In 1972, approximately 25% of Americans were myopic. Today, that figure exceeds 42% — and the trend shows no sign of reversing. In East Asian countries, the numbers are far more striking: prevalence rates among young adults in Singapore, South Korea, Taiwan, and urban China now exceed 80-90%. Global projections suggest that by 2050, nearly five billion people — roughly half the world’s population — will be myopic, with approximately one billion experiencing high myopia.
This is not primarily a genetic story. Human genetics cannot shift this dramatically in two or three generations. The myopia epidemic is an environmental and behavioral phenomenon, and understanding it has direct implications for public health, parenting decisions, and vision correction planning.
This guide is part of the Eye Health and Vision Care resource. It covers the epidemiology of the epidemic, the leading causal hypotheses, the clinical distinction between myopia as a refractive inconvenience and myopia as a disease risk, and what can be done — both for individual children and at a population level.
The Epidemiology: How Bad Is It?
The prevalence data on myopia is unambiguous. In studies following urban Asian populations from the 1970s to the present, myopia prevalence among young adults has roughly tripled. In some East Asian cities, it is now extraordinary: a 2012 study in Seoul, South Korea found that 96.5% of 19-year-old male conscripts were myopic.
In the United States and Europe, the increases are less dramatic but still substantial. The roughly doubling of U.S. prevalence over fifty years — from 25% to 42% — represents tens of millions of additional people who require vision correction.
Age of onset has also shifted earlier. Earlier onset myopia predicts greater final prescription magnitude, because the eye has more developmental years in which to elongate. A child who becomes myopic at age 7 will likely reach a higher final prescription than one who becomes myopic at 14.
The clinical significance of this trend extends well beyond the inconvenience of needing glasses. A significant proportion of the newly myopic will progress to high myopia (above -6.00 D), and high myopia is associated with serious and potentially blinding complications.
What Causes the Myopia Epidemic?
The leading hypotheses are not mutually exclusive. Most researchers believe the epidemic is multifactorial, with two dominant environmental drivers: reduced time outdoors and increased near-work demand.
The outdoor light hypothesis: This is currently the best-supported explanation. Studies across Asia, Australia, and Europe consistently find that children who spend more time outdoors develop myopia at lower rates and progress more slowly when they do develop it. A landmark randomized controlled trial in Taiwan added ninety minutes of outdoor time per day to primary school schedules and found a significant reduction in myopia onset compared to control schools.
The mechanism appears to involve light intensity and dopamine. Bright outdoor light — even on a cloudy day, typically 10,000-100,000 lux — stimulates dopamine release in the retina. Dopamine, in turn, appears to inhibit axial elongation of the eyeball. Indoor light, even in a well-lit room, rarely exceeds 500 lux — far below the threshold to trigger this protective mechanism.
This is not about what children look at outdoors — simply being in bright light, regardless of near or distance activity, appears to be protective. It is the light intensity, not the viewing distance per se, that matters.
Near-work demand: Extended time spent focusing on objects at close range — reading, writing, digital screens — has long been hypothesized to promote myopia. The mechanism proposed is that sustained accommodation (the ciliary muscle contracting to focus on near objects) sends signals that promote axial elongation. Some studies support this association; others find it difficult to separate from the correlated reduction in outdoor time. The two often co-occur — a child reading indoors is simultaneously not being outdoors.
Genetic predisposition: Genetics unquestionably plays a role in individual susceptibility. Having two myopic parents approximately six-fold increases a child’s risk compared to having no myopic parents. Genome-wide association studies have identified hundreds of genetic variants associated with myopia susceptibility. But these genetic risk factors have not changed in two to three generations — which is why they cannot explain the epidemic. Genetics sets the susceptibility; environment determines whether that susceptibility is expressed.
High Myopia: Beyond a Refractive Inconvenience
The vision correction community — and the public — often treats myopia as a problem of inconvenience: you need thick glasses or contacts to see. For mild to moderate myopia, that framing is largely accurate. For high myopia (above -6.00 D), it significantly underestimates the clinical stakes.
A highly myopic eye is physically longer than normal. The retina, choroid, and sclera are stretched to accommodate this elongation. Over decades, this stretch produces structural vulnerability:
Retinal detachment: The stretched retina is thinner and more prone to developing peripheral holes or tears, which can progress to retinal detachment. The lifetime risk of retinal detachment is approximately 0.06% in the general population. In patients with myopia above -6.00 D, it rises to approximately 3% — a fifty-fold increase.
Myopic maculopathy: Progressive degeneration of the central retina (macula) in highly myopic eyes. Can cause significant and irreversible central vision loss. The risk increases substantially with prescription severity.
Glaucoma: Highly myopic eyes have higher rates of glaucoma, potentially because optic nerve anatomy in elongated eyes makes them more vulnerable to pressure-related damage.
Cataracts: High myopes develop cataracts earlier than the general population.
These risks do not disappear with laser vision correction. LASIK or PRK changes the optical system — it does not shorten the eye or restore normal retinal architecture. A patient with -9.00 of myopia who undergoes successful LASIK still has a highly myopic eye structure and retains the elevated retinal detachment risk. This is a critical point that surgeons should communicate clearly, and that patients should understand. See understanding your eye prescription for more on what high sphere values mean.
Myopia Management: Slowing Progression in Children
The emergence of evidence-based myopia management has been one of the most significant developments in optometry and ophthalmology over the past decade. Several interventions have demonstrated meaningful efficacy in slowing myopia progression in children:
Atropine drops: Low-dose atropine (0.01-0.05%) applied nightly has demonstrated robust evidence for slowing myopia progression with minimal side effects in multiple large randomized trials. Mechanism is not fully understood but is believed to involve retinal dopamine pathways.
Orthokeratology (Ortho-K): Rigid gas-permeable contact lenses worn overnight that temporarily reshape the cornea, providing clear vision during the day without lenses. Multiple studies have demonstrated 40-60% slowing of axial elongation with regular use.
Specialized soft contact lenses: Multifocal and defocus-incorporating soft lenses (e.g., MiSight) have been approved for myopia management and shown efficacy in randomized trials.
Outdoor time: The simplest and safest intervention — increasing daily outdoor time to at least 90-120 minutes. Supported by randomized evidence and appropriate for all children regardless of myopia status.
These interventions are typically recommended for children who show early myopia onset, rapid progression, or high predicted final prescriptions. Parents who have myopic children should proactively ask their eye care provider about myopia management — it is not universally offered without explicit discussion. See eye health by age for age-appropriate guidance.
Implications for Adults Considering Vision Correction
For adults with myopia considering surgical correction, the epidemic context matters in two ways. First, adults who developed myopia early and progressed rapidly should expect careful screening for high-myopia-related corneal changes before laser surgery. Second, adults with high myopia should understand that EVO ICL or refractive lens exchange may be preferred over laser ablation, both because they extend the treatable prescription range and because they do not further thin the cornea.
The LASIK Surgery Awards recognize surgeons who demonstrate excellence in complex myopia cases, including high myopia management and appropriate procedure selection.
Related Pages
- Eye Health and Vision Care — Complete hub overview
- Common Vision Problems and Their Causes — Understanding myopia as a refractive error
- Corneal Health and Vision Correction — Implications of high myopia for surgical candidacy
- Eye Health by Age — School-age myopia onset and management
Frequently asked questions:
- Is Nearsightedness Genetic?
- Why Is My Vision Getting Worse Every Year?
- Can Screen Time Make My Vision Worse?
- At What Age Does Vision Start to Decline?
*All content is for educational purposes. Consult a qualified eye care professional for myopia management recommendations for you or your child.*