Sunrays are bad for your skin. True. But do you know that it’s equally bad for your eyes? Harmful UVA and UVB rays can cause extensive damage to your vision. What can you do to protect your eyes? Simple – wear a sunglass. It is a great fashion accessory and surely there’s a cool-factor attached to it but when it comes to protecting your eyes the right sunglass goes a pretty long way.
How Ultraviolet Radiations harm your Eyes?
UV rays are invisible and are of three types:
1. UVA rays
UVA Rays are closer to visible light rays. Compared to UVB and UVC rays UVA rays have low energy. But these rays can pass through the cornea, reaching the lens and the retina in the back of your eye. Overexposure to this radiation can cause certain types of cataracts. Also, UVA rays may also cause macular degeneration.
2. UVB rays
UVB rays have a bit longer wavelength than UVC rays but are lower in energy than them. While the Ozone layer filters UVB rays buts still a certain percentage reach the earth. In low doses, this radiation stimulates the production of melanin, giving you a suntan. However, in higher doses, UVB rays can increase your risk of skin cancer. It also causes wrinkles, skin discolorations and other signs of premature skin ageing. This ray also causes pingueculae and pterygia. These are growths on the eye’s surface and may distort your vision. UVB rays may cause photokeratitis. This is a painful inflammation of the cornea. Severe photokeratitis (commonly called Snow Blindness) may cause temporary vision loss that may last from 24 to 48 hours.
3. UVC rays
This is the highest-energy UV rays and is the most harmful of all. Thankfully, the Ozone layer all UVC rays but depletion of the Ozone layer means UVC rays reaching the earth causing severe skin and eye issues and other UV rays related issues.
HEV Radiation Risks
High-Energy Visible or HEV rays or blue light, is visible. Although this ray is low in energy than UV rays, they penetrate your eyes deeply and cause severe damage to the retina. With low blood plasma levels of vitamin C and other antioxidants, HEV rays can cause macular degeneration.
If you love to spend most of the time of day outside, then you are at greater risk of damaging your eyes. The damage from UV and HEV rays depends on a few factors:
- Your Geographic location
Tropical areas (near the equator) have the greatest levels of UV rays.
- Altitude
The levels of UV rays are higher at high altitudes.
- Time of day
Levels of UV and HEV rays are high when the sun is high in the sky from 10 a.m. to 2 p.m.
- Setting
Levels of UV and HEV rays are high on open spaces especially on highly reflective surfaces such as the sand and snow. UV exposure is double when these rays are reflected from the snow.
- Medications
Certain medicines such as the sulfa drug, tetracycline, diuretics, birth control pills, and tranquillizers, can make your body sensitive to UV and HEV rays.
If you think that you are safe on a cloudy day, then you are wrong. Clouds never cover UV levels. In fact, your risk of UV exposure is very high on cloudy days. This is because UV is invisible and can penetrate clouds.
Source: http://www.allaboutvision.com/sunglasses/spf.htm
Does Sunglass Really Protect your Eyes?
Be it sunny days or cloudy, UV rays are always there. Moreover, certain elements such as grass, concrete, snow and water can reflect UV rays. This is equally harmful as direct UV exposure. And if your eyes are unprotected, then an excess amount of UV exposure even for a short period of time can cause Photokeratitis. This condition is also known as a “sunburn of the eye.” This condition is extremely painful. The symptoms include:
- red eyes
- a feeling of a foreign-body in the eye or a gritty feeling
- extreme sensitivity to light, and
- excessive tearing
The good news is these conditions are usually temporary and rarely causes permanent damage to the eyes.
Long term exposure to UV rays in the course of your life may result in many serious eyes conditions such as cataracts, age-related macular degeneration, pterygium (an abnormal growth in the cornea) and cancer of the eyes or eyelids and the skin around the eye. Sunglasses with UV ray protection can help you prevent these conditions. These glasses safeguard your eyes from the harmful UV rays.
Source: https://www.aoa.org/patients-and-public/caring-for-your-vision/uv-protection?sso=y
Not only it protects you from eye conditions but it also helps avoid wrinkles at the corners of your eyes. Too much sun exposure can cause wrinkles around your eyes (often called Crow’s feet). Moreover, it also protects the whites of your eyes.
Source: http://www.webmd.com/eye-health/features/how-to-pick-good-sunglasses#1
If you are considering wearing UV protected contact lenses then you may do that but these contacts cannot replace sunglasses. It’s because, with the contacts, the white part of the eyes are still exposed to damage from UV rays. That’s why wearing a sunglass is essential.
Types of Available Lenses
Have you ever thought about the type of lens while buying a sunglass? The answer is quite obvious- No. Most of the people judge a sunglass by its style aspects but when it comes to protecting your eyes, considering the lens type is also important. And an optician is the only one who can guide you while choosing the perfect sunglass. You will find sunglasses with a wide range of lenses on the market. Here’s a quick guide:
1. Blue-blocker
As the name suggests, this lens blocks blue light. Blue light is harmful to eyes and can increase the risk of eye damage by causing conditions such as macular degeneration. Blue-blocker lenses are extremely popular among pilots, skiers, boaters, and hunters. They use this type of lens to heighten contrast.
