figured out. How many ophthalmologists are doing research, and how many are doing their job and going home because research doesn't pay? In every age many are convinced we've reached the pinnacle of science and have everything figured out, and that is pants on head retarded.
I think what the parent is trying to say is that we have studies that show how myopia can be induced. I think EndMyopia gives examples in baby chickens or some such. But I’ve yet personally not come across a vetted study that shows reversal of myopia. And I support EndMyopia/Hormesis Theory as I’ve applied some of the ideas to help my one weaker eye get a bit sharper over time.
I understand there’s an industry that wants to be paid for prescription glasses and lenses and whatnot, and that can throw a wrench and it does into the whole thing - see the Sugar vs Fat vs Whatever industry battle. But a little would go a long way.
I only checked your first article, and you're not wrong that axial length change was observed in humans. But it makes the opposite point of what you hope. The myopic eyes only grew longer when subjected to any type of blur.
"In addition, in myopes, calculated defocus caused longer eyes (+8.4 ± 9.0 µm, P = 0.001). Strikingly, myopic eyes became also longer with positive defocus (+9.1 ± 11.2 µm, P = 0.02)."
Please check out the other articles too or read some more of that article - they point out that their findings are not the norm and speculate as to why that could be. I suspect it's because they used too much defocus (you wouldn't be able to read anything with the amount of defocus they're using, so completely impractical for real life) - that has led to axial elongation in many other studies too.
This probably works for most people. But I've used 2-diopter weak glasses for the last 40 years, whenever I'm indoors. I think it helped slow the worsening of progression of my nearsightedness, but didn't stop it and certainly didn't reverse it.
Congrats! It's already good to stagnate so you dont get into high myope territory, which comes with lots of risks.
Apart from that I'm positive you could make improvements. You'd need to continuously measure your eyesight and adjust your glasses accordingly, otherwise you might undo your improvements by being overcorrected.
Is there a single step-by-step guide that shows what to do?
All I can find on that (frankly quite awful) site are ways to sign up to a course by email, lots of podcast episodes, testimonials for people that improved their eyesight, and endless photos of what I assume is the site's creator. The "Guides" page doesn't actually have any guides, just more of the same.
From what I can tell, the guy really wants to sell you a course, but at the same time, they are all "sold out".
His free 7 day email guide is a good introduction imo (if i remember right, it was 1.5 years ago for me after all). You might also prefer the wiki, which is more seriously written: https://wiki.endmyopia.org/wiki/EndMyopia_Wiki
The red flag for me about how well this all works is that the only way to find out how is to pay money. As you noted, the site itself doesn't inspire confidence either.
I did not pay anything, nor do I gain anything from promoting Jake's work. I do it because it works so well and once found it the same way - from a comment on HN.
I agree that most optometrist won't advise you to do this. However, I don't see that as a good thing:
"Contrarily, academics felt failure to discuss myopia control or refer a progressive myope for myopia control treatment was verging on negligent..."
In my early teens I had 20/15 vision. By the time I went to college I was wearing glasses for nearsightedness.
I'm pretty sure it's because I got interested in computers, and started spending all day staring 3ft ahead instead of glancing around outdoors.
Some friends in my computer science program passed around each other's glasses and found we all had nearly the same prescription. That didn't seem like a coincidence.
That may just be lucky coincidence. I've been a computer nerd spending way too many hours in front of my computer since I was a teen. Last eye exam I had was a few years back when I turned 45. 20/20 in one eye, but after I made a remark about having been 20/15 when younger, the tech said "let's try!" and I could still do it. Barely. In only one eye now. But still, after all these years.
But really it's presbyopia that's bothered me. I'm glad my distance vision is great, but the loss of close-up focus is massively inconvenient. Reading glasses make me want to throw up within a matter of minutes. Not sure what my long term plan is aside from suffer.
I still have 20/15 vision at 35, despite probably averaging over 8 hours a day staring at computer screens for over 2/3 of my life... But maybe I'd have superhuman vision otherwise?
I spent 10 hours a day on computers when I wasn't at school during middle school. Started at the end of primary school and continued until now. I pass the letter-reading tests at the GP when I'm not too tired, so I think I have pretty good vision.
Maybe that's because I didn't always have a computer nearby and had to spend time outside too as a kid.
There are also theories that the cause and effect are actually in the other direction: kids with poor distance vision are more likely to spend time reading and studying rather than be outside playing sports.
Gross generalization, but my suspicion is that it’s not the all day staring at computer (that’s most adults these days) but also many CS types spend their free time in front of a screen as well…
I got my first computer at 10, was 20/40 vision at 16 and am probably around 20/80 right not.
Honestly I'm glad that I am now that I'm in my 40s. Without glasses or contacts, I can read something right up against my nose. Makes it so much easier to work on electronics and other small items - I just take my glasses off and I see up close perfectly well.
The different usage of words and their meanings in English is interesting and makes me think this weird miscommunication is why we have so many arguments. In my everyday, the article would be referring to nearsightedness, short sighted would be when someone doesn’t think through all the possible things, lacking foresight. By definition it’s both but in every day use it’s not.
That's the article I was expecting, also. Lack of foresight these days is a serious problem - with the mis-education current in the US, the younger cohorts are losing the historical perspective developed so painfully over the last four thousand years. What to do is not so important as what not to do.
I'm in the same boat; I was expecting to read an article about managers/CEOs taking short-sighted decisions.
To be noted, I'm French, English is not my native language so when I realized my mistake I thought that was because in the case of this title it was obvious that it is about eyes but I just didn't knew how to catch the clues.
In everyday use in this part of the world you never hear the word near-sighted. In Australia and I think a lot of other British English countries, short-sighted is the plain English term for myopic. (But the thing is most of us know that the US uses the other term)
Not just with light, spending more time indoors means kids don't have to focus their eyes on longer distances these days. There would be a correlation between the amount of time spent indoors during the formative years and the chances of becoming myopic in the future.
Agreed. My wife had no electricity for her child life, but is nearsighted... probably from reading books all the time as a kid. I don't believe that light has anything to do with it.
It’s not related to light, it’s related to over focusing, especially in peripheral vision. Keeping things close to the face keeps things in focus, making the eye thinking it’s over focused, so it grows longer to defocus. It’s called emmetropization and it’s how the eye grows.
For several decades it has been known that myopia (nearsightedness) and intelligence are correlated[1][2]. Initially it was speculated that reading caused nearsightedness, and through that higher intelligence. There is probably some truth to that.
But with modern DNA sequencing techniques researches has found genes that seem to affect both[3][4].
The hypothesis is that one (or a set of) genes affects both eye size growth (myopia is often caused by the eye being "too long") and neocortical size (associated with intelligence).
Although this probably won't surprise anyone in this research field, I recently read about it -- with my non-nearsighted eyes :) -- and found it interesting. So I wanted to share, since it's somewhat related to this topic.
The issue with these types of studies though is that there's no way to really parse out correlation vs causation, either between these two variables or with social factors at large. Especially in this case there was no molecular work done to validate the hits or establish causal pleiotropic effects. The authors are incentivized to tell a story but as readers I think we can be a little more skeptical and evaluate the likelihood of those kinds of claims (there's positive selection on genes that both increase "intelligence" and alter eye shape) versus like, environmental and social factors induce a correlation between needing glasses and reading...
I thought the increase in nearsightedness originated in kids not playing outside as much (and thereby not focusing their eyes over longer distances) resulting in eyesight that's more attuned to shorter distances.
Their summary seems to suggest that the biggest factor is exposure to daylight. So then even reading outside ought theoretically protect against nearsightedness.
> People, and children especially, who spend more time doing physical exercise and outdoor play have lower rates of myopia,[30][29][31][32][33] suggesting the increased magnitude and complexity of the visual stimuli encountered during these types of activities decrease myopic progression. There is preliminary evidence that the protective effect of outdoor activities on the development of myopia is due, at least in part, to the effect of long hours of exposure to daylight on the production and the release of retinal dopamine.
