Look for UV protection details on product labels and the lens type when choosing sunglasses

​While most people apply sunscreen or carry an umbrella to protect the skin against harmful ultraviolet or UV rays of the sun, the potential dangers of long-term sun exposure to the eyes is often overlooked.

“UV rays have been associated with eye diseases such as the development of cataracts, age-related macular degeneration (AMD), pterygium, pingueculum and even skin cancers around the eyelids,” says Adjunct Assistant Professor Allan Fong, deputy head and consultant, General Cataract & Comprehensive Ophthalmology Department at the Singapore National Eye Centre.

In many cases, these eye conditions occur as a result of free radical damage due to exposure to UV rays.

According to Prof Fong, most of the sunlight that we are exposed to consists of two types of harmful rays: UVA rays and UVB rays. UVA rays can pass through the cornea, reach the lens, and retina inside the eye, playing a role in the development of cataracts and AMD, whereas UVB rays are shorter in wavelength and implicated more in surface eye problems such as pterygium. “These growths on the eye’s surface can become unsightly and cause corneal problems as well as distorted vision due to increase in induced astigmatism,” says Prof Fong.

Picking the right pair

To protect your eyes from harmful UV radiation, Prof Fong recommends getting a pair of sunglasses with a label that says 99 per cent to 100 per cent blocking or UV400 sunglasses.

Look for lenses that provide sun protection — fixed-tint sunglasses, adaptive lenses and polarised lenses.

Quality fixed-tint sunglasses are designed to absorb UVA and UVB rays and you should choose certain colours to suit the various activities that you plan to engage in.

“Amber-coloured or yellow tinted lenses help to improve contrast while driving, cycling or shooting. Brown, copper, dark amber tints are recommended for golfing, fishing, cycling, hunting, skiing and water sports,” says Prof Fong.

For those who are looking for convenience and flexibility under different lighting conditions, sunglasses that are made of adaptive lenses such as Transition lenses may be suitable for you. The special molecules in the lenses react to incoming light and block 100 per cent of UVA and UVB rays while reducing glare.

Polarised lenses are great for those who spend a lot of time driving, fishing and skiing. The polarisation blocks the light that reflects from the water or roads, thus reducing glare. “When we are exposed to glare, it can lead to eyestrain and fatigue. It may even be dangerous in certain activities,” says Prof Fong.

While most polarised lenses have built-in UV-blocking features, it is important to check the label to determine if they offer full protection. Do not choose a polarising lens with partial or no UV protection. Apart from the type of lenses, you should also opt for wrap around sunglasses or close-fitting sunglasses with wide lenses that protect your eyes from every angle.

Limit sun exposure

As the UV Index in Singapore by the Meteorological Service of Singapore often reaches very high and extreme levels between 11am and 3pm on a fair day, you should wear sunglasses even for that short walk to the nearest lunch place to protect against harmful UV rays. “It would still be wise to wear sunglasses even if there is no glaring sun as there is still the presence of UV rays. We should wear them whenever we are outdoors,” says Prof Fong.

He adds that it would also be advisable for children to wear sunglasses as their eyes are still developing, making them more vulnerable to UV damage.

“Studies have shown that increased exposure to UV rays in childhood can lead to higher risk of cataract and other problems in adult years. Some studies also reinforce that kids spend more time outdoors than adults, getting three times the annual sun exposure,” Prof Fong notes.

Hence, it is important for children to start protecting their eyes against UV damage early in life and continuing it through their adulthood.

He adds that wearing broad-trimmed caps and hats further enhances the protection from stray light coming around sunglass rims.