Myopia, or nearsightedness, affects roughly 30% of the global population, making it one of the most common vision conditions in the world. That number is climbing fast. In the early 1970s, about 25% of Americans were nearsighted. By the early 2000s, that figure had jumped to nearly 42%, a 66% increase in just three decades. In parts of East Asia, the rates are even more striking, with 80 to 90% of high school graduates affected.
Global Prevalence by the Numbers
A comprehensive meta-analysis published in the British Journal of Ophthalmology tracked myopia prevalence in children and adolescents from 1990 through 2023. The pooled global rate rose from about 24% in 1990 to nearly 36% by 2023. Projections put the number at roughly 40% by 2050.
The Brien Holden Vision Institute’s widely cited forecast is even more dramatic when translated into raw numbers: by 2050, an estimated 4.8 billion people (nearly half the world’s population) will be nearsighted. Of those, close to 938 million will have high myopia, meaning their prescription exceeds negative six diopters. High myopia isn’t just a thicker pair of glasses. It fundamentally changes the shape of the eye in ways that raise the risk of serious complications later in life.
Where Myopia Is Most Common
East Asia has the highest rates on the planet. In China, a large-scale systematic review found that overall myopia prevalence in children was 36.6%, but that average masks a steep age curve. Among children aged 5 to 9, about 22% were nearsighted. By ages 10 to 14, the rate doubled to 45%. Among teenagers aged 15 to 19, fully 67% had myopia. High myopia followed a similar trajectory, reaching 9.5% in that oldest teenage group.
Urban areas in several East Asian countries report rates of 80 to 90% among students finishing high school, with 10 to 20% of those students progressing to high myopia. South Korea and Singapore see comparable numbers. These rates far exceed what’s observed in most Western countries, though the gap is narrowing.
Rising Rates in the United States
The U.S. has seen its own sharp increase. Data from the National Health and Nutrition Examination Surveys showed myopia prevalence climbing from 25% in the 1970s to about 42% in the early 2000s. A separate long-running study in Olmsted County, Minnesota tracked an even steeper rise: from 34% in the 1960s to 57% in the 2010s, a 68% increase. While the U.S. hasn’t reached the levels seen in East Asia, the trend line is moving firmly in the same direction.
Why Rates Keep Climbing
Genetics plays a role. If both parents are nearsighted, a child is significantly more likely to develop myopia. But genes alone can’t explain a doubling or tripling of prevalence in a few decades. The shift is largely environmental.
Two factors stand out: more time doing close-up work and less time spent outdoors. A meta-analysis in The Lancet Digital Health found that each additional hour per week of near-vision work increased the odds of myopia by about 2%. Smart device screen time on its own raised the odds by 26%, and when combined with regular computer use, the risk jumped by 77%. Children today spend far more cumulative hours focused on screens, books, and devices at close range than any previous generation.
Outdoor time appears to be protective, and the mechanism likely involves bright natural light stimulating the release of a chemical in the retina that helps the eye maintain its proper shape during growth. Population studies consistently show that children who spend at least two hours outdoors daily are significantly less likely to develop myopia. The benefit is strongest during late morning to mid-afternoon, when ambient light levels are highest. This finding has prompted public health campaigns in several East Asian countries encouraging more recess and outdoor play.
Why High Myopia Matters
Most people think of nearsightedness as an inconvenience corrected by glasses or contacts. For mild to moderate cases, that’s largely true. High myopia is a different story. As the eye elongates to higher degrees of nearsightedness, the retina stretches thinner, and structural damage becomes increasingly likely over a lifetime.
At a prescription of negative six diopters, the risk of retinal detachment is nine times higher than in someone without myopia. The risk of glaucoma triples. Most dramatically, the odds of myopic maculopathy, a form of damage to the central retina that can cause permanent vision loss, are 41 times higher. These aren’t rare outcomes at the population level when nearly a billion people are projected to have high myopia by mid-century.
The economic toll is already substantial. In 2015, the global productivity loss from uncorrected myopia alone was estimated at $244 billion. That figure accounts for people who need glasses or contacts but don’t have access to them, a problem concentrated in lower-income countries but present everywhere.
Who Develops Myopia and When
Myopia typically develops in school-age children, most commonly between ages 6 and 14, when the eye is still growing. It tends to worsen through the teenage years before stabilizing in the early to mid-twenties for most people. The younger a child is when myopia first appears, the more time the eye has to continue elongating, and the higher the final prescription tends to be. A child diagnosed at age 7 is more likely to progress to high myopia than one diagnosed at 13.
This is why the trend toward earlier and more widespread onset is concerning. It’s not just that more children are becoming nearsighted. They’re becoming nearsighted younger, giving the condition more years to progress before the eye stops growing. The practical takeaway for parents: regular eye exams starting in early childhood can catch myopia early, and spending at least one to two hours outside each day during childhood is one of the most evidence-supported ways to reduce the chances it develops in the first place.