The sun, ultraviolet light, and your eyes

20 August 2026

When we think about the effects of the sun on our health, we usually think of the skin first. However, the eyes are also exposed to ultraviolet (UV) radiation on a daily basis, and over time, this exposure can contribute to the development of different eye problems.

UV radiation is part of sunlight and is present throughout the year, even on cloudy days. Therefore, protecting our eyes should not be an exclusive measure for days at the beach or on vacation, but rather a daily habit.

What is ultraviolet radiation?

Ultraviolet radiation is a form of energy emitted primarily by the sun. It is divided into different types, but UVA and UVB rays are the ones that are most relevant to our daily exposure.

Although the cornea and other structures of the eye can absorb a significant portion of this radiation, prolonged and cumulative exposure can cause damage to ocular tissues.

Additionally, the amount of UV radiation we are exposed to can increase in certain environments, especially near water, sand or snow, due to the reflection of sunlight.

How can the sun affect our eyes?

Excessive exposure to UV radiation can be related to different eye conditions.

Cataracts

Cataracts consist of the progressive opacification of the crystalline lens, the natural lens of the eye that allows images to focus.

Age is one of the main risk factors, but cumulative exposure to ultraviolet radiation can also contribute to the development of cataracts.

Pterygium

Pterygium is a growth of tissue on the surface of the eye that can progress toward the cornea. It is most commonly seen in people who spend a lot of time outdoors and are exposed to sun, wind, and dust.

In some cases it can cause redness, irritation, foreign body sensation or vision disturbances.

Photokeratitis

Intense exposure to UV radiation over a short period can cause inflammation of the cornea known as photokeratitis.

It may present with eye pain, tearing, redness, sensitivity to light, and blurred vision. It is similar to a sunburn, but on the surface of the eye.

This type of exposure can occur, for example, in environments where there is strong reflection of UV rays, such as the beach or snow.

How to protect your eyes from UV rays?

One of the simplest and most effective measures is to use sunglasses that offer adequate UV protection.
When choosing them, it is important to pay attention to the protection and not just the color or darkness of the lenses. A dark lens does not necessarily mean that it correctly blocks ultraviolet radiation.