2. Polarized lenses and Lenses with anti-reflective coating
Both types of lenses reduce reflected glare. Polarized lenses are widely used by those who are into water sports or snow sports. On the other hand, Anti-reflecting coatings eliminate glare caused by light that’s reflecting off the back surface of the lens of your sunglass.
3. Mirror-coated lenses
This type of lens helps limit the amount of rays that’s entering your eye, making your much comfortable.
Mirror coatings are highly reflective and are applied to the top surface of your sunglass lenses. This helps in reducing the amount of light that enters your eyes. This type of lenses is extremely beneficial for people who indulge in activities in very bright conditions, such as during bright sunny days or during snow skiing on a sunny day.
The mirrored sunglasses are available in all colours including silver, gold, copper, and other metallic colours. You will also get mirrored sunglasses in colours such as hot pink, blue and any other colour that you could think of. While choosing the colour absolutely depends on your sense of style but do not think that the colour of coating has anything to do with your colour perception. The tint is determined by the colour of the lens below the coating. So, don’t expect to see the world turn pink wearing those hot pink mirrored glasses.
4. Gradient lenses
These lenses tinted from the top down, so the top of the lens is the darkest. Gradient lens is good for driving as it shields your eyes from overhead sunlight while allowing more light through the bottom half of the lens so that you may clearly see the dashboard.
5. Double gradient
This type of lens is also tinted but from the bottom up. So the top and the bottom of the sunglass are the darkest while the middle part has a lighter tint. This type of lens is a great choice if you want sunglasses that are not too dark, but protect the eyes from bright overhead sunlight and light reflecting off the water, sand or any other reflective surfaces.
6. Photochromic lenses
This type of lens adjusts their level of darkness on the basis of a number of UV rays they are exposed to.
Source: http://www.allaboutvision.com/faq/sunglasses.htm
How to choose the Right Shades?
Here is what to consider before buying sunglasses:
1. Does it block both UVA and UVB rays?
Before you check the price or brand, check whether the glasses block 100% of both UVA and UVB rays or not. If not, do not buy them. This is not too much to expect from a quality sunglass.
2. Does it fit right?
If it doesn’t fit well then it can let UV rays seep onto your eyes and skin. You may fall in love with the great style and amazing design of the sunglass and your heart may ache to leave it on the rack but do it if it doesn’t fit you. Think about your eyes. They are more precious than style! Look for something that sits well on your nose, doesn’t touch your eyelashes, doesn’t need to be pushed, and is in the line up with your brow. Sunglasses that wrap around your eyes are best for blocking stray UV rays and also protect your eyes from sneaky dust and sand particles.
3. Darkness and Color
Do not think that just because the lens is black, it blocks UV rays. Always check the label. The pupil (the black dot just at the centre of your eye) regulates how much light enters through it. So when you wear dark glasses, the pupil opens more to let in more light. And if the glasses are not UV protected, that means you more UV rays are entering your eyes.
4. Type of Lenses
Plastic or Shatterproof glass? Well, it’s completely your choice but check how much they help you to see clearly and protect your eyes. There are certain lenses that are too curved and a can distort vision. As long as the lens is UVA and UVB protected, you may buy any lenses.
Source: //www.webmd.com/eye-health/features/how-to-pick-good-sunglasses#1
5. Get Bigger glasses
This gives you more coverage and ensures that your eyes are safe from sun damage. Always buy oversized glasses or wraparound-style glasses. This will help cut down the levels of UV rays sneaking into the eye from the sides.
6. Price is not an indicator
High price doesn’t determine the quality of UV protection. Even costly sunglasses can be less effective in blocking harmful UV rays compared to less expensive glasses. As there is no uniform labelling of sunglasses, always consult the optometrist for selecting the best sunglass for your eyes.
7. Buy for your kid
Ensure that your child wears sunglasses when outdoors. Consider sunglasses with impact-resistant lenses and the frame has features such as spring hinges (if the kid is too active). Buy sunglasses with straps or ear pieces that wrap around the ear if the child is very young. If your child wears prescription eye glasses then make him/her wear prescription sunglasses.
A few Tips for protecting your eyes
1. Always wear sunglasses while going out. This is particularly essential during the peak sunlight hours. The sun rays are the strongest between 10 a.m. and 2 p.m. Also, wear sunglasses when you’re at higher altitudes. UV rays are pretty intense at high altitudes.
2. Wear sunglasses even if it’s cloudy. Just like you wear sunscreen even on a cloudy day, wear sunglasses even if it’s not sunny outside. UV rays can penetrate clouds and harm your eyes.
3. You may consider wearing a wide-brimmed hat. This also helps in blocking some UV rays from entering your eyes.
4. Sunglasses are not only for summers. Wear them throughout the year.
Source: http://www.everydayhealth.com/vision-center/lenses-and-beyond/investing-in-the-right-sunglasses.aspx
Hopefully, these tips will give you a fair idea about sunglasses and their characteristics. With the right pair of sunglasses, you can enjoy outdoor activities without harming your eyes. See your eye specialist frequently and get your eyes examined thoroughly. This is the best way for monitoring your eye health and maintaining good eye sight.