The short answer: A cataract is a clouding of the eye's natural lens, most often from aging, that makes vision blurry, dim, or hazy, like looking through a foggy window. It develops slowly and is very common after 60. Glasses can help in the early stages, but the only cure is a short, routine surgery that replaces the cloudy lens with a clear artificial one.

What a cataract is

Inside your eye, behind the pupil, sits a clear natural lens that focuses light onto the retina. Over time, proteins in that lens can clump and cloud it, and that cloudiness is a cataract. Because light no longer passes cleanly through, vision turns hazy and colors look faded. It usually affects both eyes, though not always equally.

Common signs

• Blurry, cloudy, or dim vision that glasses no longer fully sharpen.
• Colors looking faded or yellowed.
• Glare and halos around lights, especially at night and from headlights.
• Needing more light to read, and frequent prescription changes.

These can have other causes too, which is why an eye exam is how a cataract is confirmed.

What causes them

Aging is the main cause, but risk rises with lifetime UV exposure, smoking, diabetes, some medications, and eye injury. Protecting your eyes from UV across your life is one thing you can influence; see UV protection and your eyes. Most cataracts, though, are simply part of how the eye ages.

Can glasses help?

In the early stages, yes, up to a point. A stronger prescription, better lighting, and an anti-reflective coating to cut glare can keep you comfortable for a while. But glasses cannot clear a clouded lens, so as a cataract advances, new glasses help less and less. At that stage, surgery is the step that restores vision.

How cataracts are treated

Cataract surgery is one of the most common and successful procedures in medicine. A surgeon removes the cloudy lens and replaces it with a clear artificial one, usually in under an hour as an outpatient, with quick recovery for most people. It is done when the cataract interferes with daily life, not on a fixed schedule.

When to see an eye doctor

See an eye doctor if your vision is getting cloudy or dim, glare is worsening, or new glasses help less than before. Regular exams catch cataracts and other conditions early; see how often to get an eye exam. This article is general information, not medical advice; an eye doctor diagnoses and treats cataracts.

From our test bench. On the eyewear side, the useful takeaway is prevention and comfort: UV400 sunglasses across a lifetime are linked to lower cataract risk, and once early changes start, an anti-reflective coating noticeably eases the night glare people notice first. Neither replaces an exam, but both are worth doing.

FAQ

Can glasses fix cataracts?

Only early on. Stronger glasses and anti-reflective lenses help while a cataract is mild, but they cannot clear a clouded lens. Advanced cataracts are treated with a short surgery that replaces the lens.

What are the first signs of cataracts?

Blurry or dim vision, faded or yellowed colors, glare and halos around lights at night, and needing more light to read. An eye exam confirms whether a cataract is the cause.

Do sunglasses help prevent cataracts?

They can help. Lifetime UV exposure is a risk factor for cataracts, so wearing UV400 sunglasses over the years is a sensible protective habit, alongside not smoking and managing conditions like diabetes.

Part of The Complete Guide to Eye Health and UV Protection · Related: UV protection and your eyes · Browse eyeglasses · Last updated: August 5, 2026