Melanin lenses in London. What is melanin and why is it so good at protecting us against the harmful effects of UV radiation?
Melanin is best known as a skin pigment. It gives us different skin complexions depending on the amount of melanin we have. The less melanin we have the paler the complexion and the more we have the darker the complexion.
However, melanin is also made by our bodies in response to UV light. This is known as the familiar tan so many of us crave.
Melanin is found in the eyes and helps protect against the damaging effects of UV radiation. It also helps reduce the effect of glare from stray light in the eyes. 90% of the light that enters the eyes is absorbed by the melanin, allowing us to have better vision.
With age the melanin levels in our eyes fall causing a greater risk to UV damage and also to glare. Some people may also have abnormally low levels of eye melanin that causes poor vision.
Melanin lenses as sunglasses give 100% UV protection and also filter 98% of blue light. They do a better job at UV protection than standard tinted lenses. Why is this? Standard tinted lenses do not protect against HEV which is on the blue end of the spectrum.
Different types of UV light
- UVA = wavelengths 320-400 nm. Slightly blocked by the Earth’s ozone layer.
- UVB = wavelengths 280-320 nm. Strongly blocked by the Earth’s ozone layer.
- UVC = wavelengths 100-280 nm. Very Strongly blocked by the Earth’s ozone layer.
- HEV (high energy visible) = 400-500nm. Not blocked by the Earth’s ozone layer.
Melanin lenses and macular degeneration
Macular degeneration is a degenerative condition that affects the aging population and is linked to among other things light damage from free-radicals which are no longer absorbed by naturally occurring antioxidants found in the eye. These antioxidants (Lutein and Zeaxanthin) fall in concentration as we age. Melanin acts as an antioxidant protecting the eyes from harmful free radicals.
Sunglasses with melanin tints give the best protection against free-radicals being produced by the UV and HEV spectrum.
Melanin lenses in London
TAVAT sunglasses are one of the few manufacturers of high quality melanin sunglasses and ophthalmic/prescription glasses with melanin clip-ons.
Oldfields Opticians in North West London stocks TAVAT ophthalmics and sunglasses with the option of clip-on or full sunglasses. Contact us for more information.