Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hi
Speaker 1: brain Stuff, Lauren bogel Bam here with another classic episode
Speaker 1: from our podcast archives. The world is increasingly near sighted,
Speaker 1: and I'm not talking metaphorically. Researchers say that by the
Speaker 1: year twenty fifty half of the world will be near sighted.
Speaker 1: Today's question is why, Hey, brain Stuff, Lauren bogel Bam here,
Speaker 1: there's a myopia epidemic going on. In n seventy two,
Speaker 1: about of Americans aged twelve to fifty four were diagnosed
Speaker 1: with this condition, which is also called near sightedness. But
Speaker 1: today some forty of young Americans are receiving the same diagnosis.
Speaker 1: And that's nothing compared to Asian countries, where of high
Speaker 1: school kids are now near sighted. In seal, ninety six
Speaker 1: point five percent of nineteen year old males are myopic,
Speaker 1: and researchers say that by the year twenty fifty five
Speaker 1: billion people will be wearing glasses to combat near sightedness.
Speaker 1: That's more than half the people in the world. How
Speaker 1: did this happen so fast and so many people. While
Speaker 1: intuitively you might think it has something to do with
Speaker 1: all the time we spend staring at computer or smartphone screens,
Speaker 1: it's not so cut and dried. The rise and near
Speaker 1: sightedness started happening before the prevalence of those screens, and
Speaker 1: has been studied at least since the nineteen sixties. The
Speaker 1: latest research reveals that the world's rising myopia rates stem
Speaker 1: from spending too much time indoors. In general, several studies
Speaker 1: show the less time children spend outdoors, the more likely
Speaker 1: they are to develop myopia. This could explain the much
Speaker 1: higher myopia rates in Asian countries, where a stronger focus
Speaker 1: on education keeps kids indoors for more hours than children
Speaker 1: living in most other parts of the world. We spoke
Speaker 1: with Dr Adam Claren, a Florida optometrist. He said the
Speaker 1: progression of the number of myoptic patients has risen too
Speaker 1: fast to be explained by genetics alone. Unfortunately, the data
Speaker 1: is not conclusive enough to determine what parts of being
Speaker 1: outside is protective against myopia. Is that the sunlight, is
Speaker 1: it looking at distant objects, or is it something we're
Speaker 1: not even thinking about. Near sightedness is caused by an
Speaker 1: elongated eyeball. Normally, the light that flows into your eyes
Speaker 1: focused directly on the surface of the retina, but if
Speaker 1: your eyeball is a bit too stretched out, the lens
Speaker 1: will focus the lights slightly in front of the retina instead,
Speaker 1: resulting in blurry vision. The hypothesis about myopia that's gaining
Speaker 1: the most traction says that when the neurotransmitter dopamine is
Speaker 1: released into the retina, it prevents your eyeball from elongating
Speaker 1: and blurring your vision, and light is what stimulates this
Speaker 1: release of dopamine. Normally, a pair of glasses or contact
Speaker 1: lenses is all that's needed too sharpen your vision. However,
Speaker 1: of those with the condition have a heightened form called
Speaker 1: high myopia. People with high myopia are at a risk
Speaker 1: for developing cataracts, glaucoma, torn or detached retinas, and even blindness.
Speaker 1: Although no one knows how much time spent outdoors is
Speaker 1: enough to forestall myopia, one researcher at the Australian National
Speaker 1: University in Canberra estimated the amount at three or more
Speaker 1: hours per day. It's also possible that strong indoor lights
Speaker 1: could help, but Dr roheat Varma, director of the University
Speaker 1: of Southern California I Institute, told us via email that
Speaker 1: even if the myopia boom is not directly related, to
Speaker 1: children spending more time indoors looking at a screen quote,
Speaker 1: These are two sides of the same coin. Spending more
Speaker 1: time indoors equates to spending less time outdoors, especially during
Speaker 1: the day. Researchers are still trying to determine the real
Speaker 1: fix for the myopia epidemic. Dr Claarin said other studies
Speaker 1: have shown that a low dose of atropine eye drops
Speaker 1: can also slow the progression of myopia. These studies are
Speaker 1: completely unrelated to the studies on being outdoors, so there's
Speaker 1: obviously more than one mechanism at play. Hopefully, continuing research
Speaker 1: will shed some light on this growing problem. Today's episode
Speaker 1: is based on the article half the World will be
Speaker 1: near sited by fifty on how stuff works dot Com,
Speaker 1: written by Melanie Radzekei McManus. Brain Stuff is production by
Speaker 1: Heart Radio in partnership with how stuff Works dot Com
Speaker 1: and is produced by Tyler Clay. Four more podcasts my
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