You can't always believe what you hear. Which is why we took it upon ourselves to debunk some of summer's biggest beauty myths! And because so many of you still believe these urban legends, we HAD to lay down the facts. So, before you head back out there to soak up some sun, make sure you're doing it right.

Myth #1: SPF in makeup counts as sunscreen. C'mon, ladies, you should know better by now.Swiping on some foundation with SPF 15 in it just isn't going to properly protect you. According to New York-based dermatologist Dr. Bruce Katz in this article about wearing foundation under sunscreen, the level of sun protection in makeup is notoriously unreliable. To truly protect your skin from UV rays, you need to wear an SPF of 30 and look for these ingredients - zinc oxide, titanium dioxide and avobenzone. And applying once is not enough! Be sure to reapply every two hours - especially if you're out in the sun or going for a swim.

RELATED: Everything You Need to Know About Sunscreen

Myth #2: You need to use more powder to control sweat and oil.It's a common misbelief that you must use powder-based makeup (from foundation to blush, bronzer and even eye shadow) in the summer to keep skin looking matte and oil-free. But, humid weather and heavy powders aren't exactly a match made in heaven. Have you ever started sweating after applying powder and had those little dots of sweat pop up on top? Keep your skin glowing with a creamy, demi-matte foundation like L'Oréal Paris Infallible Pro-Matte Foundation and applying a bright cheek stain like YSL Kiss and Blush Summer Collection. You still get the benefit of oil-control, without the cakey feel that comes with applying layers and layers of powdered products.

Myth #3: Your hair doesn't need sun protection.According to Los Angeles-based stylist Anna Wiles, "sun protection for hair is especially important for you ladies with colored hair. It keeps your color from oxidizing or fading, plus not everyone wants the sun to lighten or lift their color!"

So, if you want your expensive color job to fade, then sure, you don't need it. But, if you want your hair to stay healthy, shiny and strong all summer long, give your locks a spritz of sun protection with a product like Matrix Biolage Protective Hair Oil or Kérastase Aqua-Seal - they work by sealing your strands with a waterproof veil to protect hair against UV rays and other water aggressors like chlorine and salt.

Click here if you want moremakeup, skin and hair advice for summer.

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