The View From the Center of the World’s Myopia Epidemic

In Taiwan, so many people are nearsighted that the island nation has already glimpsed what could be coming for the rest of us.

DOING SURGERY ON the back of the eye is a little like laying new carpet: You must begin by moving the furniture. Separate the muscles that hold the eyeball inside its socket; make a delicate cut in the conjunctiva, the mucous membrane that covers the eye. Only then can the surgeon spin the eyeball around to access the retina, the thin layer of tissue that translates light into color, shape, movement. “Sometimes you have to pull it out a little bit,” says Pei-Chang Wu, with a wry smile. He has performed hundreds of operations during his long surgical career at Chang Gung Memorial Hospital in Kaohsiung, an industrial city in southern Taiwan.

Wu is 53, tall and thin with lank dark hair and a slightly stooped gait. Over dinner at Kaohsiung’s opulent Grand Hotel, he flicks through files on his laptop, showing me pictures of eye surgery—the plastic rods that fix the eye in place, the xenon lights that illuminate the inside of the eyeball like a stage—and movie clips with vision-related subtitles that turn Avengers: Endgame, Top Gun: Maverick, and Zootopia into public health messages. He peers at the screen through Coke bottle lenses that bulge from thin silver frames.

Wu specializes in repairing retinal detachments, which happen when the retina separates from the blood vessels inside the eyeball that supply it with oxygen and nutrients. For the patient, this condition first manifests as pops of light or dark spots, known as floaters, which dance across their vision like fireflies. If left untreated, small tears in the retina can progress from blurred or distorted vision to full blindness—a curtain drawn across the world.

When Wu began his surgical career in the late 1990s, most of his patients were in their sixties or seventies. But in the mid-2000s, he started to notice a troubling change. The people on his operating table kept getting younger. In 2016, Wu performed a scleral buckle surgery—fastening a belt around the eye to fix the retina into place—on a 14-year-old girl, a student at an elite high school in Kaohsiung. Another patient, a prominent programmer who had worked for Yahoo, suffered two severe retinal detachments and was blind in both eyes by age 29. Both of these cases are part of a wider problem that’s been growing across Asia for decades and is rapidly becoming an issue in the West too: an explosion of myopia.

Myopia, or what we commonly call nearsightedness, happens when the eyeball gets too long—it deforms from soccer ball to American football—and then the eye focuses light not on the retina but slightly in front of it, making distant objects appear blurry. The longer the eyeball becomes, the worse vision gets. Ophthalmologists measure this distortion in diopters, which refer to the strength of the lens required to bring someone’s vision back to normal. Anything worse than minus 5 diopters is considered “high myopia”—somewhere between 20 and 25 percent of myopia diagnoses around the world are in this category. In China, up to 90 percent of teenagers and young adults are myopic. In the 1950s the figure was as low as 10 percent. A 2012 study in Seoul found that an astonishing 96.5 percent of 19-year-old men were nearsighted. Among high schoolers in Taiwan, it’s around 90 percent. In the US and Europe, myopia rates across all ages are well below 50 percent, but they’ve risen sharply in recent decades. It’s estimated that by 2050, half the world’s population will need glasses, contacts, or surgery to see across a room. High myopia is now the leading cause of blindness in Japan, China, and Taiwan.

If those trends continue, it’s likely that millions more people around the world will go blind much earlier in life than they—or the societies they live in—are prepared for. It’s a “ticking time bomb,” says Nicola Logan, an optometry professor at the UK’s Aston University. She wasn’t the only expert I talked to who used that phrase. Because so much of Taiwan’s population is already living life with myopia, the island nation has already glimpsed what could be coming for the rest of us. And in a rare confluence, the country may also be the best place to look for solutions.

ON THE BULLET train south from Taipei, you can see the smog hanging over Kaohsiung from miles away, blurring the edges of the buildings. During the Japanese occupation, which ended in 1945, what had been a small trading port transformed into one of Taiwan’s biggest cities, a riot of heavy industry and shipbuilding. Over the next four decades, as Taiwan made the rapid transition from a predominantly agricultural economy to a manufacturing powerhouse, the lives of its citizens shifted too. Families flocked into cramped apartment blocks that still make up much of the urban housing. Education for children was mandatory and became increasingly intense. A network of after-school establishments called “cram schools” sprang up, making room for parents to work long hours without the childcare support from elderly relatives they would’ve had in the old society. At the end of the school day, some kids would board a bus, not to go home, but to ride to their cram school, some of which were open until 9 pm.

