Outdoor time may reduce risk of nearsightedness – but wear sunglasses!New studies show natural light may be essential for normal eye development in kids and for maintaining healthy body rhythms as we age.
New studies show natural light may be essential for normal eye development in kids and for maintaining healthy body rhythms as we age.
According to the sun, it’s about time it got credit for something.
A major eye research journal reports strong evidence that spending about three hours per day outdoors is important for lowering the risk of nearsightedness in school-age children and young adults. Natural light apparently stimulates a chemical called dopamine in the eye, which regulates normal growth of the eyeball. This is important because when an eye grows too long (as measured from front to back), it cannot properly focus images on the retina, and nearsightedness develops.
Minnesota ophthalmologists (Eye M.D.s) recommend Minnesotans enjoy outdoor time and plenty of natural light--with the appropriate sunglasses. That’s because plenty of other studies have shown bright sunlight may increase the risk of developing cataracts, age-related macular degeneration and growths on the eye, including cancer.
Elders Need More Natural Light, Are Getting Less
Research exploring the interactions of light exposure, cataract development and older people's health shows that elders may have both a higher need for natural light and a harder time getting it than do younger people. A part of the natural light spectrum, called blue light, is important for our ability to maintain healthy bodily rhythms, also called circadian rhythms or biorhythms.
When the lens in the back of the eye ages, it gradually losses the ability to absorb blue light. When the brain receives less blue light, it produces less melatonin, a substance that regulates sleep-wake cycles. This increases the risk of insomnia and other sleep problems, which can be factors in serious conditions like depression and heart disease. Other studies have shown that when older people have their clouded lenses replaced in cataract surgery, their sleep, mood, and thinking processes improve as well as their eyesight.
Specific recommendations on how cataract surgery, exposure to natural light, and other methods could be used to support older peoples' health should be available soon from medical scientists.
In the meantime, add more natural light to your day if possible, and follow these tips to protect your eyes from the UV rays:
• Make sure your sunglasses block 100 percent of UVA and UVB rays.
• Ideally, your sunglasses should wrap all the way around to your temples, so the sun's rays can't sneak in from the side.
• Wear a hat in addition to your sunglasses. Broad-brimmed styles provide the best protection for your eyes.
• Even if your contact lenses have UV protection, wear your sunglasses.
• Don't be fooled by clouds: the sun's rays can pass through haze and thin clouds. Sun damage to eyes can occur anytime during the year, not just in the summertime—so be sure to wear sunglasses whenever you're outside.
• Looking directly at the sun, including during an eclipse, can lead to solar retinopathy, which is damage to the eye's retina from solar radiation. Don’t ever look directly at the sun.
The Minnesota Academy of Ophthalmology invites Minnesotans to visit www.MNEyeMD.org for accurate eye health and eye disease information.