UV Rays: an Ophthalmic Explanation

Revised and Updated by Seth Preston on: September 26, 2019

To learn a bit more about UV Rays, head over to our 7 Quick Summer Eye Safety Tips article!

The sun’s proven harm to the human body, especially the eye, has increased awareness of prolonged exposure to UV rays. How do the ultraviolet rays of the sun affect your eyes? Let’s dive in and get to the Ophthalmic explanation of how the sun can harm your eyes without proper UV protection.

Ultraviolet rays have a high energy, and are proven to be harmful to the body with overexposure. UV rays also have subsidiaries of severity when it comes to what is going into the eye.

  • UVC Rays: The highest energy rays. UVC rays are the main factor of skin and eye health because they are directly affected by the breakdown of the earth’s Ozone layer.
  • UVB Rays: These rays have the longest wavelength but not as much energy as UVC rays.
  • UVA Rays: The lowest energy rays. These have even larger, less concentrated wavelengths.

The higher the energy, the higher risk you run to direct exposure.

How do we gauge the danger to our eyes? Pictured below is the UV index implemented by the Environmental Protection Agency (EPA). As the index increases, the need for sunblock and protective clothing also increases.

Infographic on dangers of UV rays

Going outside without proper protection for your eyes is an ill-advised decision, and here’s why.

What can prolonged exposure to Ultraviolet rays do to your eyes?

  • Cataracts: UV light, especially UVB rays, increases your risk for certain types of cataracts. It is estimated that 10% of all cataract cases are directly attributable to UV exposure.
  • Macular Degeneration: Macular Degeneration (AMD) is caused by damage to the retina over time and is the leading cause of age-related blindness. Extended exposure to UV light increases your risk of developing macular degeneration.
  • Skin Cancer: Skin cancer in and around the eyelids is also linked to prolonged UV exposure.
  • Pterygium: Often called “surfer’s eye,” pterygium is a pink, non-cancerous growth that forms on the layer of conjunctiva over the white of your eye.
  • Photokeratitis: Also known as corneal sunburn or “snow blindness,” photokeratitis is the result of high short-term exposure to UV-B rays. Long hours at the beach or skiing without proper eye protection can cause this problem. It can be very painful and may cause temporary vision loss.

The eye is small, intricate, and above all, delicate. Necessary precautions must be taken to ensure healthy eyes!