> The near work hypothesis, also referred to as the "use-abuse theory" states that spending time involved in near work strains the intraocular and extraocular muscles. Some studies support the hypothesis, while other studies do not.[3] While an association is present, it is not clearly causal.[3]
This is what I meant. The GP comment included "and thereby not focusing their eyes over longer distances", which I interpreted to be in contrast to spending time indoors and looking at things close to you. So it's not that things far from you are protective, but specifically variety seems to be. So I think we mostly agree.
Can’t find it now, but there is also a comparative development study showing myopia and indoor electrification setting in together in different countries. Though that paper speculated blue light content, with a developing eye hard coded to “tune” its length on the assumption of sunlight.
I've read that the amount of natural light is important, and that the light inside buildings and houses is not sufficient. Children should spend more hours outside.
This should be easy to answer: we are not smarter in the recent decades (the opposite is likely true due to the leaded petrol). The natural selection for smartness is too weak in humans (it does not take much brain to reproduce nowadays).
The hypothesis in TFA is much more likely (regular exposure to bright daylight in children)
(Though because IQ is standardized around a mean of 100, it's probably more accurate to say that the IQ of people in the past has retroactively gotten lower)
The flynn effect is well documented. The negative effect of leaded gas on intelligence just means that average IQ "should" have been raising even more throughout the 20th century.
I heard somewhere that the speculation was that the cerebral cortex is physically next to your eyes, so a big brain stunts your eyes... anyone know if there was any truth to that?
The last study says “myopic children regardless of their IQ gain better school achievement”. This makes me think the difference is cultural vs genetic.
Wearing glasses certainly shaped my hobbies - more reading and computer time. On top of that, being nearsighted (pre glasses) made it hard to catch a ball, so less time spent doing sports.
Number 3 is interesting , it’s a twin study. I still have to read more, but their best fit model has the same p value as storks delivering babies, if that helps you.
Edit: I do wonder how some recent studies on myopia fit in with these other findings:
“ The decrease in heritability and the increased myopia prevalence in our sample may not be related to the age of the sample, but with the year of birth and the changes in the environment in what these subjects developed during the last two decades. Due to the higher academic skills of our study population, it can be considered that they have been highly exposed to one of the myopia risks factors related to abuse of near work and large periods exposed to low luminance environments11,19,20. Many studies showed an increasing trend of myopia incidence as we are approaching the era of modern industrialization along with increasing education level3,11,19,20. The older twin sample34 had in average a lower education level and possibly less prolonged near task. This may signify the connection of these trends with our obtained results with greater environmental influence on refractive error variance among studied millennials. The change in myopia prevalence is happening across the last few decades, where the increased offset cannot be explained by a change on genetic factors, as genetic evolution cannot take place in such short time span. On the other hand, less than 10% of the variance of refraction could be accounted for Genome-wide studies, where studies have identified, so far, more than 150 single nucleotide polymorphisms (SNPs) associated with myopia44. Alternatively, the high heritability of refractive error observed in most of the twin studies can be a result of heritability overestimation by the classical twin study model. From any perspective, we must understand that heritability is the combined result of genotype and environment on a certain phenotypic trait. Hence, it appears that the sudden increase in myopia prevalence is a result of higher interaction with the environment.”
Well obviously, but that is not the counterpoint to what I was saying at all. If you see science that you don’t “believe” is true, then you need to do science to show us it isn’t true before speaking out about it. Maybe not everywhere, but at least here on HN people still prefer to take reason and proof over anecdotal stories from your undocumented and limited experiences.
Please note that I don’t mean to say your anecdotal experiences can’t be interesting, just that they can’t be used as science until you do the work to actually prove that they aren’t just your experiences.
Well if scientific paper contradicts the observable experiences from the real world, then obviously something went wrong during the experiment.
And you still believe in this paper because you didn't reproduce it yourself or you didn't see it being reproduced step-by-step in real life, you rely on this scientist who conducted the experiment reporting it legitimately and other scientists involved in peer review process to have actually read the paper and verified it through reproduction (which isn't all too common in academia btw.)
Plenty of people do blindly believe it (hence the catchphrase "believe science"). Best to combine your two statements: you don't have to "blindly believe" in it.
This. I realized that it wasn’t necessarily genetic I may just have my monitor too close. I swapped it for a 70inch 4k monitor/tv six feet away and my eyesight improved by a quarter point over the next year.
I noticed my eyesight gets better after many hours outside not looking at any screen. And worsen after many hours in front of a screen. Is there a name for that?
Your eye is a muscle, focusing only at close range keeps the range of motion tight. Just like your back and neck might get stiff sitting all day.
Sunlight means smaller pupil, wider depth of field, just like a camera.
(My speculation) More light gives you brain more information to clean up or upscale a blurry image. This effect even seems to last when you leave sunlight, for awhile. It's like I fine tuned my neurons to prioritize blur reduction, and it takes awhile for them to fall back into normal processing. If this is true, my guess is that I might be trading off contrast or color details for sharpness.
have you verified that it actually gets better and that you're not just getting used to it?
I used to think the same thing when I just tried not wearing glasses for a while. I could swear that it was awful at first but over time my no-glases eyesight improved tremendously. I then did a really simple distance reading test and it was obvious that it didn't improve at all and the effect was imagined.
>Sedentary, white-collar jobs are less arduous (and less lethal) than manual work. They also promote obesity and heart disease.
I'm always baffled by the dismissive wave of the "activity level causes obesity and heart disease" trope--because it's mostly wrong. The first world diet is the primary cause of obesity and heart disease, and it's well-proven. Starch and sugar, processed foods, a diet primarily consisting of carbohydrates. Diet is the driver, not activity level.
Seeing this is the economist, I thought they meant shortsightedness of our business and industry leaders. Was a bit dissapointed that instead of much needed self-reflection, the topic is far more pedestrian.
I'm hopeful that the shift to VR from PC gaming and perhaps also office productivity will help with myopia. Might seem counter-intuitive given the VR lens is next to the eye but focus in VR is in the distance. Even productivity in VR is usually done on huge screens further away from the user than traditions pc screens.
Wearing contact lenses with VR is a huge difference compared to without. So I think there is some potential in what you are saying. There could even be room for eye training apps etc.
I wonder if indoor lighting at the appropriate temperature would help prevent this?
In the UK we don't get a lot of sunlight in the winter months. It would be nice to know that we can turn on a "sun lamp" or whatever for homework time to help alleviate the issues.
There's an increasing body of good evidence that bright indoor conditions also lift mood and improve productivity, often quite noticeably.
Since the pandemic and work-from-home, I've been working in a home office where an entire wall is a glass door leading to the balcony, floor to ceiling. I let the light stream in, and it's basically daylight inside. I had to get a brighter monitor (600 nit OLED), but now I just can't picture myself going back to work in a gloomy cubicle farm. The grey, dim light would just depress me.
There's a few hobbyists using large LED or OLED panels to achieve the same kind of lighting effect as overhead sunlight. Because of the higher efficiency, it's now possible to do this without an extravagant power bill or excessive heat. This makes the most sense is in places closer to the arctic, where winters are long, dark, and cold. So in effect, the "wasted" heat energy of the lighting simply contributes to heating the workplace or home.
Here on YC News more than a few people have suggested that this might be a nice startup to work on: "indoor sunlight" products and installation services can start small, but can scale up! You can also imagine combo products, such as solar-power + batteries + bright lighting panels.
There's an amazing youtuber/creator I've been following for a while and he does exactly this. Goes into the science of what it takes, and the results are really stunning. I'd love to give something like this a try, just need time.
Also there was a breakthrough a while ago with LED ceiling lights that mimic natural sun. I haven't heard much since their release, so I'm sure cost is still a major issue for these sadly.
These techniques would be very useful in the three darkest months in Scandinavia, where the sun is down both when you leave and return from work, and generally behind clouds otherwise.
