Not to throw shade at you, but if you're not wearing sunglasses, your eye health may be in a dark place.

That's because sunglasses protect your eyes — and eyelids — from the damage that ultraviolet (UV) sunlight can do to them.

In fact, basal cell and squamous cell carcinomas on the eyelids are not uncommon; they account for approximately 10% of all skin cancers. (Basal cell is 90% of those.) Symptoms include a growth on the lid that is red, brown, or black; non-healing skin irritations; chronic infection or swelling of the eyelid; and loss of eyelashes.

In the eye itself, overexposure to the sun's rays may cause surfer's eye — a cloudy, wedge-shaped bump on the cornea that can trigger discomfort and interfere with vision — as well as sunburned eyes (called photokeratitis), which is caused by the sun scorching the cornea and the inside of your eyelids, triggering blurry vision, swelling, and sore, watery eyes.

Sunglasses that protect your eyes are either polycarbonate or have a special coating applied that blocks the UV rays.

Look for sunglasses with 95%-100% UV protection or a "UV 400" sticker. Brown, green, and gray lenses are the most protective.

To check how protective your current sunglasses are, ask your eye doctor or local sunglass retailer if they have a photometer that can test their effectiveness.

And remember, sunglasses aren't just for the beach or sunny summer days. They protect your vision year-round.

For more information on eye health, check out the revised edition of "YOU: The Owner's Manual."