By Shine-Ning Ni
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.
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.
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. "Psychological dependence is another thing. 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."
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.
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.
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