Me, I’ll climb the floors of the office and stand in a windowed stairwell with the sun in my eyes for ten minutes after lunch every day, when the weather’s good, but that’s being kind of anal about it.
The sarcastic self deprecating English in me wanted to say “well at least 4 days”, but we’ve had a pretty good run this year. We are up to at least 6 (lol, still can’t make myself say you are wrong..)
Where I live we have sun 18-22 hours a day in summer and maybe 4 hours in the winter - the sun doesn't even go halfway up before going down again on those days.
Unfortunately me and my partner both have our families here so moving is not an option. Being able to see decently strong light in December without having to travel would be worth a lot to me.
For the visible portion, that's around 25-50 W/m², so around double that for current LEDs. The question becomes: at what illumination do we start to get a significant effect?
Long answer, you'll need to really jack up the power consumption. Replicating a thing that in itself an energy source needs waaaay more than just a 60W light bulb.
> 60W would be some 10 LED lights that each are 100W equivalents to old glow lights. That would probably already do the trick in a small room.
Not really, daylight is not 10 times but much more brighter than a 100w incandescent lamp, such illumination (e.g. it has certain uses to help seasonal depression) exists but it's very bright compared to normal indoors lighting.
The old 100w lamps were ~1600 lumens; outdoors daylight is something like 10k lumens/square meter in shade (direct sunlight would be another order of magnitude more), and an appropriate number for the surfaces of a small room would be in the ballpark of 100 of such LEDs so 600w of electricity.
Yes, I do. Where I live, winters are long, so none of the heat is wasted. But that aside, the real reason is the quality of the light. Spectra! Incandescent lighting is a black body radiator basically, so you will have a full spectra curve even if it is weighted toward the red side. The downside of LEDs (and the CCFLs that preceded them) is that they only have a few narrow peaks in the spectra, R G B at differing heights and the rest of it is low. This is why colour rendition generally looks poor, and even worse, they flicker! Because we live in a society that wants everything as cheap as possible, the LEDs generally flicker at 60 or 120 Hz, sometimes higher. This causes a strobing effect, etc. This can be avoided by using DC current, but who uses that? CCFLs used electronic ballasts with much higher rates but they're not on the market anymore. Incandescents have a small degree of flicker too, but it's basically non-existent because as black-body radiators they continue glowing until the next pulse arrives.. LEDs are not like that, they are instant on-off, and their "dimming" trick is usually pulse-width-modulation where they're still fully light, but their duty cycle is spaced further apart, you think it is dimmer but it is not.
Yes! I'm experimenting with this right now with a very bright, color temp adjustable, high-CRI photography lamp, and the difference is, well, night and day. There are several good posts out there on the subject.
Pretty sure in the recent times COVID has worsened this. I do exercise often these days. But its nothing like the morning workout, lunch time socialising, and tea time walks with colleagues before COVID.
These days apart from the workout in the morning I get no outdoor activity, its just staring at every decreasing(sizes of) screens. I'm showing early symptoms of Shortsightedness. Several other colleagues tell me the same, there's also additional problem of people getting obese staying at home.
Though schools have opened. Last two years were equally worse for kids, no play, classes on smartphones and laptops.
Why can we have 2-lense glasses that move the focus to infinity?
ELI5: In opticals, “rays” coming from a near object (=mobile phone) are angled, while rays coming from afar (=end of a landscape) are parallel. The job of pupils is to bend the rays from the focal point ahead to the focal point on the receptors in the eye. The eye is a rest when looking afar, because rays come parallel, and thus there isn’t much to do. The eye is strained when trying to focus one something closer.
I’ve always wondered why we all had that UV filter on screens and never took care of making the rays from the computer screen parallel, using a lense.
You and I and a few others around the web all have had this idea of making screens look farther away, by changing focus with positive lenses and and binocular convergence using prisms. I actually wrote this comment with the math for determining the required prescription (since you can simply order them online) just a month ago.[1] I then found that the concept isn't uncommon when I discovered an older comment with the same idea, which I've misplaced, but a search turns up another thread revealing that this already exists as a product marketed for gaming.[2]
Good info on refractive error there, though I don't see much on prism lenses used for this purpose. While searching, I did discover this book, the Myopia Manual, which they're hosting a copy of. It looks quite thorough and does have a chapter on using prisms to match vergence with accommodation in plus lenses. The book also has its own site http://www.myopia-manual.de/
I also found an older myopia submission where a comment links several related sites.[1] frauenfeldclinic.com now redirects to endmyopia.org; archive.org confirms that the old domain was the same site, but oddly the new domain has an exclusion applied. As one reply noted, myopia.org really is an excellent display of the Time Cube design language.[2]
Around 1995 I wrote a DirectDraw text-editor that would render two images and force you to defocus your eyes like the op-art-3d puzzles: making the viewer have to focus far away. It worked for images but not for reading small text.
You can do that cheaply by picking up a pair of reading glasses, or glasses with lower power if you are already nearsighted. Roughly, infinity will be at 1/diopters in meters, so +0.5 glasses will make 2m away at infinity, +1.0 at 1m, and so on, and similarly if you are at -3, -2.5 will make 2m infinity, etc. It's not exact because they are not thin lenses and there is a separation between lens and eye, but it should be pretty close.
I've been using one less diopter correction for a while most of the time, with an additional pair of glasses with the full prescription for driving. Not sure if it does anything or my nearsightedness just naturally stopped progressing though, but since it's working and not bothering me I have no interest in finding out.
How would it work? Where would you put the two lenses? Consider:
- You can't really have two lenses cemented together. That'll correct for chromatic aberration but, other than that, the lenses would behave as one (except for deviations from thin lens approx.)
- You can't have glasses mounting two lenses "d" apart for two reasons. 1) Having parallel lenses would terribly uncomfortable, heavy, and awkward 2) More importantly your eye and the two lenses would never be aligned (as soon as you move your focus away from the one spot the glasses were aligned for, the optical system performance would collapse)
- The best you could do, then, is contact lenses + eyeglasses. But then you have all the bother of wearing glasses and eyeglasses. Also, it's not obvious to me it would work since the contact lenses are in contact with your cornea, the pair behaving like a single lens.
I think GP is mistaken about two physical lenses being needed (until it's the future and we're all wearing expensive smart glasses, in which case you do want an additional interchangeable lens for this purpose). When designing the system, it can be thought of as a lens that corrects for refractive error of the relaxed eye (moving the eye's far point to infinity) stacked on top of another lens that makes light coming from an object parallel (producing an image of the object at infinity for the first lens and eye to receive); to implement it, you only need one lens with the combined power of the two.
I think you get the effect you desire by wearing glasses with + when in front of a computer.
anecdote: i started with -0.5 (10-15 years ago), per ophthalmologist "advice" wore glasses all the time (including computer), got to -1.75. then one summer spent some time without any glasses (just because i wanted to use the sunglasses) and at the end of the summer the vision went back to -1.50. This got me thinking that wearing glasses all the time is not that good. 4 months ago started to experiment, no glasses all the time and +0.5 when in front of the computer. Started with -1.25, and now I am at -0.50/-0.75 ... take it as you want.
Assuming that it’s technically practical, the results would be very unsettling: the phone screen would look like a window with the content “behind “ the window, very far away.
I doubt that effect would be very strong as the effect of a magic eye massively dominates any feeling we have to notice that our eyes aren't having to do as much of whatever you'd call this lensing work.
I usually don't agree with The Economist but I agree with them on this one, people spend too much time indoor and that's why there is an epidemic of shortsightedness.
I would actually call it pandemic because it is affecting all developed countries because majority of their workforce works indoor and then goes home or to the gym....again indoor environment.
I heard it said that it's lack of UV that does the damage, glass filters out UV. Sounds like it might be a resolvable problem without having kids take class outdoor.
"Some of the loci identified include those involved in dopamine and light processing. These genetic findings provide further support for mechanisms of myopia development involving light exposure, defocus and contrast.
