How does sunlight damage to eyes occur?

It’s that time of the year again to soak up the delightful sun and enjoy the freshness of the outdoors. But let’s not forget that the sun can harm our eyes and skin if we’re not properly protected. We’re exploring just how sunlight can damage your eyes and how you can protect them with our help.

Why is UV protection important?

UV protection important

Although invisible to the human eye, the sun emits three types of rays: UVA, UVB, and UVC. Fortunately, UVC rays don’t reach us because they’re absorbed by the earth’s protective ozone layer. However, UVA and UVB rays do penetrate the atmosphere and can affect our eyes.

UVA rays can penetrate deep into the eye and can potentially damage the retina. On the other hand, UVB rays primarily affect the cornea and lens, leading to various eye conditions. It’s crucial to note that UV rays are present all the time, even on cloudy days, though the UV index varies throughout the year.

What eye conditions are linked to UV exposure?


This condition, characterized by the clouding of the eye’s lens, can take years to develop but can be accelerated by UV exposure. Cataracts can lead to blurred, cloudy vision and, if left untreated, can cause blindness.

Age-related macular degeneration (AMD)

AMD impacts the macula; the part of the retina which is responsible for sharp, central vision and is a leading cause of vision loss in older adults. UV exposure can damage the macula, increasing the risk of developing AMD.

Pterygium (surfer’s eye)

This condition involves a growth on the conjunctiva that can extend onto the cornea leading to blurred or blocked vision. Due to long-term UV exposure being the main cause, it is more common in people who spend a lot of time outdoors.


This is a yellowish, benign growth on the conjunctiva, often found in the corner of the eye. Luckily it usually doesn’t grow large enough to impact your vision. Like pterygium, it’s linked to prolonged UV exposure.


Essentially a sunburn of the eye, photokeratitis is a painful condition caused by intense UV exposure. Symptoms include redness, pain, and temporary vision loss.

Tips to prevent damage to eyes from the sun

Fortunately, there are many things you can do to protect your eyes. Here are our top 6 tips.

  1. Wear a wide-brimmed hat – This provides extra protection by shading your eyes from direct sunlight.
  2. Wear sunglasses that offer 100% UV protection – Look for sunglasses labeled UV400 to ensure they block all UVA and UVB rays.
  3. Avoid looking directly at the sun – This can cause severe eye damage, with or without sunglasses.
  4. Protect your children’s eyes – Since 80% of UV damage occurs before the age of 18, ensure children wear sunglasses and hats from a young age.
  5. Be mindful of peak sunlight times – UV rays are strongest from midday to early afternoon, at higher altitudes, and when reflected off water, so try to avoid these conditions.
  6. Check your prescription lenses – most now feature a UV filter. Confirm with your optometrist that your glasses include this essential protection.

prevent damage to eyes

Get in touch

For more advice on safeguarding your eyes from UV damage, get in touch or visit us at our optometrists in Ontario.