The Effects of Sunlight on Eyes (and How to Protect Them)

Most people are aware that the sun can damage their eyes—or at least hurt them. The culprit is ultraviolet radiation, and its effects can damage eyes in the short-term and long-term, sometimes in unexpected ways.

UV Radiation in the Long-Term

Ultraviolet (UV) radiation exists in 3 forms: UVA, UVB, and UVC rays. The most damaging of the three is UVC, which is absorbed by the Earth's atmosphere. UVA rays cause damage to the retina (the light-sensitive membrane covering the back of the eye), although other parts of the eye absorb them as well. UVB rays are responsible for photokeratitis (a sort of sunburn of the cornea), cataracts, pterygium (a growth on the eye's surface), and a form of eye cancer called squamous cell carcinoma of the conjunctiva.

Damage in the Short-Term

While the aforementioned UV radiation can take years to show its effects, some damage can take effect almost immediately, such as photokeratitis and photoconjunctivitis (an inflammation similar to pink eye). The feeling of eye fatigue, soreness, and 'grittiness' after spending time on sand, snow, or water without eye protection is a result of UV radiation exposure.

Hidden Danger

Looking directly at the sun can damage the retina—hence the natural reaction to avert the eyes. UV damage can occur regardless of cloud cover or season of the year. In fact, fresh snow can reflect up to 80% of UV radiation. There is also no significant difference in time of day, although morning to mid-afternoon rays have been shown to be especially damaging.

How to Protect Eyes Against Damage

Sunglasses are often viewed as a fashion accessory, but their primary function is to protect eyes from harmful UV radiation. Eye protection is most beneficial when the lenses are gray and large enough to cover the eye completely. Wrap-around sunglasses are best. Some contact lenses provide a degree of UV protection, but most do not.

In addition to eye protection like sunglasses, ensuring proper sleep can help generate adequate lubrication to clear out irritants and repair daily damage. Call 603-430-5225 or contact your local eye care provider for further information.