UV and Your Eyes: Why Sunglasses Need to Block 100% (Not Just Look Dark)
You protect your skin from UV - but the part most people forget is sitting right behind those sunglasses.
UV exposure contributes to cataracts and can cause photokeratitis, a painful corneal 'sunburn' common as snow blindness; the American Academy of Ophthalmology advises sunglasses that block 99 to 100% of UVA and UVB.
The American Academy of Ophthalmology advises choosing sunglasses that block 99 to 100% of both UVA and UVB rays, emphasizing that lens darkness is not the same as UV protection.
Questions we get a lot
How much UV protection should sunglasses have?
The American Academy of Ophthalmology advises sunglasses that block 99 to 100% of both UVA and UVB rays. Lens darkness alone does not indicate UV protection, so look for that rating rather than just a deep tint. Wraparound styles help block UV entering from the sides.
What is photokeratitis?
Photokeratitis is essentially a sunburn of the cornea caused by intense UV exposure, and it is commonly known as snow blindness when it occurs on bright, reflective surfaces like snow or water. It can be painful but is usually temporary. The AAO highlights it among UV-related eye harms.
Can the sun really cause cataracts?
Yes. UV exposure is a recognized contributor to cataracts, a clouding of the eye's lens that can impair vision over time. The American Academy of Ophthalmology lists UV among modifiable risk factors, which is why long-term eye protection matters as much as protecting your skin.
r/optometry: 'My cheap dark sunglasses don't list UV protection - is wearing them actually worse than nothing?'