Despite these important findings informing potential genetic locations and mechanisms of myopia development, these studies have identified less than 5% of the variation in refractive error due to genetic variants.42 Clearly, the dramatic rise in myopia cannot be due to genetics alone, but is likely due to a combination of both genetic susceptibility and increased environmental triggers."
Thanks, but the contents of your linked PDF, which is just plaintext, no images, is different from the Archive copy of the article shared up-thread here https://news.ycombinator.com/item?id=31712453
Did the Economist show you a different article with the same title due to your location?
When I was a kid, we had a "no TV when the sun is up" rule. That included computer screens, which were literally TVs when I was a kid. Of course I violated that rule when my parents weren't looking, but for the most part I spent a lot of time playing outside, especially in summer.
This is of course anecdotal, but I'm 45 and still don't need glasses.
I'm trying to do the same with my kids, but sometimes it's just too easy to hand them an iPad when I want to get something done....
When I was a kid we didn't have a computer. Home computers didn't exist until I was in my teens. We had one 12-inch black-and-white TV that received four channels when the rabbit ears were set up properly. I spent a lot of time outdoors.
This is of course anecdotal, but I have needed glasses since before fifth grade.
(I got my first pair of glasses in fifth grade, but in retrospect it was clear that I needed them much earlier. I can still vividly remember the first I ever tried on my new glasses and being astounded at the level of visual detail that existed in the world. Stars! Leaves on trees! Wow! I had no idea.)
When I was a kid, we didn't have TV, and computers had just been invented.
But, I read a lot, often in bed at close distance, and I was astigmatic and near-sighted when I was young. Now, I'm mostly just astigmatic and presbyoptic.
I've written about this before, but it bears repeating. However good your vision is when you're young, it will change as you get older.
Most people become more farsighted as they age. Typically it starts when you are around 40 and changes rapidly for the next decade. After that it tends to settle down.
More importantly, the lenses in your eyes become more rigid, losing their ability to focus at different distances.
When I was younger, one eye was a bit nearsighted and the other a bit farsighted. This allowed me to get away without glasses longer than I should have. Even if I wasn't seeing clearly with both eyes, I could see at most distances with one eye.
As my eyes' focus distance lengthened, my nearsighted eye attained close to normal vision, and my farsighted eye was focused past infinity. Not good.
When I got my first pair of prescription single vision computer glasses, it was life-changing. Now I could see my laptop screen perfectly. I told my optometrist I wanted something like single vision reading glasses, but adjusted for the distance to my laptop screen, about 20", unlike the typical 16" focus distance of a reading prescription.
In fact, this started to make me fussy about using high-DPI displays (~200 DPI) instead of the low-DPI displays (~100 DPI) I'd previously used. On a low-DPI display I could see the pixels!
It does mean that when I use external monitors with the laptop, I need to have them also at this 20" distance. So to augment the laptop screen, I have a 24" 4K monitor in landscape mode immediately above it, and a second 24" 4K monitor in portrait mode to the left.
Both of the external monitors are at about the same 20" distance from my eyes, and each of the three displays is angled differently so the center of the monitor is aligned with my vision: the laptop display at a typical laptop angle, the one above it closer to vertical (but still tilted a bit), and the one on the left at an in-between angle. The bottom of this monitor is about a half inch above my desk, just enough room to let cables run under it.
This is a fairly glorious setup. All three displays are in focus for me, and the portrait display is great for reading documentation, especially PDF files that are so awkward on a landscape display.
The key to this is the single vision glasses. I have seen so many people try to use progressive lenses with their computers, and they are always craning their neck back so they can see through the lower part of the lens that has a closer focus distance. Single vision lenses let everything be in focus at once, especially with the portrait mode monitor.
Another key is that the computer glasses should have a fairly tall profile, not the truncated rectangular lenses that are so popular. This greatly improves the field of view.
On my last visit to the optometrist they suggested lenses with a blue light filter. I said no thanks on that. Sometimes I do photo editing, and the blue light filter shifts everything to a warmer color. The way I solve the problem of too much blue light is that I simply don't turn my monitor brightness up so high. It is set so a white background is about the same brightness as a piece of white paper in the same lighting.
I also have progressive glasses that I use for everything else when I'm not at the computer. These have magnetic clip-on sunglasses, which are pretty great. Indoors I can leave the sunglasses off and just use the progressives on their own. Because I wear aloha shirts with a pocket, I can keep the sunglass lenses in my pocket and I hardly know they are there. When I step outside or go driving, I just snap on the magnetic clip-ons and I'm good to go.
The frames with magnetic clip-ons are a bit uncommon these days, but they are well worth finding.
If anyone is curious I can look up the brand and exact model number for both the round single vision and the progressives I'm using.
While I am all for the idea that we need to have more sunlight indoors, I am not at all convinced that's the cause for the condition. TV watching wasn't big when I was a kid, and I didn't have the patience for reading, yet I've got it.
So yeah. I am sure prolonged focusing contributes a lot but not sure it's the main cause.
I feel like this has always been a rather obvious thing...for at least what nearly a century or more? The whole trope of glasses are for nerds. Kids who spend time reading a ton are nearsighted. I understood this in elementary school, when the only kids with glasses were the smart ones. (I hated reading, and did not wear glasses, so was not a 'smart one').
I became nearsighted not long after getting a home computer, for similar reasons. My father, an avid farmer and naturist, is farsighted. It seems pretty obvious your eyes adjust to whatever you spend all day looking at.
That all said, is it bad? Mine was cured with a rather cheap PRK procedure...and I sure wouldn't give up all I've learned for perfect natural eyesight.
As another single data point, I started using a Commodore 64 when I was 5 years old, and have been besotted with computers ever since.
35 years on, and my eyesight somehow still remains fine - I'm slightly short sighted in one eye, slightly long sighted in the other (how does that even happen?!), but opticians always say I don't need glasses.
I think you're right - there are simply way too many factors to control for, and statistics is the way.
It was kind of common knowledge that something related to being a nerd was causing myopia, but I'd say most people assumed that the culprits were things like reading and screens, rather than being indoors.
I often thought that glasses and people who do a lot of reading etc was a side effect rather than a cause - i.e. that people who read more noticed they needed glasses and we're happy to wear them, but kids who would rather do sports perhaps didn't notice so much and/or were less inclined to wear glasses when playing cricket or whatever
I replied elsewhere...I disagree that light type is the culprit. If so, why do people in areas without electricity become myopic? That strongly feels like correlation rather than causation at its finest.
My brother and I were kids with mostly similar habits. We spent a lot playing outside, but he loved reading his Goosebump books, while I mainly watched TV at a distance. He needed glasses as a kid, and I didn't until we got a computer in my teen years. It completely feels like it's a focusing distance issue.
The reasoning is supposed to be statistical, so your counterpoint "why do people in areas without electricity become myopic" doesn't even make sense. A proper counterpoint would be "people in areas without electricity have the same chance of being myopic as people in areas with electricity", and well, data seems pretty clear they don't.
Fair point. Would another fair avenue to potentially counterpoint be to ask why countries with less light for long periods, such as Nordic countries, or areas where people spend months at a time indoors like frigid areas, are not more nearsighted than fairweather areas like Singapore?
Unrelated, I'm wondering if there is some method to tell. The general fact is, people indoors tend to be focusing on things close by. And vice versa outside. So it feels impossible to conclude without controlling for the other. Can we find people who read or smartphone for hours on end outdoors? Or people indoors who don't do those things?
You disagree with science based on a 'feeling'. Myopia in children is what we're talking about, and sunlight exposure is not the only factor. Similarly, having similar habits doesn't mean you will get the same result.
I get your point, I'm not going to tell you I'm right.
But realize the article says 'researchers think' and 'evidence suggests.' Far from proven science. If it's more firmly established, I'll gladly admit I'm wrong.
But that's not happens, it's not that your eyes get adjusted to only seeing things closer, rather they don't develop well unless they are exposed to sunlight. Which just goes to prove it hasn't really been obvious all along.
