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Sun Exposure Can Cause Long-Term Damage to Your Eyes
Interviewer: Find out how sun exposure can affect your sight and how best to protect yourself. We're with Dr. Jeff Pettey. He's an ophthalmologist from the University of Utah Health. What are some of the problems and risks that people face with sun exposure and their eyes?
Dr. Pettey: That's a really great question. All of us are at risk for sun damage to our eyes. The same effects on our skin from chronic exposure to the sun can occur in our eyes. That can result in things like cataracts, which could cause blurring of vision, that can also result in things such as growths on the surface of the eye or, in some cases, even increasing your risk of tumors or cancers on your eye.
High-Risk Environments Increase UV Damage to Your Eyes
Interviewer: So, what type of activities and exposure should people be on the lookout for with their eyes?
Dr. Pettey: Similar to the same type of concerns that you would have with skin. If you're out somewhere where you can get reflected ultraviolet rays at you, skiing, boating, really even out in our Utah deserts, you get a lot of reflection, that's going to increase the dose of ultraviolet light that's hitting your eyes.
Now, there are acute events that can occur, for instance, particularly in our climate, it's a sunny day, you'll get the intense UV light from being at altitude. Often as much as 90% of that ultraviolet light can be reflected. So you get these double doses, and that could result in one of the worst, most painful eye conditions we see, something called ultraviolet keratitis. It's been described aptly as taking sand, opening your eyes, and just pouring the sand directly in your eyes, and then closing your eyelids.
Everyday Sun Exposure Still Adds Up Over Time
Interviewer: So that's for people out in extreme exposure, people that are skiers, hikers, adventurers, what about just everyday people? People driving to work every day without their sunglasses, what kind of problems can they feel?
Dr. Pettey: The specific issues that we find are chronic conditions such as cataracts, and the specific growths that you can see on the eye. One is called a pterygium. The other is called a pinguecula. That's long-term scar tissue that can develop. Pterygium can actually start growing across the front of your eye. In many parts of the developing world, we'll actually find people who are blind from chronic sun exposure from pterygium.
Interviewer: So these aren't people who are like looking at the sun directly. These are just everyday long-term types of effects?
Dr. Pettey: Yeah, correct. That's the long-term effect. Now, one thing that is pertinent to something like an eclipse is when people view the sun directly, and if they do view the sun directly, whether that's on a regular day or whether that's during an eclipse, they're at risk of having something called solar maculopathy. That's basically where the sun's rays are all being focused on a part of your eye called the macula. The macula is responsible for all of your detailed vision.
So, looking at the sun for too long directly can result in you having a permanent smudge in the center of your vision as you try to read a line of print, you have that smudge follow you as you look at someone's face, and that smudge will be directly on their face. And in its worst form, that's permanent.
Sunglasses Are the Simplest Way to Protect Your Eyes
Interviewer: So, chronic high altitude, direct looks, and stuff like that, all sorts of problems that can happen with the eye. What are the best ways for people to protect themselves?
Dr. Pettey: So let's just start simple with sunglasses. Sunglasses will block out likely 100% of the UV light. If you look, your sunglasses, they should have a certification saying they block 100% of both UVA and UVB light. If you wear regular glasses, I'm not talking sunglasses, but just regular glasses, day to day, those lenses will also have UV protection built into the lens itself. And so that's just as good as wearing sunglasses when you're outside.
Interviewer: Really? So, just because they're darker doesn't necessarily mean they protect you from the sun more?
Dr. Pettey: That's correct. There's a layer in the glasses that's actually built into lenses nowadays that will block ultraviolet light and that will block ultraviolet light whether it's a clear glass that you need just for simple nearsightedness or farsightedness. That same layer will be in sunglasses. So, having a darker tint just overall allows less light into your eye.
The tips for the type of sunglasses you would want, bigger is better. The more coverage you can have of your eyes, the better. You do not need to get a dark tint. Tinting doesn't actually decrease the amount of ultraviolet light hitting the eye. That ultraviolet light will be blocked by the glasses themselves.
Finally, things like polarization again, polarization helps with optics, but it has no effect on ultraviolet blockage through the lens. So, as long as you have a pair of glasses that are relatively large to provide good coverage, that's the best recommendation. And wear those every time you're outside in the sun.
updated: July 15, 2025
originally published: September 27, 2017
