Robin Agpoon, an optometrist at Grene Vision Group, is in the business of eye health, so she knows sunglasses are more than a fashion statement.
"Especially in sunny Kansas," she says, they're essential to keeping eyes protected from the sun's ultraviolet A and ultraviolet B rays. That UVA and UVB light can damage your vision, sometimes permanently.
Agpoon has three pairs of sunglasses and is never without her polarized pair when driving.
Whether you're looking for the latest in fashion or the cheapest pair at the convenience store, consider Agpoon's advice on choosing.
You'll be doing your eyes a favor.
When to wear them
Anytime you're exposed to ultraviolet light, your eyes need protection. That pretty much means whenever you're outside, even in winter, even on an overcast day and even when you're in a car.
Children should wear sunglasses, too. It's difficult to keep sunglasses on a baby or toddler, so protect their eyes with a hat or the cover of a stroller.
What to look for
Polycarbonate lenses. They're shatter-resistant, making them perfect for children as well as for adults, even nonathletes -- what would happen to your eyes if you were in a car accident?
Ultraviolet protection. If they're not labeled as 100 percent UVA/UVB protective, they probably aren't.
Polarized lenses. If you're boating, skiing, even driving on a sunny day, polarized lenses will reduce glare.
Sports-specific sunglasses if you're an athlete.
Wraparound styles if you are exposed to a lot of ultraviolet light, such as on the water or on the ski slope. Some even have a little rim at the top that extends toward your face. When choosing, make sure your peripheral vision isn't hindered.
Is cheap OK?
You might be able to find a fashionable pair of sunglasses on the sale rack at the discount store, and that's just fine -- as long as they're labeled UVA/UVB protective. A couple of cautions: They may not be great optically, so you may get a magnification effect or some other distortion. Plus, the lenses probably aren't shatterproof. But they are protective.
In a similar vein, some fashion sunglasses are pretty small. But they are better than nothing.
Does color matter?
Lens color is a matter of personal preference. And darker doesn't mean better: Some photochromic (color-changing) lenses that are 100 percent UVA/UVB protective aren't very dark at all -- but are very good.
Here is a look at what different colors do:
Gray: Keeps surroundings true to color.
Amber or brown: Enhances contrast.
Yellow: Brightens surroundings. Good for overcast days.
Rose: Makes colors look more vivid and more attractive.
Mirrored: Great for sports, because opponents can't see your eyes or anticipate your next move. Law enforcement officials wear them for the same reason.
4 reasons to wear them
1. Ultraviolet rays can contribute to cataract formation. Everyone gets them eventually -- but eye doctors now are seeing cataracts in people who are in their 40s and 50s.
2. Your cornea can get sunburned, and that's painful. Burning your cornea puts you at increased risk of developing corneal degeneration.
3. You can get tissue overgrowth in your eye that causes vision distortion -- and looks unsightly.
4. Ultraviolet light may hasten the onset of macular degeneration.