Pei-Chang Wu was born in Kaohsiung, at the height of the city’s transformation, in 1970. His grandparents, neither of whom were myopic, were farmers in central Taiwan. Both of his parents were teachers, and like many Asian parents, they put a huge emphasis on education as one of the few levers they could pull to move up through society. His father enforced a strict daily routine: up at 5 am for calligraphy and violin practice, school from 7:30 am to 4 pm. Once Wu got home in the evenings he had to complete his schoolwork. On the weekends, he participated in calligraphy competitions. By the age of 9, Wu had been diagnosed with myopia.

Across the modernizing world, this pattern repeated itself. For economies to continuously expand, education had to become central, and as this happened, the rates of myopia started to climb. But hardly anyone noticed, in Taiwan or anywhere else.

If current trends continue, it’s likely that millions more people around the world will go blind much earlier in life than they—or the societies they live in—are prepared for.

Then, during one summer in the early 1980s, a group of incoming college students gathered at Chengkungling, a military training facility in central Taiwan, for a ceremony to mark the beginning of their mandatory national service. The United States had recently cut diplomatic ties with the island and formally recognized the government in Beijing, and cross-strait tensions were high.

At first, the early morning ceremony went smoothly. A single cadet—tall, good posture—received a rifle on behalf of his classmates, symbolizing their duty to defend their country. As the ministers of education and defense rose to deliver their speeches to the young men they hoped would be the future of Taiwan, the sun also rose higher into the sky behind the stage. The government officials were dazzled by the glare reflecting back at them from hundreds of pairs of glasses. The ceremony was the seed for a joke about how to ward off an alien invasion—just ask Taiwanese students to look up—and the spark for the government’s fight against myopia.

The first step was to understand the scope of the problem. The president, alarmed by what had happened, asked health officials to begin a regular survey of myopia rates in Taiwan. It revealed a previously hidden epidemic, which seemed to be getting worse. By 1990, the myopia rate among Taiwanese 15-year-olds had risen to 74 percent.

By the time Wu started medical school in the early 1990s, he was seeing floaters—“strange animals in the sky,” as he called them—when he closed his eyes. At first, he dismissed them and focused on his budding career as an ophthalmologist. But during his residency, Wu examined hundreds of patients with retinal detachments who’d had the same symptoms. He grew worried about his own long-term vision. So he asked one of his professors to examine his eyes. “He found a break in my retina,” Wu said.

He was lucky. It was a small tear, minor enough to be fixed with a laser in five minutes. Shining a light through the pupil creates scar tissue that the retina can reattach to. “The laser saved me,” Wu said. “Otherwise I would be blind in one eye.” Wu decided he had a responsibility to rescue others from high myopia and its potential complications. “If I cannot save myself, we should save our next generation.”

It wasn’t until the mid-1990s that a better understanding of what caused myopia—and what could prevent it—finally cracked open.

In 1999, the government convened a group of experts in medicine and education to try and fix the problem. Jen-Yee Wu, who worked at the Ministry of Education and had done his doctoral thesis on eyesight protection, was asked to write a set of guidelines for schools to address nearsightedness.

Later that year, he published a thin green book full of advice for teachers. It paid careful attention to desk height (to keep texts the right distance from the eyes) and room lighting, and advocated eye relaxation exercises, including a guided massage of points around the eyes and face. The book also advised giving children more space in their notebooks to pen the intricate characters that make up written Mandarin. And it formalized the 30/10 rule: a 10-minute break to stare into the distance after every half hour of reading or looking at a screen.

None of it worked. Nearsightedness rates continued to climb because, as it turned out, Taiwan, and the world, had been thinking about how to address myopia completely wrong.

HERE IS A non-exhaustive list of things that have been blamed for nearsightedness: pregnancy, pipe smoking, brown hair, long heads, bulging eyes, too much fluid in the eyes, not enough fluid in the eyes, muscle spasms, social class. “Any ophthalmologist who experienced a night of insomnia arose in the morning with a new and usually more bizarre theory,” wrote Brian Curtin in an influential 1985 book about myopia.

Folk theories have changed with technologies. Ask people today and they’re likely to blame smartphones and video games. Before that, it was sitting too close to the television and reading under the covers with a flashlight. Those activities all come under the broad umbrella of “near work”—using your eyes to look at something close to your face—which had been the leading scapegoat for myopia for centuries. In 1611 the astronomer and scientist Johannes Kepler wrote, “Those who do much close work in their youth become myopic.” In the mid-19th century, there existed a contraption called the “myopodiorthicon,” which was designed to gradually move a book backward during reading to strengthen the eye’s ability to adjust to objects at different distances. The Hygiene of the Eye in Schools, by Hermann Cohn, published in 1883, paid careful attention to lighting and advocated the use of headrests to physically prevent the eyes from coming too close to the text during reading.

