Sunglasses in winter? Ultraviolet’s not so hot

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Sunglasses in winter? Ultraviolet’s not so hot

As far as eyes go, the digital era is the worst period yet seen. Eyes quickly tire from surfing the Internet or playing computer games, and as a result one’s vision deteriorates, sometimes temporarily, but sometimes permanently. In the latter case, the person has to use prescription spectacles. According to the Korean Optometry Association, as of last year one in every two Korean adults had to wear glasses.
Eyes are one of the few organs that are exposed to the elements, and for that reason can easily be damaged. People, it seems, have to keep a watchful eye on their eyes. The good news is that by changing one’s daily habits and altering one’s routine a little, a person can keep his or her eyes in good condition.
When reading a book, working on a computer or watching television, your eyes need to be rested for at least 10 minutes for every 50 minutes of use. The five-to-one ratio is called the “golden ratio,” as it’s much better for your eyes than continuous use during concentration on a task and then taking a longer break.
“Focusing on a computer monitor or reading a book for a long time can cause false myopia,” says Kim Hee-young, an ophthalmologist at Hallym Medical Center. “After working on a computer, massage the temples slightly with the first, second and third fingers, and look out of a window at distant scenery ― green if possible ― as this also helps.” The color green helps the eyes to relax and minimizes fatigue. That’s why school blackboards these days are actually green.
“Some people just turn on a desk lamp while turning off the lights in the entire room in order to increase their concentration,” said Kim Yong-ran, a professor of the ophthalmology department at Konyang University. “That’s very bad for the eyes. People experience more fatigue when the contrast between light and dark is stronger.”
Workplaces should be kept bright. When reading books or working on computers under a very dark light, your eyes easily feel fatigue and your concentration drops. Research has shown that the sight of mice raised in a bright area was better than that of mice raised in the dark. Don’t go overboard, though: too much bright light can be equally bad. It’s best to have light from 600 lux (a unit of measurement for brightness) to 1,000 lux.
To protect your eyes, sunglasses are a must, even in winter. Some consider sunglasses to be a summer-only item, but a person’s eyes are still exposed to ultraviolet radiation in winter. The ultraviolet rays reflected off snow or snowfields at ski resorts are actually more dangerous than the rays from the summer sun.
The common belief that Koreans are resistant to ultraviolet rays is wrong. Koreans may feel less blinded by strong sunlight than Westerners because their pupils are darker and absorb more light.
Long exposure to ultraviolet rays can prematurely age a person’s eyes. Eyes that are hit by ultraviolet radiation accumulate free radicals that can cause serious conditions, such as cataracts and macular degeneration. People who already have these conditions or who are taking medicine that is sensitive to light, such as doxycycline, should not expose themselves to ultraviolet rays.
“A person could develop cataracts and even keratitis [inflammation of the cornea] when they are still young if they wander around ski resorts or in the snow without wearing sunglasses or goggles,” says Park In-gee, an ophthalmologist at Kyung Hee University Medical Center. “If the weather gets warmer and the sun gets stronger, a person should wear a hat, use a sunshade and wear sunglasses.”
Lee Jeong-soo, the head of nutrition at Myongji Hospital, says that vitamin A is the most important vitamin for healthy eyes. The vitamin can be found in liver, tomatoes, sweet potatoes, spinach, seafood and parsley. “A lack of vitamin A can cause night blindness or corneal xerosis [drying].”
Vitamin B complex is also important for the eyes. A lack of vitamin B1 causes weakness in the optic nerve ― a lack of B2 causes cloudiness of the cornea, the rupturing of micro blood vessels and in the long term can lead to cataracts. Vitamin B complex is abundant in peanuts, raw oyster, milk, liver and pork.
Recently, doctors have been recommending that people stock up on beta-carotene and vitamins C and E, as these assist in the removal of free radicals that accumulate around the eyes.
It’s also good to wash your eyes at least once a day with warm water. Don’t forget to massage around the eyes with your fingers while you do so ― this relieves soreness by pushing tears out of sebaceous glands at the corner of the eyes. People who wear contact lens should maintain the recommended change cycle ― this varies from one day, two weeks, one month to even a year. Joo Cheon-gee, an ophthalmologist at Kangnam St. Mary’s Hospital, says 30 percent of users of contact lenses have not changed lenses for more than a year, which he said could lead to serious problems in the future.

by Park Tae-kyun
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