South Africa is one of the sunniest countries on earth. It is also one of the most UV-intense. And while most South Africans know to protect their skin from the sun, very few give the same thought to their eyes.

That is a problem — because ultraviolet radiation does not just burn skin. It silently and cumulatively damages the structures of the eye over a lifetime, contributing to some of the most common and serious eye conditions an ophthalmologist sees. Cataracts, macular degeneration, pterygium, and even cancers of the eye and eyelid are all linked to chronic UV exposure.

The good news: the damage is largely preventable. And protection is simpler than most people think.

Why South Africa’s UV Is Especially Dangerous

South Africa sits at a latitude that receives high levels of solar UV radiation year-round, not only in summer. Several factors make the risk here worse than in many other parts of the world. The country’s generally clear skies and low cloud cover mean UV reaches the ground at full intensity for more hours of the day. Higher-altitude regions — including large parts of Gauteng, the Free State, and KwaZulu-Natal’s midlands — receive stronger UV because there is less atmosphere to absorb the radiation. The proximity to the ozone-depleted regions over the southern hemisphere amplifies the issue further.

Many South Africans also spend significant time outdoors for work, sport, and daily commuting — often without any eye protection at all. The cumulative effect of this exposure, year after year, is where the real damage occurs.

How UV Radiation Damages the Eye

Cataracts

Chronic UV-B exposure is a well-established risk factor for cataracts — the clouding of the eye’s natural lens. UV energy accelerates the breakdown of proteins in the lens, causing them to clump and become opaque over time. Cataracts are the leading cause of avoidable blindness in South Africa and globally. Studies have consistently shown that people with higher cumulative sun exposure develop cataracts earlier than those who protect their eyes.

Macular Degeneration

The macula — the area of the retina responsible for sharp, central vision — is vulnerable to oxidative damage, and UV radiation is a contributor to that process. Age-related macular degeneration is the leading cause of severe vision loss in people over 50. While the relationship between UV and AMD is complex, reducing UV exposure to the retina is considered a sensible, evidence-supported protective measure — particularly in a high-UV environment like South Africa.

Pterygium

If you have ever seen someone with a fleshy, wing-shaped growth spreading across the white of the eye toward the cornea, you have likely seen a pterygium. This benign but unsightly growth is directly linked to chronic UV and wind exposure. In South Africa, pterygium is extremely common, particularly among people who work outdoors. If it grows large enough to encroach on the cornea, it can distort vision and may require surgical removal.

Photokeratitis — Sunburn of the Eye

Just as skin can sunburn, so can the cornea. Intense UV exposure over a short period can cause photokeratitis: a painful, temporary inflammation of the cornea. Symptoms include severe pain, tearing, light sensitivity, and a gritty feeling in the eyes. It usually resolves within 24 to 48 hours, but it is deeply unpleasant and entirely avoidable.

Eyelid Skin Cancer

The skin of the eyelids is among the thinnest on the body and is frequently overlooked when applying sunscreen. Basal cell carcinoma occurs on the eyelids more often than many people realise. Wearing sunglasses with large or wraparound frames provides meaningful protection to this vulnerable area.

How to Protect Your Eyes: Five Practical Steps

1. Wear Quality Sunglasses — Every Day. Look for lenses that block 99% to 100% of both UV-A and UV-B radiation. The label should say “UV400.” Lens darkness alone does not indicate UV protection. A dark lens without proper UV filtering is actually more dangerous than no sunglasses at all, because the dark tint causes the pupil to dilate, allowing more unfiltered UV to enter. Wraparound styles or large frames offer the best coverage.
2. Wear a Wide-Brimmed Hat. A hat with a brim of at least 7 to 10 centimetres can reduce UV reaching your eyes by up to 50%. Combined with sunglasses, it provides excellent protection.
3. Be Especially Careful Near Water, Sand, and at Altitude. Reflective surfaces dramatically increase UV exposure. Water reflects up to 25% of UV radiation. Sand reflects around 15%. At higher altitudes, UV intensity increases by approximately 10% for every 1,000 metres gained. If you are on Durban’s coast or hiking in the Drakensberg, your eyes are receiving significantly more UV than you might expect.
4. Don’t Forget Children. Children’s eyes are more vulnerable to UV than adults’. Their lenses are clearer, meaning more UV reaches the retina. The UV exposure accumulated in childhood contributes meaningfully to the lifetime risk of cataracts and macular degeneration decades later. Making sunglasses a normal part of a child’s outdoor routine is one of the simplest investments in their long-term eye health.
5. Know That UV Is Present Year-Round. In South Africa, UV levels remain significant throughout the year. On overcast days, up to 80% of UV still penetrates cloud cover. Protecting your eyes should not be seasonal. It should be habitual.

When to See an Ophthalmologist

If you are experiencing increasing glare sensitivity, a noticeable growth on the white of the eye, gradually blurring vision that new glasses do not resolve, or distortion of straight lines, it is worth having a comprehensive eye examination.

About Dr Johann Snyman

Dr Johann Snyman is a specialist ophthalmologist practising in Kloof and Westville, Durban. He treats the full range of UV-related eye conditions including cataracts, macular degeneration, pterygium, and ocular surface disease. As the founder of Africa20twenty — a non-profit providing free cataract surgery in rural South African communities — Dr Snyman sees first-hand the impact of preventable eye disease in populations with high UV exposure and limited access to care.