In 1928, British ophthalmologist Arnold Sorsby surveyed Jewish boys in East London and discovered that they were more myopic than their non-Jewish peers. At first, he thought this was because of the extra time spent doing near work while studying holy texts. Eventually, though, he came to believe there was a genetic element to myopia. He conducted studies of twins that seemed to confirm this: The severity of myopia was more similar among identical twins than fraternal twins. The science of genetics was in vogue, and as Sorsby’s theory swept away Victorian concerns about the state of the schoolhouses, it became dogma for decades. Myopia became seen as a condition to be managed, not a disease that could be prevented.

It wasn’t until the mid-1990s that a better understanding of what caused myopia—and what could prevent it—finally cracked open. In these years, an Australian researcher called Ian Morgan stumbled on a scientific mystery that would consume the next 25 years of his life. Morgan, now a genial 78-year-old with sun-wrinkled skin and large dark-framed glasses, was working as a research fellow at the Australian National University in Canberra, where he was studying the neurotransmitter dopamine and its role in the eye’s signaling systems. Back then, he didn’t know much about myopia—he could barely tell you the difference between far- and nearsightedness.

Pei-Chang Wu with a patient. PHOTOGRAPH: AN RONG XU

But as a part of his weekly reviews of the latest scientific literature, he started to see some of the first evidence coming out of Asia about the growing myopia epidemic. He couldn’t understand how myopia rates could be close to 80 percent for kids leaving high school in East Asia and so much lower in his native Australia.

He soon found other research casting doubt on Sorsby’s genetic view of myopia. In Inuit and Eskimo populations, during the 1970s, myopia incidence increased from 5 percent to more than 60 percent prevalence in the span of one generation. Genetics couldn’t explain such a jump. The sharp increase in schooling among younger Inuits, however, might. In the early 1990s, researchers had found that ultra-orthodox Jewish boys are more myopic than their sisters—something that was likely due to the extra studying they have to do.

Morgan started to seek out a better understanding of what causes myopia, and by the early 2000s, he was convinced there had to be a behavioral reason for the boom. But if near work was really to blame, why hadn’t the interventions tried in China and Taiwan made any difference? In 2003, with colleagues Kathryn Rose and Paul Mitchell, Morgan began a two-year study of thousands of 6- and 12-year-olds in Sydney, looking for lifestyle differences that might explain their lower levels of myopia. They used a technique called “cycloplegic autorefraction,” in which the patient’s eyes are first relaxed with eye drops before a machine measures how light is focused on the back of the eye, providing an objective measure of the length of the eyeball.

The results, which were published in a landmark 2008 paper, confirmed Morgan’s suspicions. As expected, overall myopia rates among Australian 12-year-olds, at about 13 percent, were significantly lower than in Asia. Morgan and his team also surveyed the participants about their daily routines and hobbies and discovered a surprising relationship. The more time kids spent outside, the less likely they were to have myopia.

The next question was why. “This was where my background became really important,” Morgan says. It all came back, he thought, to dopamine—the neurotransmitter he had been studying before his detour into myopia research. “We knew that light stimulated the release of dopamine from the retina, and we knew that dopamine could control the rate at which the eye elongated,” Morgan says. (In 1989, an American ophthalmologist named Richard Stone found that he could induce myopia in chickens by manipulating light levels, and that there was less dopamine in the retinas of the myopic chickens.) “So once we had the actual epidemiological evidence that being outdoors was important, the mechanism was, to us, very obvious.” Without adequate exposure to sunlight, the eye keeps growing longer, images are focused in front of the retina, and vision becomes blurry. In August 2008—after a decade of research—Morgan published a paper that he believed contained the key to solving Asia’s myopia epidemic.

