The sun is out in force and it's time to select not only the trendiest, but also the most sensible pair of sunglasses that can filter out harmful UV rays. While darker lenses block out more light, they are not necessarily healthier for your eyes.
You can check whether the sunglasses are UV-protective by holding them up under a fluorescent light. A good pair breaks this into several discernible colors, while a cheap pair makes it appear uniformly white.
It is also advisable to avoid sunglasses that distort images or look darker in certain parts when they are moved up and down in front of the eyes, or those that reveal thin lines on the lenses akin to cracked glass when held up in the sunlight.
Shades in primary colors like red, green and violet are not recommended because they distort colors, which can cause eye strain. It also leads to potential confusion in discerning traffic-light and road-sign colors, increasing the risk of accidents.
During full exposure to the sun, such as on the beach, green- or grey-tinted sunglasses are considered the best choice. Yellowish lenses with a brown-tint are advisable for drivers because they do not interfere with color recognition, and yellow- or red-colored ones are best for taking in views from long distances, or on cloudy days, due to their clearer lenses.