Sun-Savvy: How to Choose the Best Sunglasses for Summer

Couple driving with sunglasses

Understand the benefits of wearing sunglasses, and how to choose the best option to protect your eyes.

No matter how you like to spend time outdoors in the summer, whether it’s participating in an active sport like hiking or biking, or just sitting by the water, having a good pair of sunglasses is important. Sunglasses help you see better in bright light, and they protect your eyes from many different dangers.  

In this article we’ll discuss the many benefits of wearing sunglasses and give you some tips for what to look for when purchasing a pair.

Why Wear Sunglasses?

Sunglasses are not only fashionable, they help protect you in several different ways:

  • Block ultraviolet rays. Exposure to the UV rays in sunlight can damage both surface tissues of the eye and its internal parts like the cornea and lens. UV rays can cause cataracts, eye cancer, and macular degeneration. Your eyes can even get sunburn, a painful condition called photokeratitis. Sunglasses with UV protection block harmful rays and help keep your eyes healthy.
  • Prevent skin cancer. UV rays can also cause skin cancer. Wearing sunglasses that block UV light protects the skin around your eyes and reduces the risk of developing skin cancer there.
  • Relieve eye strain. In bright sunlight, our eyes’ pupils get smaller to reduce the amount light entering the eye. When we go from a bright area to a darker one, the pupils open up to let more light in. Over time, this repeated adjustment can cause eye strain and fatigue. Wearing sunglasses reduces the need for your pupils to constrict, easing eye strain.
  • Reduce glare. Sunlight reflecting off water or surfaces like car windshields can produce glare, which makes it difficult for you to see and causes discomfort. Sunglasses can reduce glare, improving both safety and comfort.
  • Shield from debris. When you are outside there are many different types of debris floating about in the air, including dust, pollen, and insects. Sunglasses help keep foreign objects out of your eyes and protect them from irritation.

Tips for Buying Sunglasses

When you are shopping for a pair of sunglasses, here are some things to look for:

  • UV protection. Be sure to buy sunglasses that are labeled as having 100 percent protection from all UV light. Some labels may say UV absorption up to 400nm or UV400 protection, which is the same thing as 100 percent protection.
  • Light blockage. The amount of light that sunglasses let through to your eyes is called visible light transmission (VLT). The darker the sunglasses, the lower the VLT percentage. You’ll want to select a pair with a VLT of 40 percent or less. A 20 to 40 percent VLT is good for all-purpose use. A VLT of less than 20 percent would be best for bright, sunny conditions, but a very dark lens could make driving difficult as you encounter changing light conditions.
  • Lens quality. For nonprescription sunglasses, check that the lenses don’t distort your vision. You can do this by holding the glasses in front of you and looking at something with a rectangular pattern, like a tiled floor. As you slowly move the glasses, if the rectangular lines appear wavy or distorted, that’s a sign of poor lens quality and you should try a different pair.
  • Coverage. Look for sunglasses with larger-sized lenses that offer more coverage, thus providing greater protection for your eyes and the skin around them. Wraparound styles help reduce the UV light coming in from the sides.
  • Fit. Make sure that the sunglasses are comfortable and fit you well, so that you’ll keep them on during long days in the sun.
  • Impact resistance. The Food and Drug Administration sets minimum impact safety standards for sunglasses, so any pair should offer some protection. If you play sports or work outside, you may want to get a pair that has greater impact resistance, such as those with strong polycarbonate lenses.
  • Lens color. Sunglass lenses come in a variety of hues. Darker colors like gray and green won’t distort the colors you see and will help cut down on glare and eyestrain. Lighter colors like yellow and amber are used more for moderate to low light conditions and are meant to enhance contrast and depth perception.
  • Coatings. There are many different coatings available for sunglass lenses, such as scratch resistance and anti-reflection.

Polarization Pros and Cons

One of the biggest decisions you’ll have to make when purchasing a pair of sunglasses is whether to get polarized lenses.

Polarized lenses reduce the harsh glare bouncing off a smooth surface, such as water or glass. A special filter is applied to the lens which blocks horizontal light waves. This reduces the light you see reflecting off certain surfaces.

Polarized lenses can make some things easier to see, increase contrast, and reduce fatigue. They are popular with people who go fishing, boating, or to the beach. In the winter they are useful to reduce glare from snow when skiing or snowboarding.

However, polarized lenses have a big drawback. They can make it difficult to use a device with an LCD screen, like your phone. Many LCDs already have a polarizing filter to help you see them when outside, emitting only horizontal light. When you look at the screen with polarized sunglasses — which block horizontal light — the LCD will probably appear dark or completely black. You may also have trouble seeing LCD screens on gas pumps or ATMs if you wear polarized sunglasses. Heads up displays on vehicle windshields can be affected.

The solution when using your phone or tablet is simple — rotate the device so that the screen is visible while wearing polarized sunglasses. You can also take your polarized sunglasses off temporarily to see a screen better, such as when pumping gas.

However, those workarounds aren’t options for everyone. Vehicles like motorboats and airplanes often have LCD screens that can’t be rotated and it’s necessary to see those screens clearly to operate the equipment safely. Because of that, some people should not wear polarized sunglasses. For example, the Federal Aviation Administration does not recommend that pilots wear polarized sunglasses while flying.

What can you do? Having two sets of sunglasses (both polarized and non-polarized) would be ideal, so that you can choose the pair that best fits the situation. If that’s not an option, talk with your eyecare professional about what alternatives would work best for you.

Enjoy the Sun

Sunglasses are an essential piece of gear for enjoying summer activities. We hope the next time you’re outside in the sun, you’ll put on your favorite pair of shades to protect your eyes and keep them healthy.