If you don't read, you don't need glasses. If you don't use glasses and need them, you end up not reading and end up having trouble in school - being treated as dumb.
Myopia has been an epidemic for many years now. And the future prospects look grim. Fortunately, there are research groups tackling this issue hoping to develop some gene-therapy approach.
I can't believe you're serious. I wear glasses and there's nothing wrong with me. Last thing I want is to live in a world where I'm pressured to be genetically engineered for having the wrong kind of eyes.
I wear glasses and there's nothing wrong with me at the moment either, and I hope it keeps being that way, but the augmented risks mentioned by the GP are real and well-attested.
In fact, many ophtalmologists consider LASIK and their ilk to be cosmetic surgery, because it gets you rid of the glasses, but not of all the other consequences of myopia.
If there’s nothing wrong with you, why are you wearing glasses? I wear hearing aids because my hearing is flawed. I would be ecstatic if there was a genetic solution.
I'm sorry to hear about your hearing. From what I've heard, hearing aids help but they are not a satisfactory solution. So if you still feel something is wrong, then the way you feel is what matters.
There's nothing wrong with my vision because I wear glasses. I like my glasses. I consider glasses to be a satisfactory technology that solves the problem I used to have before I got them. I see myself as one with the technologies I use. If someone thinks I should adopt the GE technology instead of the optical glassware technology, then fine, but no one has the right to tell me I have a problem.
Ideally what I'd want are glasses that let me see the things normal people can't see, like electromagnetic radiation other than the narrow part of the spectrum for visible light, such as infrared, gamma rays, and hidden colors, etc. Superhuman vision would be real progress imho and a whole lot less creepy than what's being proposed here.
They are called “corrective lenses” because they are correcting your flawed vision. You have a problem you address with glasses. It’s no different than any other medical technology to address a life altering flaw.
You can be happy with the solution, but there is still something wrong with your eyes. Someone offering a solution that actually fixes your eyes shouldn’t be offensive and you most certainly shouldn’t be discouraging it. It’s like someone getting in a huff about a diabetes cure because they see their insulin needle as a part of themself.
There is an advantage to being able to take them off. Crying babies, dogs barking, lawnmowers, etc. go bye-bye. Your body still feels the vibrations which of course is biologically stressful (e.g. constant vehicular traffic), but psychologically it is a calmer state.
That said, there may be a drug to help restore some of it in a few years for some people, but I won't be first in line for it, because I'd like to know more about negative outcomes in a large population.. tinnitus risk, etc.
I have around -10 dioptres in both eyes, like my father. I am also amblyopic. It is a minor inconvenience for me right now, but the risks for serious problems in the future are real.
The problem, if I understand correctly, is that myopia correlates well with eyeball elongation, which puts stress on the retina, thus sharply increasing the risk of macular degeneration and retinal detachment as you get older. Other complications are also more likely to occur.
I was only vaguely aware of this until recently but I am a bit worried now and going to a doctor soon to asses the situation and manage the risks if possible.
Not to scare you or anything but to just reinforce the fact that you should incorporate regular retinal exams. My daughter is also around -10 and in a recent eye exam they did the retinal imaging thing (that i always thought was just an upsell scam). Well they found what they thought was retinoschisis. They referred her to a retina center (which of course took nearly a month).
At that exam they found that her left eye had substantial retinal detachment and scheduled her for a scleral buckle procedure the following Tuesday to avoid any further progression. Aside from seeing some sparks every now and then there were no symptoms. Ocular migraines run on both sides of the family so she wasn't too worried about it.
You can get glaucoma later in life. I was diagnosed in my mid-40s, now I have to take drops for the rest of my life. And still might go blind. Some people with open-angle glaucoma don't even know they have it, which is why it is referred to as "the silent thief of sight". I'd definitely take a genetic cure for this if one existed.
There might be nothing wrong with you now, but there is no guarantee it will stay that way.
If you wear glasses for nearsightedness and your doctor hasn't talked to you about your high risk of things like floaters, retinal detachment, or glaucoma, your nearsightedness isn't very severe.
Good for you that your vision is barely a real problem. For people who have a real, genetically heritable risk of going blind well before they even reach old age, that kind of research is very much of interest.
Because glasses suck, and we don't wanna condemn future generations to wear them if they don't have to (and they still can if they so choose, of course).
Everything in nature is fractal-shaped, while most things in our artificial environments are made of flat surfaces. If you think of light as a kind of "food" for the eyes, we are effectively eating junk food all day every day.
Well, it's The Economist, very evident in the title line (it would be news if they removed the protection). And, incidentally but importantly, it uses a "payfence", not really a paywall.
Most cases of myopia (nearsightness), involving progressively worsening vision, are largely due to inaccurate lens prescriptions and bad habits.
An optometrist or optician will have you sit with your head in the phoropter asking "better/worse" while flipping lenses - pretty much a binary search type of approach. But this is often done hastily and results in inaccurate prescriptions.
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Unfortunately, inaccurate scripts are often inflicted upon children which as I will describe later, compounds into worsening vision over time, with the opticians/optometrists prescribing higher and higher power lenses that are only solving an issue that is created by the previous history of inaccuracy! Telltale signs of inaccurate scripts include:
- minor corrections
Eyes are not static objects and vision actually does vary from month to month, day to day, lighting conditions, blood pressure, etc. If a correction is minor, it's almost always unecessary and harmful.
- slightly different prescriptions for left (OS) and right (OR) eyes.
99.9% of folks have equivalent vision in both eyes. Like I said above, if a difference is minor, a correction would almost always be harmful.
- minor cylinder corrections (astigmatism.)
Astigmatism is extremely rare and when it does occur it's almost never minor. These corrections are especially egregious as they cause distortion compensation.
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So why do eye professionals commit these cardinal acts of eye destruction upon their patients? Well we already discussed hastyness but that is clearly a vice that is going to result in bad outcomes in any profession.
What else? Well, eye professionals are taught to seek out as perfectly sharp an image as possible, and then back off the power a bit to reduce the possibility of eyestrain, headache, and dizziness. Some professionals don't even back off the power though..
In order to accomplish this task of perfect sharp vision, they add all of these minor corrections. When these ill-fitting lenses are worn for months on end, the body has a somatic response. The eyeballs elongate, which pushes the focal plane back, causing further myopia. [1]
The patient goes back to the eye doctor and now receives an even more incorrect script based on the transient state their eyes are in, induced by a cascading patterned history of harmful scripts.
In the worst case, the eye doctor recommends laser eye surgery which shaves the corneal lens of your eye into an artificial lens. Essentially, they carve your current harmful prescription straight into your eyeball. And then guess what happens? The eyeball shortens and often, the patients vision becomes progressively worse again. It can take months, but it does happen. [2] And now the fix that they recommend? More laser eye surgery. It's barbaric.
So please, do not get eye surgery before trying what I recommend below. Surgery on the cornea is advertised as non invasive but it can cause life long issues such as chronic dry eye. Please try to assess whether your vision is actually bad, or just a transient state due to a long history of bad prescriptions and poor habits.
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How do you break the cycle and restore your vision?
1) First, look at your current script. How asymmetric is it? How small are the cylinder values, if any?
Lower the scripts power and make the prescription symmetric. Remove the minor cylinder values. So for example, if you had -3.6 and -3.4 with some small astigmatism corrections, just ask for a script for -3.4 SPH in both eyes.
2) Make sure the pupillary distance is correct - eye professionals are notorious for fucking this up because the PD needs be to custom set for the frame the lenses will be going in, otherwise you'll have lenses with a focal center that is not aligned with the center of your eyeball. This causes distortion and uneven focus, causing eye strain and worsening vision.
3) Aspheric lenses - buy good lenses like Seiko double aspherics - just like cinema or photo lenses cost a lot of money because they reduce abberation and edge distortion, your eyes benefit from the same technology. Bottom dollar spherical lenses are okay, but strain is not healthy for eyes, and a good $300 set of Seiko transition lenses with coatings can last 10+ years. It's worth your eye health.
