Why Winter UV Protection Still Matters for Your Eyes

When the weather cools down, most Australians pack their sunglasses away. The thinking is reasonable on the surface: less glare, weaker sun, no need for shade. But winter UV protection is not about how warm or bright it feels outside. It is about how much ultraviolet radiation is reaching your eyes, and that does not drop to zero when summer ends.

Here is what the science actually says about UV in winter, and why a pair of sunglasses is worth keeping within reach all year.

UV radiation does not take a winter off

UV exposure is measured by the UV Index, a scale developed by the World Health Organization. In Australia, the UV Index regularly reaches 3 or higher through autumn and winter, particularly in the northern half of the country. A reading of 3 is the threshold at which sun protection is recommended for skin and eyes alike. In cities like Brisbane, Darwin, and Perth, winter UV levels can still climb into the moderate-to-high range on a clear day.

Two things explain why. First, the angle and clarity of the winter sun. Cooler temperatures often mean less humidity and clearer skies, and a low sun sits directly in your line of sight for longer periods of the day, particularly during morning and afternoon commutes. Second, reflected UV. Water, sand, concrete, and even light-coloured surfaces bounce UV back toward your eyes from below, adding to the total exposure that direct sunlight alone does not account for.

It is also worth understanding that UV is invisible. The brightness you perceive is a function of visible light, not UV intensity. A cool, overcast day can still deliver meaningful UV exposure to your eyes — clouds reduce visible light far more than they reduce UV radiation.

What UV exposure does to your eyes over time

Short-term, UV can cause photokeratitis — essentially sunburn of the cornea. It is uncomfortable, often described as a gritty or burning sensation, and usually settles within a day or two. Snow glare is the most common cause, which is why it is often called snow blindness, but it can happen from prolonged exposure to any high-UV environment.

The longer-term damage is what optometrists pay closer attention to. Cumulative UV exposure has been linked to:

• Cataracts — clouding of the eye's natural lens, and the leading cause of vision loss globally. The World Health Organization estimates that around 20% of cataract cases worldwide are linked to UV exposure.
• Macular degeneration — damage to the central part of the retina, affecting the detailed vision you use for reading, driving, and recognising faces.
• Pterygium — a growth on the surface of the eye, also known as surfer's eye. It is common in outdoor workers, beachgoers, and anyone with sustained sun exposure over years.
• Photokeratitis — the short-term version of UV damage, but recurring episodes can contribute to chronic eye health issues.

None of these conditions develop overnight. They build up over years of unprotected exposure, which is why year-round habits matter far more than any single day in the sun.

Who is most at risk

Everyone benefits from UV protection, but a few groups carry higher cumulative risk. Outdoor workers — tradies, landscapers, lifeguards, agricultural workers — accumulate UV exposure faster than office-based workers and should treat sunglasses as standard workwear, alongside a hat and sunscreen.

Children are another group worth flagging. The lens of a child's eye is more transparent than an adult's, meaning more UV reaches the retina. Childhood UV exposure is thought to contribute meaningfully to the risk of eye conditions later in life. Quality sunglasses for kids are not a vanity item.

And anyone with light-coloured eyes, a family history of cataracts or macular degeneration, or who has had eye surgery should be more conservative again. Speak to your optometrist if you fall into one of these groups.

What to look for in a pair of sunglasses

Not every pair of sunglasses provides genuine UV protection. The lens tint affects how bright the world looks, but it is the lens coating that blocks UV — and the two are not the same thing. A dark lens with no UV coating can actually be worse than no sunglasses at all, because the tint causes your pupils to dilate, letting more UV in.

Look for sunglasses that meet the Australian Standard AS/NZS 1067 and offer 100% UV protection (or UV400, which blocks all wavelengths up to 400 nanometres). The standard is the most reliable signal that the lenses do what they claim to do.

Polarised lenses versus UV protection

One of the most common points of confusion is the difference between polarised lenses and UV-protective lenses. They are not the same.

Polarisation is a filter that cuts horizontal glare — the kind you get bouncing off water, wet roads, or car bonnets. It improves visual comfort and contrast, particularly for driving and fishing, but polarisation alone does not block UV.

UV protection is a separate coating on the lens. A pair of sunglasses can be polarised, UV-protective, both, or neither. When buying sunglasses, check that UV protection is explicitly listed — and treat polarisation as a useful add-on rather than a substitute.

The takeaway

Winter is not a UV-free zone. Cumulative exposure does the long-term damage to your eyes, and the easiest way to manage it is to treat sunglasses as a year-round item rather than a summer accessory. Look for the Australian Standard, confirm UV protection is included, and wear them whenever the UV Index is 3 or above — which, across most of Australia, is most days of the year.

If you already have a prescription, prescription sunglasses are worth considering as a second pair alongside your everyday glasses. Every pair sold through Lenses Direct is reviewed by an Australian optometrist before it ships, with full UV protection as standard.