Eye diseases caused by UV radiation can be divided into 2 groups:
- Short-term diseases If the eyes are exposed to high-intensity or prolonged UV radiation, it can cause corneal inflammation (photokeratitis) with symptoms such as eye burning, tearing, light sensitivity (photophobia), red eyes, eye pain, and a feeling of having a foreign object in the eye.
- Long-term diseases UV radiation affects both the skin around the eyes and the eyes themselves, such as sunburned skin around the eyes, skin cancer, melanoma, pterygium, pinguecula, and cataracts.
One thing that can help protect your eyes and the skin around your eyes is sunglasses because they reduce exposure to UV radiation, similar to how sunscreen protects the face and body skin.
What should you look for when choosing good sunglasses?
There are 6 recommendations for choosing good sunglasses:
1. UV protection
You can easily check if the sunglasses you want to buy can protect against UV by looking inside the temple arm, where the CE mark, a European standard certification, should appear.
Observations
- The letters C and E must be 5 millimeters tall.
- There should be a specific spacing between the letters.
- The letters should be curved like a circle, and the inner curve of the letter C must match the outer curve of the letter E.
The UV400 or UV40 symbol indicates the filtering rate of the sunglasses that can protect the eyes. UV400 is the mark showing the best UV filtering performance, meaning it can block 100% of both UVA and UVB rays.
2. Glare reduction
Good sunglasses should be able to reduce glare or be polarized lenses. Since lenses are made from various materials such as glass or plastic, reflections can be seen when worn. Anti-glare lenses help make images clearer, improve visibility, and provide more comfort when worn.
3. Choose lenses suitable for activities
There are 3 popular types of lenses used for sunglasses:
- CR39 lenses are the most widely used plastic lenses because they resist scratches well and protect against both UV and infrared rays.
- Glass lenses are clearer and more scratch-resistant than plastic lenses but are heavier and can break in severe accidents.
- Polycarbonate plastic lenses are the lightest and impact-resistant, often used in sports or extreme activity glasses, providing the best eye protection.
4. What are the properties of different sunglass lens colors?
- Black is most suitable for outdoor activities.
- Gray helps filter light and reduce glare without distorting colors, ideal for beach trips.
- Orange or yellow enhances depth perception but distorts colors, making them unsuitable for driving.
- Brown improves color and natural light clarity, enhancing vision, especially for driving cars or motorcycles.
- Green filters and reduces glare well like gray, providing comfort and suitable for outdoor activities.
- Tea and dark gray are suitable for general use.
5. Choose frames that suit your face shape
Each person’s face shape is different. Here are recommendations for choosing suitable frames:
- Square face should wear round curved frames.
- Round face should wear large frames to cover the cheekbones, which makes the face look younger and emphasizes rectangular frames.
- Long face should wear oval frames that fully cover the eye area.
- Oval face can wear any frame style but looks best with rectangular light-colored frames.
As for frame size, choose large frames with wide temple arms to better protect the skin around the eyes. Good sunglasses should block light from all sides.
6. Try on sunglasses before deciding to buy
It is recommended to try on the sunglasses, walk around, look up and down to ensure they do not slip, and check that the lenses fit snugly in the frame without any bent temple arms.
“The effectiveness of sunglasses in blocking UV light generally lasts about 2 years.”
This depends on usage frequency; frequent use may cause faster deterioration. It is true that even minor scratches can allow UV light to pass through the sunglasses to the eyes. Therefore, taking care to avoid scratches and storing sunglasses in a proper case helps maintain their effectiveness.
For tinted lenses, fading color is another indicator that it is time to look for new sunglasses.
Even with good and standard sunglasses, it is important to always wear them when going outside, whether it is cloudy, overcast, or sunny, especially between 10:00 AM and 4:00 PM when UV radiation is strongest. Wearing sunglasses is also important for children.
However, wearing sunglasses alone may not be enough. Avoid places with high UV intensity, such as prolonged outdoor exposure. If unavoidable, wear a wide-brimmed hat or use an umbrella. Most importantly, remember to replace sunglasses every 2 years.
Dr. Natamon Srisamran
Glaucoma Specialist
Eye Center, Phyathai 1 Hospital
