According to the Skin Cancer Foundation, just five or more sunburns over the course of a lifetime double your risk of melanoma, the most serious form of skin cancer. Here’s what you need to know.

Myth: I only need to wear sunscreen when I’m going to be outside and it’s sunny.

The Truth: Dr. Erin Lesesky, an assistant professor of dermatology at the Duke University School of Medicine, says she promotes the use of sunscreen every day: rain or shine, in the summer or winter. “That’s what I counsel every patient that comes to see me about … ‘What’s the biggest thing I can do to make my skin healthy and make my skin look better?’ ” she said.

Lesesky explains that we get a lot of sun exposure doing things like running errands, going to work or the grocery store, sitting outside at lunch, and even sitting by a window. Most of the sun’s rays can also penetrate clouds, so Dr. Elizabeth Rostan, director at Charlotte Skin and Laser clinic, says people should wear sunscreen even on cloudy days. And sun protection should be a daily habit rather than something you do for the beach.

Lesesky recommends using a sunscreen daily with an SPF of at least 30, and to apply it on exposed areas like the face and and forearms. She also says there are a lot of good daily moisturizers with SPF in them.

“So you don’t have to choose a sticky, gooey, smelly sunscreen as your everyday use,” Lesesky said.

Doctors say the proper amount of sunscreen is an ounce – enough to fill a shot glass.

Myth: A base tan protects against sunburn. The Truth: Tanning does little to shield you from sunburn. A suntan generated by ultraviolet light provides an SPF of just two to three for people with light to medium skin tones, according to the Skin Cancer Foundation. Base tans also don’t protect against sun damage, which happens at the cellular level, says Vilma Cokkinides, a cancer prevention epidemiologist with the American Cancer Society. Sun exposure causes changes in skin cells’ DNA, and these genetic mutations can turn into cancer over time, she explains.

Myth: I get tan but I don’t get sunburned, so I don’t need to use sun protection as much.

The Truth: “Just because you’re not getting sunburned, doesn’t mean you’re not getting sun damage,” Lesesky said. Tanning is “actually a very good sign, just as much as burning, that you’re getting DNA damage.”

Myth: I wear SPF 70, so I have nothing to worry about.

The Truth: The bump in protection offered by higher SPFs is minimal. For example, SPF 15 sunblock screens 93 percent of the sun’s UVB rays, while SPF 30 protects against 97 percent and SPF 50 against 98 percent, according to the Skin Cancer Foundation.

Myth: Water-resistant means waterproof. The Truth: Sunscreen isn’t waterproof. “Water-resistant means a dip in the water won’t wash it off right away,” says Cokkinides. Each time you take a plunge in the water – and towel off – the sunscreen loses its effect. Reapply after swimming or sweating.

Myth: I’m doing enough to protect my skin from the sun if I just wear sunscreen.

The Truth: “Really, sun protection requires … a compilation of different behaviors,” Rostan said. These include using a hat, trying to stay indoors during peak sun hours, finding shade when you’re outdoors and wearing sun-protective clothes, she said.

Myth: A hat protects my head and face.

The Truth: A hat is good for blocking the rays that come from directly overhead, but it doesn’t protect your face from the rays that bounce up from the ground. Many people don’t recognize they’re at risk for greater levels of damage when near water, sand and snow because of increased reflection, one doctor notes.

Myth: Light-colored clothing blocks sun best. You know better than to wear a black long-sleeved T-shirt on a run in the middle of summer. You opt for a lightweight white tee instead.

The Truth: Dark colors absorb heat and make you feel hotter, but they offer more protection from damaging rays than light colors do. Loose-fitting clothing in shades like deep blue and black and bright colors like orange and red offer more protection than white or pastel clothing, according to the Skin Cancer Foundation.

Myth: My race shields me from skin cancer. The darker your skin, the higher its concentration of melanin, a skin pigment that acts like sunscreen.

The Truth: Nobody’s immune. “Even if you don’t burn easily, you’re still receiving radiation,” says Cokkinides.

Myth: I need direct sunlight for vitamin D. In recent years, you’ve been bombarded about the benefits of vitamin D, from its ability to help you burn fat to its role in keeping bones strong. So you’ve set your sights on soaking up the sunshine vitamin.

The Truth: “Sun is neither a safe nor an efficient way to boost vitamin D,” says Dr. Maral Skelsey, director of the Dermatologic Surgery Center in Washington, D.C. “Most people who live in North America cannot get enough vitamin D with sun exposure alone.” She said it’s best to obtain vitamin D through diet and vitamin supplements.

Reporter Joanna Nolasco contributed