Experts say there are misconceptions about sunscreen and new research on effectiveness

With summer vacations around the corner and long days at the beach and ballpark ahead, it's important to know the best ways to stay protected against the sun. It starts with knowing how sun radiation works.

The sun actually has two types of ultraviolet rays; UVB rays, which make up 5% of the sun's radiation and cause burning; and UVA rays, which are more harmful and penetrate deeper into your skin.

UVA rays may not burn you, but they are the ones that mostly contribute to skin cancer, which is the most common type of cancer in the U.S., with more than 3.5 million people diagnosed each year.

So, even if you don't think you're burning, you could still be in danger. UV exposure for as little as 15 minutes can be damaging to your skin.

Sunscreen is a tried and true method of protection. It may seem obvious, but ABC13 found there are a number of misconceptions and new research on sunscreen effectiveness. Here are a few tips from our research and the experts we consulted:

Dr. Lisa Zhang, a dermatologist with Kelsey-Sebold in Houston, says to pay attention to the label.

• Look for sunscreen bottles labeled "Broad-spectrum SPF" that can protect you against both types of rays. Remember that SPF only measures the degree of protection, not how long the sunscreen will last.

• Apply sunscreen before you go out in the sun so your skin will have time to absorb the product.

• Don't trust any claims about water resistance.

"A lot of sunscreens will say they're waterproof but really none of them are. They will be water resistant for a period of time, but you still need to reapply sunscreen when you come out of the water," Zhang said.

• Keep in mind the need for sunscreen even if the sun isn't visible or if you're inside and near a window. Those harmful UVA rays can penetrate the cover of atmosphere and the glass of your car or airplane window.

• Use rash guards that can offer a significant layer of protection while still keeping you cool and water-friendly.

• Sunscreen pills act as an anti-oxidant inside your skin cells, but the FDA says they shouldn't be a replacement for actual sunscreen.

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"You cannot take the pill and think 'OK, I'm good.' You still need to apply your sunscreen as usual, every two hours. Wear your hat, sunglasses, your rash guard. The sunscreen pill may make it harder to get sunburnt, but it doesn't protect you 100%," Zhang said.

If you spot any sort of suspicious mark on your skin or just want to know more, consult your physician, but use the tools at your disposal to have safe fun in the summer sun.

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Less than 15% of men and 30% of women use sunscreen regularly on their exposed skin when outside for more than an hour, says the Centers for Disease Control and Prevention.

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