By 2040, it’s estimated that more than 50 percent of U.S. children and adults will be myopic or “nearsighted”, according to a paper in the Journal of Ophthalmology. With prevalence already rising globally, this condition has emerged as a major health issue that demands attention. Last September, the National Academies of Sciences (NAS) released a milestone report on myopia. “Recognition of the impact of its downstream complications on people’s lives beyond nearsightedness needs to be taken seriously,” said K. Frick, a health economist and professor at Johns Hopkins University School of Medicine and co-chair of the committee that wrote the report.

Myopia results in blurry long-distance vision. A person with myopia can see clearly up close, such as when reading a book or phone screen, while distant objects like street signs or landscape details appear blurry and difficult to read. Myopia is typically discovered during regular eye exams or when parents notice their child squinting to see objects far away, such as street signs or classroom boards. In children, myopia progresses most rapidly between ages 8 and 12, then slows into the teen and young adult years. The progression rate varies, but typically ranges from -0.25 to -1 diopter per year. For children diagnosed between ages 3 and 6, progression is closely monitored, as myopia is considered high when it reaches -5 diopters or more.

Our current lifestyles are increasingly more urban, with people spending more time on indoor activities and using digital devices for a broad range of activities over the course of a day. Thirty years ago, it was uncommon for young adults to be diagnosed, but that trend has shifted. Myopia progression is now increasingly seen in people in their 20s and 30s while navigating college, graduate school and early careers.

Eye doctors care about progression rates because, as myopia worsens, individuals are at greater risk for sight-threatening diseases later in life. In 2012, these risks were quantified in a paper published in Progress in Eye and Retinal Research that found retinal detachments are three times more likely in individuals with low levels of myopia, but the risk rises significantly for prescriptions greater than -3 diopters. For those with prescriptions reaching -5 diopters and greater, the risk increases 20 times. Myopic maculopathy, or myopic macular degeneration, is nearly 10 times more likely in individuals with prescriptions between -3 and -5 diopters, with the risk escalating 40 times for those with -5 diopters or higher. Without intervention, there will be serious long-term implications not only for individuals today but for generations to come.

While standard glasses or contacts do address current visual deficiencies and help children and young adults navigate their environment more effectively, they don’t address the known risk factors associated with a myopia diagnosis and its progression. Parents and eye doctors must play an important role in helping to make children and young adults aware of the importance of building healthy visual habits from an early age.

Excessive close-up activities such as reading, writing and screen time also increase the likelihood of myopia progression. A lack of outdoor activity, particularly with less than 120 minutes spent outside per day, is another significant risk factor which was highlighted as a key recommendation in the NAS report on myopia. Genetics also plays a role, as children are more likely to develop myopia if one or both parents have the condition.

Building good visual habits is essential for visual health. Taking regular breaks is one important practice—during reading, screen time or homework, it’s helpful to take a two-to-three-minute break every 30 minutes. This can involve standing up, stretching, or stepping outside for fresh air to give the eyes a rest. Good lighting, particularly natural light, along with proper posture, helps prevent eye strain during near work. Limiting phone screen time is another key habit to actively manage. In the U.S., children ages 8 to 12 typically spend four to six hours per day on screens, so reducing this by 50 percent, or about two hours per day, can be beneficial. Swapping screen time for outdoor activities further supports eye health. Spending at least 120 minutes outdoors each day—whether through biking, playing catch, or simply walking or running—can help prevent myopia. If needed, this time can be broken into smaller increments throughout the day.

If a child or individual experiences difficulty seeing distant objects and is exhibiting signs of squinting or blurry vision, it is important that they visit an eye doctor. Vision problems can affect academic performance, behavior and overall well-being, and regular eye exams are essential for monitoring eye health. If myopia is diagnosed, myopia control programs may be available to help slow progression. Addressing the risks and implementing healthy habits can help reduce the impact of myopia and its long-term effects on vision.