AROUND THIS TIME, Wu’s clinic was busy—his operating table often full, with a steady stream of parents with young children in tow seeking treatments for myopia. For instance, orthokeratology contact lenses improve vision by temporarily squishing the cornea into a different shape, reminiscent of how ancient Chinese soldiers are said to have slept with sandbags over their eyes for the same effect. Then there’s atropine—a muscle relaxant derived from the toxic nightshade and mandrake plants. Nightshade has been known as “belladonna” because women in Renaissance Italy—and maybe even as far back as Cleopatra—used it to dilate their pupils to make them appear larger and more beautiful. Atropine paralyzes the ciliary muscle, which controls the size of the pupil and, for reasons scientists haven’t yet pinned down, also seems to slow down the progression of myopia. (Since 2008, new treatments have become available: miSight contact lenses and MiyoSmart glasses, which arrest the growth of the eye by manipulating light patterns.)

In his studies in Taiwan, Wu observed the same phenomenon that Morgan had documented: More outdoor time equalled less myopia

But Wu knew that none of these treatments were dealing with the underlying cause of the problem. And as a newly minted member of Taiwan’s Vision Care Advisory Committee, a different group of academics behind some of the country’s well-meaning but ineffective attempts to tackle nearsightedness, he had adopted a determined, systematic approach to finding a solution. Every week, he gathered his colleagues to review the latest academic research on myopia. He even corralled his mother into making snacks as an added incentive.

During one of these Thursday sessions, with the smell of home-cooked food in the air, Wu discovered Ian Morgan’s research in Australia. It was a eureka moment. Were Taiwan’s classroom interventions failing because kids weren’t spending enough time outside? Wu decided to run his own version of the Sydney Myopia Study in Cimei, an island off the west coast of Taiwan. He observed the same phenomenon: More outdoor time equalled less myopia.

Around the same time, Wu chanced on an opportunity to go a step further than Morgan—to move from simply observing the myopia problem to fighting back. His son was starting elementary school, and the parents of incoming students had been invited to an orientation talk. They gathered in a classroom at the school, surrounded by small desks and kids’ drawings on the walls. At the end, the principal opened the floor to questions. Wu raised his hand and voiced his concerns about what Taiwanese schooling might do to his son’s vision. “Under your education system, will he become myopic or not?”

Other hands started going up. One woman had a daughter in the third grade who was already minus 2 diopters, and she feared for her son. Wu saw a chance to put Morgan’s theory into action.

At the time, the Taiwanese government was encouraging schools to switch the classroom lights off and send kids outside during breaks—to save electricity, not eyes. Wu convinced the principal of his son’s school to go further and usher the children outside six times a day, which added up to an extra six and a half hours of outdoor time each week. When Wu took measurements at the start of the program, in February 2009, the myopia prevalence among 7- to 11-year-olds at both his son’s school and another school, which he used as a control for his experiment, was around 48 percent. A year later, the control school had almost twice the rate of new cases of myopia as his son’s school.

Wu began to preach the gospel of outdoor time, appearing in the media and touring rural Taiwan. On many of the stops, Wu, on guitar, and his wife, on keys, play their own renditions of pop songs with new lyrics about myopia prevention. (A recent effort turned “Despacito” into a ballad about atropine). He wrote a book, Kids Could Be Free From Myopia, outlining the principles of good eye health and how he applied them to slow the progression of myopia in his own young children. “Sometimes,” he says, “we don’t appreciate the free things.”

Wu also worked on translating his research findings into a simple program that could be rolled out across the country. To do that, he needed to know how much time kids should spend outdoors. Wu thought back to Ian Morgan’s research, which had found that Australian kids spent an average of 13.5 hours a week outside. Another study suggested 14 hours. And so two hours a day became the cornerstone of Taiwan’s national myopia strategy, launched in 2010. It’s called Tian-Tian 120, which translates to “every day 120,” for the number of minutes children should spend outside each day.

At Mingde Elementary School in Kaohsiung, I watched as muzak blasted over the speakers and kids of all ages came streaming outside in their uniforms, grabbing balls and jump ropes. As the school’s principal, Ching-Sheng Chen, proudly showed off the array of outdoor equipment, a boy who couldn’t have been much older than 7 grabbed a unicycle and began riding laps around the playing field. At another school in northeast Taiwan, known for its changeable weather, the playground has been equipped with a giant covered area called “Sunny Square” so the kids can still spend time outdoors when it’s raining.

The results of the Tian-Tian 120 program were immediate and impressive. After years of trending upwards, myopia prevalence among Taiwanese primary school children peaked in 2011 at 50 percent, and then started to come down. Within a few years, it was at 46.1 percent. “You can see this very beautiful curve,” Wu says.

IN 2014, A young ophthalmologist in Yilan County, on Taiwan’s rugged northeast coast, began a project that he hoped would eradicate high myopia entirely.

