Of the five senses, we tend to rely on sight the most. So it's no wonder that rumors persist over whether eating carrots will help you see better or if wearing glasses will actually make your vision worse. Curious about what really will or won't affect your sight? Here, we separate vision fact from fiction.
#1: Wearing contact lenses too long can make you go blind.
True: Wearing contact lenses for too long can cause protein to build up on the surface of the eyeball, which can block oxygen circulation to the eye. Common problems that can result from leaving contacts in for too long include corneal ulcers, bacterial or fungal infections, and irritation caused by oxygen deprivation. These can all lead to complications that can cause blindness. How to avoid these peeper problems? "Always change your contacts as indicated on the box," advises Michael Kutryb, MD, an ophthalmologist in private practice in Florida and a contributing expert in MedHelp's eye care forum. "Some contacts are for a single-day use, while others can last up to two weeks." Also, swimming with contacts is not a good idea because bacteria and microorganisms living in ponds, rivers and even some pools can get into the eye and lead to infections.
#2: Wearing glasses will slowly weaken your vision.
False: Glasses don't weaken your vision over time. The eyes naturally change throughout one's lifespan, and glasses have no effect on that process. "The eyes reach visual maturity at around six to seven years of age," says John C. Hagan III, MD, FACS, an ophthalmologist in Kansas City, Missouri, and a contributing expert in MedHelp's eye care forum. "If you don't correct your vision before a certain critical period, there's not much you can do aside from upkeep." However, people can still trick themselves into thinking otherwise. "Psychological dependence is another thing," says Dr. Hagan. "If people get used to wearing glasses, oftentimes they feel like they can't function without them. This can lead to the idea that depending on glasses or other visual aids will only degrade their eyes, which is completely false."
#3: Working in front of a computer or watching tv too often will damage your eyes.
False: We've all heard this one. "If this were true, we'd all be blind by now," says Dr. Hagan. "The only thing happening here is that our eyes get strained and tired." Viewing a television or computer monitor reduces the amount of times a person blinks, leaving the eyes dry and more prone to irritation and fatigue. "The number one thing that aggravates eyes are having dry eyes," says Dr. Kutryb. Of the two, computers are the worse offenders. "Staring at and focusing on a computer monitor is actually far more taxing on the eyes than watching TV," says Dr. Kutryb.
#4: Wearing sunglasses will protect your vision.
True: But only if the sunglasses have the proper protection. "People don't realize how damaging UV radiation can be," says Dr. Kutryb. Overexposure to UV rays damages the lens of the eye and may play a role in developing cataracts. Too much UV exposure can also damage the eye's retina, the light-sensitive lining at the back of the eye. UV rays can also reflect off surfaces to cause damage to the cornea. For instance, if you spend too much time in the snow on a sunny day without eye protection, you may experience snowblindness, where your cornea gets burned, leaving you in pain or even temporarily blind. Getting the right pair of sunglasses is crucial protection. "They should be polarized and protect against both UV-A and UV-B rays," explains Dr. Kutryb. Wearing shades that are merely tinted harm you more than they help you. The tint causes pupils to get larger, allowing more unfiltered UV rays to get into the eyes.
False: Glasses don't weaken your vision over time. The eyes naturally change throughout one's lifespan, and glasses have no effect on that process. "The eyes reach visual maturity at around six to seven years of age," says John C. Hagan III, MD, FACS, an ophthalmologist in Kansas City, Missouri, and a contributing expert in MedHelp's eye care forum. "If you don't correct your vision before a certain critical period, there's not much you can do aside from upkeep." However, people can still trick themselves into thinking otherwise. "Psychological dependence is another thing," says Dr. Hagan. "If people get used to wearing glasses, oftentimes they feel like they can't function without them. This can lead to the idea that depending on glasses or other visual aids will only degrade their eyes, which is completely false."
#3: Working in front of a computer or watching tv too often will damage your eyes.
False: We've all heard this one. "If this were true, we'd all be blind by now," says Dr. Hagan. "The only thing happening here is that our eyes get strained and tired." Viewing a television or computer monitor reduces the amount of times a person blinks, leaving the eyes dry and more prone to irritation and fatigue. "The number one thing that aggravates eyes are having dry eyes," says Dr. Kutryb. Of the two, computers are the worse offenders. "Staring at and focusing on a computer monitor is actually far more taxing on the eyes than watching TV," says Dr. Kutryb.
#4: Wearing sunglasses will protect your vision.
True: But only if the sunglasses have the proper protection. "People don't realize how damaging UV radiation can be," says Dr. Kutryb. Overexposure to UV rays damages the lens of the eye and may play a role in developing cataracts. Too much UV exposure can also damage the eye's retina, the light-sensitive lining at the back of the eye. UV rays can also reflect off surfaces to cause damage to the cornea. For instance, if you spend too much time in the snow on a sunny day without eye protection, you may experience snowblindness, where your cornea gets burned, leaving you in pain or even temporarily blind. Getting the right pair of sunglasses is crucial protection. "They should be polarized and protect against both UV-A and UV-B rays," explains Dr. Kutryb. Wearing shades that are merely tinted harm you more than they help you. The tint causes pupils to get larger, allowing more unfiltered UV rays to get into the eyes.
#5: Certain types of light are better for your eyes than others.
False: People seem to be sensitive to certain types of lighting. Some claim that working under fluorescent lighting gives them eyestrain and headaches. Others claim that natural lighting is poor for reading. This is mostly based off of preference, as some people like more light and some like less. But it's very unlikely that people will have a real positive or negative physiological reaction to light, according to Dr. Hagan.
#6: Having a night-light on for infants or toddlers will make them near-sighted.
