As we age, protecting our eyesight becomes one of our most important priorities. And while we are told about the importance of wearing sunglasses throughout summer, could they be doing us more harm than good?

In some cases, yes.

Sydney ophthalmologist Dr David Robinson says that the wrong choice of sun protection for your eyes can mean you are actually increasing your risk of cancer.

He explains that many people confuse polarized lenses, which reduce glare, and glasses which offer UV protection. 

“Sunglasses which do not filter out UV light actually result in an elevated melanoma risk to the back of the eyes,” says Dr Robinson. 

“Some dark sunglasses, in particular, filter out the visible light meaning that our pupil size increases thus allowing more UV light into the back of the eye, which can increase people’s risk of melanoma at the back of the eye.”

While not advocating that we ditch our sunnies completely, Dr Robinson advises that we need to be prudent in our selection. 

“We need to buy sunglasses which 100 per cent satisfy the Australian standards,” he said. 

Since 1 July, 2019, all sunglasses sold in Australia must be tested and labelled according to the Australian/New Zealand Standard for Sunglasses and Fashion Spectacles (AS/NZS 1067:2016 Eye and face protection: Sunglasses and fashion spectacles).  This standard specifies the limits for the allowable light and ultraviolet radiation (UVR).

Unfortunately, the advent of online shopping in particular, means that many consumers are now purchasing and wearing sunglasses well below these standards, and this can have devastating effects on their health.

Apart from reducing the risk of melanoma to the back of the eyes, effective sunglasses also reduce the risk of many other eye health conditions.  Cataracts (a clouding of the lens of the eye) are generally thought to be caused by long term, unprotected exposure to UVR (with age, smoking, diabetes and family history also contributing factors).

Similarly, pterygium (a fleshy overgrowth of the conjunctiva or membrane on the surface of the eye) is also thought to be caused by too much exposure to UVR. 

Australia has one of the highest rates of pterygium in the world due to our lifestyle and climate. 

Dr Robinson advises consumers to consider sunglasses with appropriate side protection, such as wrap arounds. 

“Sunglasses which wrap around help prevent pterygium from occurring,” Dr Robinson explains. 

Dr Robinson also recommends people look for sunglasses with as large a lens as possible in order to prevent as much UVR from entering the sides of the glasses as they can.  This helps protect against basal cell carcinomas (BCCs). 

More than 50 per cent of BCCs of the eyelid initially occur on the lower lid of the eye, a place most people are unlikely to protect with sunscreen lotion. Large sunglasses that overlap the lower lid help prevent this condition.

Dr Robinson’s other top tip for choosing sunglasses is to consider the need for impact protection (with plastic lenses much less likely to shatter than glass).

“It’s also important to remember what our mothers told us when we were young: never look directly into the sun and don’t forget to slip, slop, slap,” he said.

Have you bought your sunglasses over the internet? Have you checked that they meet the Australian standard?