Light is essential to provide us with good visual acuity. It helps us see contrast, perceive colors, and helps with non-visual functions such as regulating our sleep/wake cycle. This in turn allows us to maintain and regulate memory, mood, and hormone balance.
Light can also be damaging to our body and our eyes. UV radiation can damage your skin by causing sunburn and skin cancers such as basal cell carcinoma, squamous cell carcinoma and melanoma. UV radiation also harms your eyes in multiple ways. UV light is a contributing factor to the formation of cataracts, macular degeneration, pingueculae, pterygia and photokeratitis.
Although you cannot see UV radiation, it is there, just as is the warmth you can feel and the bright light you can see coming from the sun. While many people remember to wear sunglasses on trips to the beach or while watching a baseball game on a sunny afternoon, sunglasses should be worn outdoors during all months of the year. You may be surprised to know that fresh snow can reflect 88% of UV rays, almost doubling your overall exposure!
Types of UV Rays
There are three categories of invisible, high-energy UV rays, they are described below:
UVC
• UVC rays are the highest energy rays and potentially the most harmful to your eyes and skin. Luckily, the ozone layer blocks virtually all UVC rays, as long as we have an ozone layer.
UVB
• UVB rays are partially filtered by the ozone layer, but some still reach us here on Earth. UVB rays are thought to cause growths on the outside, white parts of the eye. These growths are known as pingueculae and pterygia. They can be the source of discomfort, corneal problems, and distorted vision. UVB rays can also cause photokeratitis, or “snow blindness,” which is a painful inflammation of the cornea that can cause vision loss for 24-48 hours. Snow blindness occurs most often at high altitudes, but can occur anywhere there is snow if UV-blocking sunglasses are not worn. UVB rays are responsible for stimulating melanin production, which creates a suntan. High doses can cause sunburn and increase the risk of skin cancer. UVB rays also cause wrinkles, discolorations of the skin, as well as other premature signs of aging.
UVA
• UVA rays are lower in energy than UVC and UVB rays; however UVA rays can pass through the front surface of the eye, the cornea, and reach the lens and retina inside the eye. UVA rays are the least damaging to the eye, but they may be linked to certain types of cataracts, and they may also play a role in macular degeneration development.
Risk Factors
Geographic location – tropical areas near the equator have the greatest levels of UV radiation.
Altitude – UV levels are greater at higher altitudes due to a thinner atmosphere filtering out less UV radiation. Something to keep in mind for climbers and trail hikers: for every 1,000 feet ascended in altitude, there is a 5-7% increase in UV radiation!
Time of Day – UV radiation is greatest when the sun is high in the sky, but this can change with the seasons. During the summer the highest level of UV exposure is typically between 10 a.m. to 2 p.m. During the winter this is between 8 a.m. and 10 p.m. and between 2 p.m. and 4 p.m.
Setting – Greater UV levels are found in wide open spaces with highly reflective surfaces, such as snow and sand. UV exposure nearly doubles when rays are reflected from the snow!
Medications – Tetracycline’s, sulfa drugs, birth control pills, diuretics and tranquilizers are examples of medications that increase your body’s sensitivity to UV and HEV radiation.
Cloud Cover – This has no significant effect on UV levels! UV radiation can penetrate clouds, and clouds can further scatter UV radiation to the Earth’s surface. UV exposure risk is still high and may actually be greater on hazy, overcast days!
Standing in the shade reduces your overhead UV and HEV exposure to some degree, but remember that UV rays are invisible and are being reflected off of buildings, roadways and other surfaces around you.
Here are examples of different surfaces and how much UVB radiation is reflected off of each:
• Fresh snow: 88%
• Dirty snow: 59%
• Sea foam (surf): 25-30%
• White house paint: 22%
• Dry sand: 15-18%
• Concrete pavement: 8-12%
• Wet sand: 7%
• Black asphalt: 4-9%
• Grass in winter: 3-5%
• Grass in summer: 2-4%
What To Look For In Sunglasses
• Look for sunglasses that block 100% of UV rays.
• Larger lenses provide greater protection to your eyes and the surrounding skin. In fact, 5-10% of all skin cancers occur in the eyelids, which is why this area requires protection as well.
• Wraparound styles also limit the radiation reaching your eyes from the periphery.
• If you wear contact lenses, invest in a pair of sunglasses that you can wear over your contact lenses. Also, ask your optometrist about which contact lens brands block UV radiation!
• If you wear glasses, ask your optometrist or optician about lens materials that inherently block 100% of UV radiation. In addition, prescription sunglasses ensure you’re comfortable in bright sunlight while also protecting your eyes from harmful, non-visible radiation.
• If the expense or inconvenience of a second pair of prescriptions sunglasses is an issue, look for fit-over or clip-on sunglasses. Both are 2-in-1 options designed to be worn over prescription frames.
• Depending on your lifestyle, sport or performance sunglasses may be a good option. For example, skiers and snowboarders should wear ski goggles with UV protection at all times while on the slopes.
• UV protection is not correlated to the color or darkness of the lenses, clear lens materials can block UV too!
Your optometrist and optician are happy to help you choose the best sunglasses for your needs!
Don't Forget The Kids!
After smearing your children with sunscreen, be sure to grab their UV blocking sunglasses before letting them out the door. Children tend to spend more time outside than most adults, increasing their UV exposure. The eye anatomy also makes them more susceptible to retinal damage from UVA rays. This is because the natural lens inside their eye is clearer than an adult lens, allowing more UV radiation to penetrate and reach the retina. Encourage your kids to wear quality sunglasses that block 100% of UV radiation, in addition to wearing a hat or visor while outdoors!
For more information about UV rays and the importance of sunglasses to your overall health, please contact us by calling 419-538-6273 or send us a website message.
