When it comes to eye health, there is no shortage of well-meaning advice passed between friends, family members, and colleagues. Some of it is sound. A surprising amount of it is not. And in a country where access to specialist eye care is limited for many people, myths can persist for generations — sometimes with real consequences.

Here are five of the most common eye health myths still widely believed in South Africa, and the clinical reality behind each one.

Myth 01 · Busted

“Reading in dim light ruins your eyesight.”

This may be the most universally believed eye myth in the world. The truth is that reading in low light does not cause permanent damage to your eyes or change your prescription. It can, however, cause temporary eye strain — symptoms like fatigue, headache, and difficulty focusing — because the eyes have to work harder to maintain focus in poor lighting.

Think of it like this: you can read a book using a torch in a dark room. It is uncomfortable and tiring, but it does not damage the paper, the torch, or your hands. The same principle applies to your eyes. Good lighting makes reading more comfortable and reduces fatigue, but dim light does not cause lasting harm.

Myth 02 · Busted

“Wearing glasses makes your eyes weaker over time.”

This myth persists in almost every community. Many people believe that once you start wearing glasses, your eyes become dependent on them and your natural vision deteriorates faster. This is not true.

Glasses correct a refractive error — they do not change the underlying structure of the eye. What often happens is that people get used to clear, corrected vision, and the contrast when they remove their glasses makes uncorrected vision feel worse than it did before. The progression of conditions like myopia or presbyopia is driven by natural processes — the growth of the eye in childhood and the stiffening of the lens with age — not by wearing corrective lenses.

In fact, in children, not wearing prescribed glasses can cause a far more serious problem: amblyopia, or lazy eye, where the brain fails to develop proper vision in the uncorrected eye. Glasses prescribed for a child should be worn as directed.

Myth 03 · Partly True

“Eating carrots will give you perfect vision.”

Carrots contain beta-carotene, which the body converts to vitamin A — a nutrient essential for healthy retinal function. A severe deficiency in vitamin A can cause night blindness and other serious eye problems. So there is a grain of truth here.

However, for anyone eating a reasonably balanced diet, additional carrots will not improve vision beyond its normal level. You cannot eat your way to 20/20 vision or reverse a condition like macular degeneration with carrots alone. The nutrients that have the strongest evidence for supporting eye health — particularly in age-related macular degeneration — are lutein, zeaxanthin, omega-3 fatty acids, zinc, and vitamins C and E. Dark leafy greens, oily fish, eggs, and nuts are more relevant than carrots for macular health.

Myth 04 · Dangerous

“If I can see fine, my eyes are healthy.”

This is arguably the most dangerous myth on this list. Good vision does not mean healthy eyes. The two most sight-threatening conditions an ophthalmologist diagnoses — glaucoma and diabetic retinopathy — both produce no symptoms in their early and moderate stages. By the time vision is noticeably affected, significant and often irreversible damage has already occurred.

Glaucoma silently destroys peripheral vision over years. Diabetic retinopathy damages retinal blood vessels long before central vision is affected. Both are detectable with a comprehensive eye examination — and both are far more treatable when caught early.

Myth 05 · Busted

“Cataract surgery is dangerous and should be delayed as long as possible.”

This myth causes real harm. Many patients endure years of progressively worsening vision — struggling to drive, read, and live independently — because they believe cataract surgery is risky and should only be done as a last resort.

The reality is that cataract surgery is one of the safest and most commonly performed surgical procedures in the world. It takes 15 to 30 minutes, is performed under local anaesthetic as day surgery, and most patients see a dramatic improvement within 24 to 48 hours. The complication rate is extremely low. Delaying surgery does not make it safer — in fact, a very advanced cataract can become harder to remove and increases the complexity of the procedure.

If cataracts are affecting your quality of life — your driving, your reading, your independence — the conversation about surgery should happen now, not in five years.

The Takeaway

Myths persist because they sound plausible and are repeated by people we trust. But when it comes to your eyes, accurate information from a qualified specialist is worth more than a lifetime of well-intentioned advice. If you have questions about your eye health, the most reliable answer comes from a comprehensive examination — not from a Google search or a conversation over the braai.

About Dr Johann Snyman

Dr Johann Snyman is a specialist ophthalmologist practising in Kloof and Westville, Durban. He welcomes questions from patients who want to separate fact from fiction when it comes to their eye health. His practice offers comprehensive eye examinations for adults and children, cataract surgery, glaucoma management, and diabetic eye screening.