Updated on September 24, 2024.
There are many causes of myopia (that is, being nearsighted), but some research suggests that it may be linked to doing too much near work.
A 2023 review published in the International Journal of Environmental Research & Public Health looked at 78 studies, and concluded that near work, or activities that require looking at things up close (like books), may be linked to myopia.
Why this link? There are likely a combination of reasons.
Not enough outdoor time. One reason may be that up-close activities like reading tend to be indoors, so people focusing on studying may get less outdoor exposure, which may affect their vision. Past studies have looked at both the number of kids with myopia and the speed at which it can worsen, and found that being outdoors (for example, in the summer, when kids are out of school) is linked to less and slower-progressing myopia.
So what is it about being outdoors that’s helpful? A 2020 review published in the British Journal of Ophthalmology looked at many reasons why going outside might help people of all ages with eye health. Researchers found that one major protective part of outdoor activities could be the exposure to bright light.
Too much screen time. Staring at a computer screen likely plays a part in the development or worsening of myopia, but more research needs to be done to pin down how and why. A 2020 review in the journal Ophthalmic & Physiological Optics found mixed results—about half of the 15 studies examined showed a link between myopia and screen time.
And a 2021 review and meta-analysis published in the journal Lancet Digital Health looked at a total of 44 studies on the use of devices like smartphones and tablets and concluded that better, more reliable research is still needed to really give an accurate picture of the link. One issue was that a lot of the studies relied on participants self-reporting how much time they spend on devices, and that can be easy to underestimate.
Ways to protect your eyesight
The evidence is mounting that changes in our lifestyles have led to more time spent indoors, increased reading, and higher use of technology—all of which may have contributed to the increasing rates of myopia. And while focusing on education is encouraged, so is protecting your vision.
Your risk of nearsightedness also has a lot to do with your genes, but there are things you can do to help avoid it. Check out these five tips to protect your vision:
Spend more time outside. Researchers have found that a lack of sunlight may contribute to nearsightedness – and that 120 minutes a day of exposure may help reduce your risk for it. Consider soaking up some sunshine during your study breaks or exercising outside to get your daily dose of fresh air. Be sure to use proper sun and insect protection while you’re out and about.
Take breaks from near work. The Centers for Disease Control and Prevention (CDC) recommends what they call the “20-20-20 rule” for preventing eye strain related to near work, such as using a computer or reading a book. Next time you’re doing near work, take a break every 20 minutes and focus your eyesight on something 20 feet away for 20 seconds.
Eat healthy. To keep your vision strong, eat a healthy diet rich in fresh fruits, vegetables, lean protein, and whole grains. Limit refined carbohydrates and foods with added sugars. These raise insulin levels, which may affect eyesight. Try to include foods that are good for your eyes. Orange-colored fruits or veggies tend to be high in vitamin A, an important nutrient for eyes—try sweet carrots, potatoes, cantaloupe, and apricots. Foods containing vitamin C, vitamin E, and omega-3 fatty acids are also winners, so snack on oranges, red bell peppers, avocados, almonds, and cold-water fish, like salmon and tuna. And don’t forget about dark leafy greens—they’re high in antioxidants that help lower inflammation and keep your body healthy.
Try contacts. Several past and recent studies suggest that, for some people, swapping out glasses for contacts—especially multifocal soft contact lenses—may actually slow the progression of nearsightedness. So if you’ve always worn glasses, try seeing if the switch to contacts is right for you.
Be sure to consider other possible causes, too. For example, nearsightedness may be a sign of blood sugar problems (which can lead to diabetes). Talk to an optometrist or ophthalmologist if you start experiencing any myopia symptoms to determine what may be causing your vision problems.