False: "This rumor was pretty controversial," says Dr. Kutryb. In the May 13, 1999 issue of the medical journal, Nature, University of Pennsylvania researchers raised concerns that the use of a night-light in the rooms of infants will make them five times more likely to develop myopia (near-sightedness) than infants left in a dark room. However, this notion has since been debunked thanks to a study in the May 2001 edition of Investigative Opthalmology and Visual Science. Scientists at Yerkes National Primate Research Center at Emory University and the College of Optometry at the University of Houston assert that constant light does not cause near-sightedness in infants. There are many factors involved with vision development that children inherit, and some that are involved with how their eyes acclimate to their surroundings during the critical years of development. However, night-lights don't contribute to any vision problems, including near-sightedness.
#7: Anyone can benefit from Lasik eye surgery.
False: Lasik eye surgery, a type of vision correction procedure that uses specialized lasers to change the shape of the cornea, is only capable of correcting deficits in vision that are correctable with glasses. "If somebody has reduced vision due to macular degeneration (damage to the center of the pupil, an area critical for directing where the eyes should focus), detached retina, glaucoma or because of some other eye disease, Lasik won't do a thing," says Dr. Hagan. If a patient does qualify for Lasik treatment, usually vision can be corrected to 20/20 in only one session, though follow-up fine-tuning, called "enhancements," are necessary on occasion. Sometimes, the shape of a person's eye precludes them from Lasik. "We have patients with poor eye curvatures, and treating them with Lasik would not benefit them one bit," says Dr. Hagan.
#8: Carrots are good for your vision.
False: "Carrots are not the magic food for your eyes," says Dr. Hagan. "If I had to pick one magic food, eat spinach." While carrots are rich in beta-carotene, a precursor to vitamin A, most people are not deficient in beta-carotene; it's a nutrient that many foods (fortified, or not) have. "I'd rather people get more lutein," says Dr. Hagan. Lutein, a nutrient abundant in spinach, is a chemical substance that is important to macular health. Most Americans are lutein-deficient. The human body cannot make lutein (it also gets harder to absorb it as you age), so sufficient levels depend on diet. Other dark-colored veggies like asparagus and broccoli are also great natural source of lutein, as are cooked tomatoes and cooked tomato products like pasta sauce. You can also purchase multivitamins containing lutein, but many don't contain the recommended daily amount (6 mg), so be wary.
#9: 20/20 score is the best possible score you can get.
False: "Visual acuity is distributed like a typical bell shaped curve," says Dr. Hagan. "20/20 is at the top of the curve. But there are people on both sides of that." It is not unusual for people to have vision better than 20/20. Some are blessed with 20/15 and 20/10. Those are the pairs of eyes that the Air Force is looking for!
False: People seem to be sensitive to certain types of lighting. Some claim that working under fluorescent lighting gives them eyestrain and headaches. Others claim that natural lighting is poor for reading. This is mostly based off of preference, as some people like more light and some like less. But it's very unlikely that people will have a real positive or negative physiological reaction to light, according to Dr. Hagan.
#6: Having a night-light on for infants or toddlers will make them near-sighted.
False: "This rumor was pretty controversial," says Dr. Kutryb. In the May 13, 1999 issue of the medical journal, Nature, University of Pennsylvania researchers raised concerns that the use of a night-light in the rooms of infants will make them five times more likely to develop myopia (near-sightedness) than infants left in a dark room. However, this notion has since been debunked thanks to a study in the May 2001 edition of Investigative Opthalmology and Visual Science. Scientists at Yerkes National Primate Research Center at Emory University and the College of Optometry at the University of Houston assert that constant light does not cause near-sightedness in infants. There are many factors involved with vision development that children inherit, and some that are involved with how their eyes acclimate to their surroundings during the critical years of development. However, night-lights don't contribute to any vision problems, including near-sightedness.
#7: Anyone can benefit from Lasik eye surgery.
False: Lasik eye surgery, a type of vision correction procedure that uses specialized lasers to change the shape of the cornea, is only capable of correcting deficits in vision that are correctable with glasses. "If somebody has reduced vision due to macular degeneration (damage to the center of the pupil, an area critical for directing where the eyes should focus), detached retina, glaucoma or because of some other eye disease, Lasik won't do a thing," says Dr. Hagan. If a patient does qualify for Lasik treatment, usually vision can be corrected to 20/20 in only one session, though follow-up fine-tuning, called "enhancements," are necessary on occasion. Sometimes, the shape of a person's eye precludes them from Lasik. "We have patients with poor eye curvatures, and treating them with Lasik would not benefit them one bit," says Dr. Hagan.
#8: Carrots are good for your vision.
False: "Carrots are not the magic food for your eyes," says Dr. Hagan. "If I had to pick one magic food, eat spinach." While carrots are rich in beta-carotene, a precursor to vitamin A, most people are not deficient in beta-carotene; it's a nutrient that many foods (fortified, or not) have. "I'd rather people get more lutein," says Dr. Hagan. Lutein, a nutrient abundant in spinach, is a chemical substance that is important to macular health. Most Americans are lutein-deficient. The human body cannot make lutein (it also gets harder to absorb it as you age), so sufficient levels depend on diet. Other dark-colored veggies like asparagus and broccoli are also great natural source of lutein, as are cooked tomatoes and cooked tomato products like pasta sauce. You can also purchase multivitamins containing lutein, but many don't contain the recommended daily amount (6 mg), so be wary.
#9: 20/20 score is the best possible score you can get.
False: "Visual acuity is distributed like a typical bell shaped curve," says Dr. Hagan. "20/20 is at the top of the curve. But there are people on both sides of that." It is not unusual for people to have vision better than 20/20. Some are blessed with 20/15 and 20/10. Those are the pairs of eyes that the Air Force is looking for!
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