You probably wouldn't think of hitting the beach or enjoying a sunny day's excursion without your trusty sunglasses, not least because they make you look cool. But did you know that sunglasses provide some very real health and safety benefits, even on days when the sun is less than dazzling? Let's look at some important ways that sunglasses help you stay well.

1. Sunglasses Can Spare You From Photokeratitis

Ask any skier what snow blindness feels like, and the answer will probably make you reach for your sunglasses the next time you go out. White ski slopes and glittering beaches can actually give your eyes a kind of sunburn known as photokeratitis. Symptoms typically include eye redness, pain, watering, and a gritty "foreign body" sensation. You may even experience visual abnormalities. Thankfully, photokeratitis is temporary—but the UV (ultraviolet) exposure that causes it can add up to more serious problems over time. Sunglasses block this radiation even as they reduce the glare bouncing up from those bright surfaces.

2. Sunglasses Can Help Protect Against Permanent Vision Loss

UV rays don't just burn the front surfaces of the eyes; they can also do permanent damage in the form of serious eye diseases. Cataracts are one of the most common outcomes of long-term UV exposure. These milky formations in the lenses of the eyes can make your vision progressively blurrier until you can't see at all. Another eye disease associated with UV exposure is macular degeneration. This retinal disease slowly destroys your central vision, leaving only your peripheral vision intact, unless it receives prompt treatment. Even an overcast day can hit your eyes with enough UV to cause problems, so don't hesitate to wear your sunglasses, whether the sun is shining or not.

3. Sunglasses Can Lower Your Cancer Risk

You probably already know that UV rays can cause skin cancer, but have you considered that your eyelids are made of skin? People don't commonly apply sunscreen to their eyelids, meaning that the eyelids remain vulnerable to ultraviolet radiation. The ultimate result may be skin cancer, including the potentially deadly melanoma. Even the eyes themselves can develop cancerous tumors, with melanoma growing in the iris or the middle layer of the eye's interior. Wearing sunglasses that filter out UV wavelengths can save you from this nightmarish situation.

4. Sunglasses Block Blinding Glare

Sunglasses certainly make a bright day more comfortable, but even more importantly, they make that day safer to navigate. Reflections from cars, water, or other shiny objects can take on a blinding intensity under full sunlight. Just one such flash or glimmer at the wrong time could put you at risk for an auto accident or another hazardous event. You'll thank yourself for remembering your sunglasses the next time you're driving, boating, or walking in a bright, busy environment.

It's worth noting that not all sunglasses block UV or glare equally well. Ask your optometrist for UV 400 sunglasses, so named because they block the entire range of UV radiation. You might also want to ask for polarized sunglasses, which provide extra glare protection against light reflected from below. Buy (and wear) the right kind of sunglasses, and you can rest assured that you're doing your health a huge favor!