4) Have multiple pairs of spectacles. Use the weakest usable one (or no specs) depending on the task you are doing. For instance, I'm on my phone in bed, so I am not using any glasses. This will improve your vision over time. You can slowly reduce the power of your scripts if you care about it. I went from -4.75 to -3.5 and I'm happy with what I'm at, so I don't spend any effort trying to lower any further. But if you have the money, the time, and the will, you can get to -1.X territory through judicious use of a set of activity appropriate lenses.
Lastly, buy your own frame, buy your own pupilary distance tools, buy your own trial lens kit and trial frame like the Oculus UB6. Take time and figure out the right prescription for yourself without it being rushed. Test it and have it remade if the center of focus of the lenses is not at the center of your eyes. PD is integral!
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An eye professional who cares and understands these things CAN help and even properly measure these values but they are rare. Sometimes if you want something done right, you kind of have to do it yourself. Or at the very least, guide or give your demands. After all, you are the paying customer.
Hope this helps others break the cycle of worsening vision. If anyone has any question, feel free to reach out.
I read the title and immediately agreed, but i had misinterpreted "short-sightedness" as the inability to consider the long-term effects of our choices and habits, at least to the effect of making positive changes, rather than the ocular deficiency.
Short-sighted, near-sighted, and myopic mean the same thing. Both short-sighted and myopic are often used figuratively (to mean acting on short-term interests without considering long-term effects) while near-sighted seldom is.
> I read the title and immediately agreed, but i had misinterpreted "short-sightedness" as the inability to consider the long-term effects of our choices and habits
I had the exact same reaction, and was genuinely surprised when I clicked through.
The Economist has another article this week that's basically about that: https://www.economist.com/united-states/2022/06/09/miamis-su.... It's about Miami and how local, county, State, and Federal governments are just totally incapable of planning long term for climate change.
I didn’t realize the evidence is strong that daylight keeps kids from becoming near-sighted. Making young kids study all the time is killing their eyesight!
Yeah, I hadn’t heard about this ”daylight” thing either. I’ve been nearsighted since I was a kid, and back then people said I got it because I read to much, focusing on things too close to my face. I thought that was a pretty fair trade-off, since I liked reading, and didn’t particularly mind wearing glasses.
This sunlight thing makes a lot of sense though. I kept hearing proposals during the pandemic about holding classes outside if the weather allowed for it. Might not be such a terrible idea in climates where it’s suitable.
My daughter’s primary school teacher recently got a “beach teaching” qualification and she now has one school day a week on the beach, rain or shine. I was really pleased about that anyway as the school doesn’t have a lot of outdoor space for the kids to run around, but this gives me even more reason to be happy.
I know what you mean - I also had a bit of a similar reaction at first - but as I understand it's how to run lessons on a beach without classroom teaching materials to hand, how to use things on the beach in the context of certain subjects etc. Also, I said "qualification" which probably makes it sound grander than it is - she just went on a 3 or 4 day course.
You should've stopped at the scoff. Someone qualified to handle children in a classroom and in field trips is already qualified to take them to a beach.
I think you may be misunderstanding, which is perhaps understandable given that I didn't unpack what it meant - see my sibling comment. But scoffing without asking for more information isn't a great strategy for learning.
I grew up in a beach town and gone to the beach in kindergarten all the time with the school without any special certifications. In the event kids go into the water there's always a lifeguard on duty already so otherwise it's the same as any other school outing, I'm not sure what the difference would be from leading a group of children in a city walk for example which to me looks way more dangerous.
I was told reading was my problem too...except I was only nearsighted in one eye. My right eye couldn't focus clearly past the length of my arm, but my left one had no trouble at all. For years, I wore a plain lens for the left eye, and when I was old enough, switched to wearing only one contact lens.
They confirmed it wasn't that I was reading only with my right eye, and it's obviously not like my eyes got different amounts of sunlight, given that they go everywhere together, so I've always been suspicious that that was a lazy answer.
What ever the name says, it isn't paper white. Actually, I think there is little difference, the difference is the light, which makes the PaperWhite look whiter in normal light and enables reading in dim conditions.
I think (weakly) the nearsightedness issue is indeed from not exercising focusing rather than sunlight.
But apparently there is an issue where mothers with low vitamin D in Scandinavia (especially immigrants from sunnier places) are more likely to have autistic children.
Anecdote, I started fidgeting by varying eye focus and depth - can't get forced to sit still if your fidgeting is barely perceptible - at a very young age and have the best range of accomodation of anyone I know. Can also easily perceive chromatic aberration/my eyes needing a different focus setting for different wavelengths.
I'd love to know if some sort of focus training exercises for eyes starting as children would help everyone.
I bet not long before that the old folks were complaining about the kids watching too much TV, reading too many comics, or playing too much backgammon.
That doesn't certainly help, but there was already a disproportionate army of myopic asian (mostly chinese IIRC) kids that were spending their entire young lives burried in books, way before modern world glued their eyesight to those tiny crappy screens.
Now wonder if Chinese children must spend more time buried in books because their writing system is more time-demanding to learn (~4000 logograms vs. a few dozens letters in languages with alphabetic writing systems).
Everyone thinks this, until they pop out a second one and there is no time or energy to do anything outside work, cook, clean, and all the baby/toddler tasks.
It is rough if both parents are working. Lining up all the schedules and breastfeeding and whatnot is harder than it sounds, especially in northern (and southern) areas with less daylight hours. Just cooking and feeding and cleaning up after a picky toddler and baby learning how to eat can kill an evening. And then at least one is bound to be sick every other week if they are in day care…the list goes on for why plans have a low tendency to work out. See also mattlondon’s comment.
Under the age of about 1 to 1.5 then you get to call the shots of what happens when. Walk as mu h as you like.
After that age, the kids start to get their own opinions and won't always just do what you want them to do. You may want to go for a long walk, but the kid wants to do something else. They'll spend 95% of the time trying to escape the buggy/stroller or trying to run off or just sit on the floor if they're walking.
At that age we've found that it is best to not have any plans for things you need to do - e.g. don't plan to "walk to the store", because it might take you 25 minutes to go about 200 meters because you need to stop to look at a traffic light or a store front or a car that is red or whatever - i.e. you'll never get to the store without a fight. That said, they usually love the playground though so swings and slides and stuff can replace being a docile lump that you cart around.
It is not necessary that bad. I had some fights with kids at that age, but it definitely was not every single time we walked. You are exaggerating how bad it is.
What you do is normal at that age. If you walk to store frequently it is normal routine and lead to fights only occasionally. And while kid stops to look at boring things, it is not like they would stop for hours, most of time you nudge them after few seconds and they go.
It is slower then adult speed, but not that impossibly slow.
> I had some fights with kids at that age, but it definitely was not every single time we walked. You are exaggerating how bad it is.
Every child is unique. Some are more stubborn than others. This is a challenge with any parenting advice because there is so much variance. My experience is my kids do fight or linger every time despite the routine and nudges.
I'm not saying a daily walk is impossible. Rather some will find it easier than others. Still, with two working parents and car focused city planning it can be very challenging to do seemingly trivial things.
Yes, when my oldest was 1 1/2, I took him on a lot of short walks where I had no particular destination in mind. It was great for teaching him sidewalk safety and for giving him freedom to practice whatever gross motor skills he was working on, like climbing up and down steps without holding on to stuff.
Unfortunately I didn't do nearly as much of this kind of walk with his little brother, because it's not safe if your attention is divided between multiple kids.
It very much depends on the relationship you have with your kids. Respect and trust are really important.
However beyond that IMHO frankly it's critical safety imperative that children do what their parents tell them when it matters. If you're in the street near traffic a child disregarding parental instructions is a life and death issue. There are other safety critical situations too. This is why I feel it's vital that children and parents have a relationship of trust and respect, in both directions, that allows for that. It's not easy, I know.