Der-Chong Tsai—who wears round black frames and a white lab coat and shares Wu’s earnest energy—first became interested in eye health while training at Taiwan’s National Defense Medical Center. From there, he worked at Taipei Veterans General Hospital, and he’d come across Wu’s and Morgan’s work on nearsightedness after completing a PhD in epidemiology in the early 2010s.

He was impressed but had a hunch that intervening even earlier than primary school could make a significant difference—not only to slow down the progression of myopia, but to try and stop it from taking hold in the first place. It’s been found that for every year the onset of myopia is delayed, the ultimate severity of the condition is reduced by 0.75 diopters—catch it early enough, and you might be able to prevent a kid from ever needing glasses. “We thought primary school was too late,” Tsai said. “In terms of myopia prevention, the earlier the better.”

Taiwan finally seemed to be getting the upper hand in its long fight against myopia. Then Covid hit, and Wu’s beautiful curve began to invert.

Yilan County now runs one of the most ambitious myopia prevention programs in the world. Each year, Tsai and his team visit every preschool in the region, running screening tests to look for what’s called “pre-myopia”—the earliest signs of the eyeball getting too long. Tsai wants to catch children whose eyes are already too long for their age—who may not have myopia yet, but who might be at higher risk once they start formal schooling.

Today, Tsai screens more than 98 percent of preschoolers in Yilan County, and at a cost of just $13 per child, he’s found hundreds of cases of pre-myopia that wouldn’t have been spotted until much later, when it was more advanced. The children most at risk of developing myopia are prescribed atropine alongside their time outdoors, and the results have been spectacular. By the end of 2016, after two years, the Yilan program had driven down the prevalence of myopia in the region by 5 percentage points. Between the Tian-Tian 120 initiative, aimed at older kids, and the Yilan program, Taiwan finally seemed to be getting the upper hand in its long fight against myopia.

Then Covid hit, and a whole generation of kids were stuck inside for months at a time. Studies show that in China, Turkey, Hong Kong, and India, myopia worsened during the Covid lockdowns. Taiwan was no exception: Wu’s beautiful curve began to invert.

IN MARCH 2023, Taiwan lifted its final pandemic restriction, allowing international travelers to visit without having to quarantine. I arrived there half-expecting some mythical Land of the Blind scenario: pavements populated by people with white sticks stumbling into everything, a pair of glasses perched on every nose. It wasn’t like that, of course. Although there were seven eyewear shops within a 10-minute walk of my hotel in Kaohsiung, and the stylized eye logos of oculists all around, like the eerie billboard from The Great Gatsby.

There are long-standing cultural forces driving Taiwan’s myopia boom—the emphasis on education and a notion that paler skin is more attractive both conspire to keep people inside. Navigating the organized chaos of traffic snarls in cities like Taipei and Kaohsiung, I couldn’t help but think how difficult it would be for someone with impaired vision to get around, and how challenging it is to find safe outdoor spaces for children to play in the sun in such a dense metropolis.

But the pandemic has entrenched what was already a global problem. On our current trajectory, viral diseases, air pollution, and extreme heat are just some of the things that will continue to keep young children indoors. By 2050, according to the International Myopia Institute, 10 percent of the world’s population will have high myopia, and up to 70 percent of them will have pathologic myopia—the kind that causes blindness. That’s as many as 680 million people affected by vision loss or blindness, with catastrophic effects for economies and health care systems.

In that sense, Taiwan’s myopia boom is a blurry glimpse of a potentially blurred future: one where technology has to compensate for the societal changes that are driving nearsightedness. Ian Morgan has been involved in prototypes of glass-walled classrooms in China, enabling children to get the benefit of time outdoors without having to cut back on education. Other research suggests that shining a bright red light directly into the eye with a special machine may slow the progression of myopia. But many of the existing treatments are expensive, and they don’t work for everyone. Some ophthalmologists predict a future where bad eyesight, like crooked teeth, becomes a marker of an impoverished childhood. Others argue that myopia prevention should be publicly funded—that, like programs to encourage people to quit smoking or exercise regularly, a little funding now will save a lot in the future. “Prevention is better than cure,” is one of Pei-Chang Wu’s mantras.

While children in Taiwan’s Yilan County experienced the pandemic years much the same as kids everywhere—less time outdoors and more time watching screens—intervening when children are quite young has proven to be the best strategy: Across the county, myopia rates in preschoolers remained stable throughout the lockdowns. Technology and industrialization may have contributed to the myopia problem, but sometimes the best solutions are cheap and simple. Just go outside, and see.

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