Check out our latest special offers and opportunities to save on quality sunglasses by visiting this link: Special Offers
Light can also be damaging to our body and our eyes. UV radiation can damage your skin by causing sunburn and skin cancers such as basal cell carcinoma, squamous cell carcinoma and melanoma. UV radiation also harms your eyes in multiple ways. UV light is a contributing factor to the formation of cataracts, macular degeneration, pingueculae, pterygia and photokeratitis.
Although you cannot see UV radiation, it is there, just as is the warmth you can feel and the bright light you can see coming from the sun. While many people remember to wear sunglasses on trips to the beach or while watching a baseball game on a sunny afternoon, sunglasses should be worn outdoors during all months of the year. You may be surprised to know that fresh snow can reflect 88% of UV rays, almost doubling your overall exposure!
Types of UV Rays
There are three categories of invisible, high-energy UV rays, they are described below:
UVC
• UVC rays are the highest energy rays and potentially the most harmful to your eyes and skin. Luckily, the ozone layer blocks virtually all UVC rays, as long as we have an ozone layer.
UVB
• UVB rays are partially filtered by the ozone layer, but some still reach us here on Earth. UVB rays are thought to cause growths on the outside, white parts of the eye. These growths are known as pingueculae and pterygia. They can be the source of discomfort, corneal problems, and distorted vision. UVB rays can also cause photokeratitis, or “snow blindness,” which is a painful inflammation of the cornea that can cause vision loss for 24-48 hours. Snow blindness occurs most often at high altitudes, but can occur anywhere there is snow if UV-blocking sunglasses are not worn. UVB rays are responsible for stimulating melanin production, which creates a suntan. High doses can cause sunburn and increase the risk of skin cancer. UVB rays also cause wrinkles, discolorations of the skin, as well as other premature signs of aging.
UVA
• UVA rays are lower in energy than UVC and UVB rays; however UVA rays can pass through the front surface of the eye, the cornea, and reach the lens and retina inside the eye. UVA rays are the least damaging to the eye, but they may be linked to certain types of cataracts, and they may also play a role in macular degeneration development.
Risk Factors
Geographic location – tropical areas near the equator have the greatest levels of UV radiation.
Altitude – UV levels are greater at higher altitudes due to a thinner atmosphere filtering out less UV radiation. Something to keep in mind for climbers and trail hikers: for every 1,000 feet ascended in altitude, there is a 5-7% increase in UV radiation!
Time of Day – UV radiation is greatest when the sun is high in the sky, but this can change with the seasons. During the summer the highest level of UV exposure is typically between 10 a.m. to 2 p.m. During the winter this is between 8 a.m. and 10 p.m. and between 2 p.m. and 4 p.m.
Setting – Greater UV levels are found in wide open spaces with highly reflective surfaces, such as snow and sand. UV exposure nearly doubles when rays are reflected from the snow!
Medications – Tetracycline’s, sulfa drugs, birth control pills, diuretics and tranquilizers are examples of medications that increase your body’s sensitivity to UV and HEV radiation.
Cloud Cover – This has no significant effect on UV levels! UV radiation can penetrate clouds, and clouds can further scatter UV radiation to the Earth’s surface. UV exposure risk is still high and may actually be greater on hazy, overcast days!
Standing in the shade reduces your overhead UV and HEV exposure to some degree, but remember that UV rays are invisible and are being reflected off of buildings, roadways and other surfaces around you.
Here are examples of different surfaces and how much UVB radiation is reflected off of each:
• Fresh snow: 88%
• Dirty snow: 59%
• Sea foam (surf): 25-30%
• White house paint: 22%
• Dry sand: 15-18%
• Concrete pavement: 8-12%
• Wet sand: 7%
• Black asphalt: 4-9%
• Grass in winter: 3-5%
• Grass in summer: 2-4%
What To Look For In Sunglasses
• Look for sunglasses that block 100% of UV rays.
• Larger lenses provide greater protection to your eyes and the surrounding skin. In fact, 5-10% of all skin cancers occur in the eyelids, which is why this area requires protection as well.
• Wraparound styles also limit the radiation reaching your eyes from the periphery.
• If you wear contact lenses, invest in a pair of sunglasses that you can wear over your contact lenses. Also, ask your optometrist about which contact lens brands block UV radiation!
• If you wear glasses, ask your optometrist or optician about lens materials that inherently block 100% of UV radiation. In addition, prescription sunglasses ensure you’re comfortable in bright sunlight while also protecting your eyes from harmful, non-visible radiation.
• If the expense or inconvenience of a second pair of prescriptions sunglasses is an issue, look for fit-over or clip-on sunglasses. Both are 2-in-1 options designed to be worn over prescription frames.
• Depending on your lifestyle, sport or performance sunglasses may be a good option. For example, skiers and snowboarders should wear ski goggles with UV protection at all times while on the slopes.
• UV protection is not correlated to the color or darkness of the lenses, clear lens materials can block UV too!
Your optometrist and optician are happy to help you choose the best sunglasses for your needs!
Don't Forget The Kids!
After smearing your children with sunscreen, be sure to grab their UV blocking sunglasses before letting them out the door. Children tend to spend more time outside than most adults, increasing their UV exposure. The eye anatomy also makes them more susceptible to retinal damage from UVA rays. This is because the natural lens inside their eye is clearer than an adult lens, allowing more UV radiation to penetrate and reach the retina. Encourage your kids to wear quality sunglasses that block 100% of UV radiation, in addition to wearing a hat or visor while outdoors!
For more information about UV rays and the importance of sunglasses to your overall health, please contact us by calling 419-538-6273 or send us a website message.
Check out our latest special offers and opportunities to save on quality sunglasses by visiting this link: Special Offers
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