Your kids can trust and respect you, but they still get curious and still get bored. They won't always want to do what you want them to do, especially when they are toddlers.
You need to let kids be kids (while being safe which I obviously agree with)
Kids are crazy. One second they'll be yelling in your face about how completely different from you they are, then the next minute they're repeating you verbatim to a friend.
You can absolutely get a kid excited about a long walk. It sounds like in your case your kid was enjoying it more than you were ;)
Never said that it disqualifies a concept. Just stating that there might be something else, give my anecdote. And given amount of upvotes on my comment, I'm not the only one.
Anecdata, but I lived in a low light environment for most of my life (North UK), then spend the last ~15 years in a much brighter environment (NZ). My prescription has dropped from a mid -5 to a low -4 in that time, which is a fairly large and uncommon improvement for someone middle aged. The optician put it down to where I've been living.
I know that it's common to stabilize in middle age once you stop growing, but can't find any info about it being common to reverse. Regardless, congratulations! That's a great outcome.
As I understand it, the reversion to normal vision is not caused by changing length of the eye (as you say, nobody is growing in their 40s) but rather by a degeneration of the refractive power of the materials in the eye.
In earlier years, this was correlated with highly giftedness, because IQ kids used to suck in more information which means reading a lot: https://pubmed.ncbi.nlm.nih.gov/19127804/ ;)
Yep... focusing (as in, your eyes keeping focus) on a thing that's at a fixed distance infront of you for extended periods of time seems to be very bad for your eyesight... "back in my times", the parents used to blame stuff like this on screens (tv back then), but books do the same thing. Basically all the workplace safety trainings here include the "stare at something in the distance every now and then", so you focus on something else, not just the screen <1m away from your face.
I have often wondered this myself, but the dangers of UV light seem to be well documented, with no benefits.
If you wear UV protective glasses most of the time you can almost elimate cataracts.
The UV index here in southern Australia tends to be high to extreme most days during the warmer months, so I tend to wear UV protective sun glasses anytime I'm outside.
I'm not sure there are any known benefits that outweigh the costs of UV exposure.
That said, there is emerging research that the lack of NIR light is very detrimental to all kinds of health conditions[0].
Over the past two years, I've moved to ensuring that I get plenty of indirect sunlight. As NIR can go through most clothing and foliage produced shade, it's quite pleasant and relaxing to spend time in it.
I also have large concerns with the move to thermal insulation efficiency that we now have. Indoor Air and quite easily become stagnant due to lack of outdoor exchange and the the low-emissivity glass used in high end windows block most NIR. Couple that with a lack of NIR emitters (incandescent is gone, camp fires are gone), and I think we are in for a world of hurt, even more so than today.
Indoor Air quality can be mostly solved with use of ERVs to cycle the air with minimal energy loss.
I'm not sure how you solve for low-emissivity glass other than not using it and designing your structure to limit direct sunlight exposure for the window itself and use shade/curtains/blinds for thermal control when needed.
> It is abnormal for humans to need glasses. It's also abnormal for humans to need braces and to need their wisdom teeth surgically removed.
It's not. Just because there wasn't a documented cases of weakly sighted people doesn't mean that they didn't exist. Or do you seriously believe all prehistoric humans had 20/20 eyesight?
And unless your teeth are crooked line vines you probably don't need braces from medical standpoint. Unless it causes issues to your jaw. Same with wisdom teeth.
> The list of maladies caused by modern diet and lifestyle is infinite and unknowable.
What exactly in modern diet and lifestyle causes issues that you've listed?
Soft foods cause crooked teeth. Ancestral humans ate raw tubers and other very chewy things that exercised their jaws, and the growing human body needs this resistance/exercise. If you look at modern hunter-gatherer tribes with traditional diets, they have a far lower rate of crooked teeth we'd solve with braces than the developed world.
Sterile environments/too-low pathogenic load causes allergies. The immune system expects a base-rate of infection; if it doesn't see that, it upregulates. Allergies are a first-world disease; they're far less prevalent in less developed countries, and you even see the effect in immigrants- their allergy rates go up after a few years of living in a developed country.
> Or do you seriously believe all prehistoric humans had 20/20 eyesight?
The prehistoric realities were harsh and nearsighted individuals had little chances of survival and procreation (natural selection). In the modern society perfect eye-sight is not as important for survival as in the prehistoric society, thus more tolerance to its greater variability.
> The timespan is too short for evolution to have had a considerable impact.
I am not talking about evolution as in developing new species but about survivability of naturally occurring variations. Modern humanity timespan is not enough in developing new genetic traits but long enough to alter effects of natural selection. BTW, due to advances in medicine nowadays we have children born and survive into adulthood with medical conditions that were terminal just 100 years ago. Survival variability (in developed world) is much broader that it was in recent historic past (e.g. middle-ages). This is a plain fact.
But the timeline is too short even for that. The number of children who survive today, despite genetic issues, who would not have survived 100 years ago, is miniscule compared to the extent of nearsightedness today.
Wisdom teeth used to just be a problem that either killed you, or you lived with lots of pain from, or you paid a guy to try and do something about them.
I don't know why people are so big on "we used to not need X in the distant past" tropes: yes we did, but we also just let lots of people die from it, or live a life of agony or being shunned as ugly/unclean/unable.
Crooked teeth really didn't exist in the farther out past. If you look at the jawbones of Neolithic people, they all have perfectly aligned teeth.
The theory is that we're not chewing hard enough food, which leads to insufficient jawbone growth as a kid, leading to not enough space for your teeth.
I thought it was obvious that short-sightedness (Exclusively Short term thinking) is an epidemic, nobody on Wall Street can see past the next Quarter's numbers. I don't need the economist to point that out.
Nearsightedness is what this article is about... a completely different thing. I've dealt with that my entire life... and just went through the knock-on effect of retina detachment, and surgery to correct the same. Having a bubble of C3F8 gas in your one good eye is pretty damned effective at taking you out of commission for about 4 months. Looking down hurts! I hope to be up and about, and able to drive again by the start of September, once the bubble has gone, my eye has stabilized, the surgeon has made a final check, and finally after I get new glasses.
I strongly suspect the amount of light outdoors is NOT really the issue. If you're always focused on things close at hand (as the above mentioned folks on wall street), you never allow the eyes to focus on the far horizon for an appreciable fraction of the time.
I'm surprised to learn that there's no consensus on how the eye actually focuses on objects at various distances[1]. It is also well know that the smaller an iris in a camera (or eye), the larger the range of distances that appear in focus. It seems reasonable to me that if you spend your time looking at only nearby objects (like above mentioned Wall Street residents), you'll lose the ability to see things further out that might be coming to get you.
> I strongly suspect the amount of light outdoors is NOT really the issue. If you're always focused on things close at hand (as the above mentioned folks on wall street), you never allow the eyes to focus on the far horizon for an appreciable fraction of the time.
The leading hypothesis is that light stimulates the release of dopamine in the retina, and the dopamine blocks the elongation of the eye during development. One study showed that injecting a dopamine-inhbiting drug into the eyes of chicks abolished the protective effect of bright light, and myopia increased. See https://iovs.arvojournals.org/article.aspx?articleid=2126968
Your particular confidence on this ("strongly suspect") bothers me because it has an influence on others, yet it is totally ignorant of what current scientific findings suggest.
All of the experiments you mentioned happened indoors. How can you have far field (> 100 meters distant) objects inside a laboratory? None of those experiments rule out my hypothesis.
Your hypothesis is that myopia is primarily caused by the lack of focus on far-field objects.
In a lab environment, wherein there is a lack of focus on far-field objects, myopia does not occur when there is sufficient light intensity. On the other hand, it occurs with insufficient light intensity.
If your hypothesis were correct, then myopia would occur regardless of light intensity, because all of the subjects have a lack of focus on far-field objects. But it doesn't. It only occurs with insufficient light intensity.
Does it? This isn’t a scientific journal, nor is this a hard science forum. So the expectations that a layman conform to the standards of a field to have a conversation about a fairly esoteric subject is asinine.
I can’t know the top science in every field, so that bars me from discussion, lest I be slammed for having a thought.
This isn’t just anti-science, it’s ignorant of social interactions, and the conversations that lead to greater understanding. You aren’t nearly as smart as you think you are.
I guess the spirit of what you're saying is that I reacted with excessive condemnation. Yeah, you're right. Truth is important and I don't regret the information I gave out, but I agree that I should have taken it easier.
On that note, I guess it's a little fun that you ending with "you aren’t nearly as smart as you think you are" seems to be participating in the same unnecessary meanness that you just called out. Ahhhh man, aren't we all so brutally human...
Yes, that's the definition I've always held. Had 20-20 vision but through working online (and likely smoking) my vision is not 20-20 any more. Short sighted, long sighted - is a bit counter intuitive but covers it.
Funny you say that because I'm British and only hear and say "near-sightedness". I certainly wouldn't be offended by "short-sighted" but instead confused because it has dual meanings.
> I thought it was obvious that short-sightedness (Exclusively Short term thinking) is an epidemic, nobody on Wall Street can see past the next Quarter's numbers. I don't need the economist to point that out. Nearsightedness is what this article is about... a completely different thing.
Is it ironic or just poetic that this is a myopic take on the meaning of the word "shortsighted"?
This feeds into my pet peeve that Americans assume the world revolves around them and that all use of non American English is invalid despite the stereotype being that British English speaking people are worse for this.
I believe there is a Will Self story in which a geological probe reaches the Earth’s core and finds the compressed remains of an American around whom the planet is in fact revolving.
It's not so much invalid as confusing. For Americans to call someone "shortsighted" has a well-known usage and negative connotation about their intellectual integrity. As someone who had never encountered the British usage prior to this headline, I don't think it's out of line to remark on this as a weird curiosity of our shared (but also frequently as in this case not shared) language.
I suspect folks are more irked by the parochial condescension with which the initial complaint was voiced, rather than the fact of the observation. This is not a forum that generally smiles upon weaponised imbecility.
You need not be disturbed by this. Every nation/culture tends to think in terms of the world "revolving" around them. A people need a frame of reference to view the world that is provided by one's culture. I don't think the OP intented to treat British English as inferior or invalid.
Sorry, but in Australian English, those with myopia are always referred to as being short-sighted. The metaphor, having lack of foresight, is also referred to by the same expression.
Not him, but myopia is the correct medical term. It only has one meaning, whereas "short-sighted" has a widely used metaphorical meaning that it is easily confused with.
I would find “Near sightedness less ambiguous, in American English at least. I can’t remember having heard that used for anything other than a physical difficulty to focus your eyes at longer distances.
I am from the US, and have heard “shortsighted” used as a synonym for “myopia” all my life. “Nearsighted” is more common, but not exclusive to non-US English. Wikipedia backs up the idea that they are all synonyms, as well.
>nobody on Wall Street can see past the next Quarter's numbers. I don't need the economist to point that out.
This funny to read on a tech oriented website.
I agree that the quarter by quarter financial goals can be a "shortsighted", and I think the problem is even worse when it comes to the 4 year political cycle (2 years if you consider the fact the Houses can change hands).
But Wall Street is still filled to the brim with public companies espousing some future fantasy profits that may or may not ever come. We are as far away from shortsightedness there as we've ever been. One only has to looks at ARKK research to see this.
From an optical perspective, focusing on something a few meters away is basically infinity for the eye. Even indoors you do that a lot, which makes the "focus close -> loose infinity" theory less plausible compared to light levels, which we know have a very significant impact on the whole body. Focusing very closely all the time (again, optically speaking, a screen 1 meter away is closer to infinitely far away than to a smartphone in the face) might do and explain something.
I also made the same mistake and assumed the article was about shortsighted thinking. But I've also always found the term "nearsighted" to be very confusing as well. I always confuse the meaning with "farsighted," ie not being able to see things near you.
It's very true that there is nothing to focus on that is further than the next tall building in that area, add it to looking at the screen like its life or death all day
It may just be a pet peeve, but it rankles me a bit when the term "epidemic" is used to describe widespread conditions that are not communicable/infectuous. Looking at the dictionary it appears the usage here is legitimate, but my guess would be that it is a misuse that has become accepted, like using the term "begging the question" to mean suggesting the question.
Epidemiologists study health at the population level in general, not just communicable diseases. So at least in that sense the "epidemi-" prefix isn't limited to infection. Is there any better term for a health issue with rapidly increasing prevalence?
A dictionary of medicine from 1882 suggests that common usage of the word has become more narrow, not less, and that there was some level of debate about the technical meaning [1]. Stedman's Medical Dictionary (1920) gives a more modern definition, "a disease attacking nearly simultaneously a large number of people", without restriction to infectious diseases.
>but it rankles me a bit when the term "epidemic" is used to describe widespread conditions that are not communicable/infectuous
but short sightedness caused by lack of sunlight exposure is infectuous.
why do you think kids are being kept at home? because of their parents. and why do the parents keep them at home? because of a cultural and societal shift in behavior. and why is this shift happening? because some ideas floating around have infected a large enough number of people.
human ideas (or memes if you like) are precisely like viruses, and if short-sightedness is caused by some ideas being spread then it's no different than it being an actual virally caused disease.
You should probably leave it to the Academies, given that others take the opposite general stance.
What the server /accepts/ is left to configuration (some still recommend, "Strict in formulating the output, loose in interpreting the input"). What is "legitimate" is another matter, and will have to consider the term's curriculum, also because other proposals are faulty (e.g. conventionalism: "/whose/ convention?").
I don't know about shortsightedness but for instance obesity is a legitimate epidemic. Whipe it is behavioural it is well known that social groups influence each other on this, so like a virus it spreads between people. The same may be true for shortsightedness too to some degree.
The medical use is not strictly tied to infection, as the OP would have expected. In Hippocrates, "epidemic" vs "endemic" is akin to "temporary" vs "permanent".
Please do also see the sibling post from member 'one-more-minute'.
This is a common figurative use of the word. The etymology comes from the Greek meaning "upon/on people", so nothing in the root connects the meaning to how something develops or spreads.
Each pandemic is also epidemic. Pandemics are subset of epidemics. The word pandemic existing does not make the use of word epidemics incorrect.
Also, pandemic is not normally used in non medical context while epidemics is frequently used that way and was for years. The journalist probably decided to use the common words in their common meaning instead of going for obscure usages.
Agree man! Lockdown was just really unjustified on society.
It made no sense for such a minor disease which I'm sure would have been dismissed as flu 60 years ago.
I don't know what caused this overreaction, sure for 30-40 days but this thing has devastated billions of lives, left millions jobless and ruined an entire generation.
It's sometimes necessary to have pandemics and diseases like this to control the population of society.
Europe practically had a renaissance after the black death.
It isn't recommended to stare directly at the sun, and I think the suggested amount to spend outside each day as a child to prevent myopia is ~2 hours, but don't quote me on that.
I paid nearly $1500 for my kid myopia treatment plan: specialized drop, checkin every 2 months. Nothing helps. They now recommend I do contacts for my 9 year old and I kindly say hell no. I think this is scammy at best.
My hypothesis is that less sunlight means wider pupils and more defocus (contrast to a pinhole camera), so more eye growth.
Even with perfect eyesight, there's a 2-diopter difference between focussing blue light and red light due to chromatic aberration. Only narrow pupils can reduce this blur in white light.
I'm also curious whether older TVs with big blurry pixels (or low res images upscaled and smeared onto newer screens) trigger the same mechanism. These days I certainly feel physically uncomfortable looking at media like that, like my eyes aren't focussing quite right.
The other problem is that once eyes have grown too long and are myopic (near-sighted) they experience even more defocus and grow more. See for example [1] which discusses how under-correction of myopia accelerates progression.
[1] https://reviewofmm.com/does-the-undercorrection-of-myopia-in...