SPF Myth-Busting with a Dermatologist

Regular SPF use can prevent early signs of aging, harsh sun burns and in worst cases, skin cancer, making it one of the most important steps in a skincare routine. However, SPF is also one of the most misunderstood.

While we know sunscreen is an everyday necessity, we may not know which type to use (protection factor, we’re looking at you), when to apply SPF in a skincare routine, or how different types of UV rays are actually affecting our skin. And with so much confusion and many misconceptions, it’s easy to misuse this must-have layer of defense.

To set the record straight, we sat down with Dr. Melissa Kanchanapoomi Levin, board-certified dermatologist and founder of Entiere Dermatology. Here, she breaks down which myths you shouldn’t buy (literally) into, while sharing her expert knowledge on sun safety and SPF.

Myth #1: I have dark skin. I don't need sunscreen.  

“This is wrong. While it is more difficult to see a sunburn or see the damaging effects of UV rays on skin with higher melanin content, every type of skin type is at risk of skin cancer.”  

Myth #2: My sunscreen is waterproof. I don't need to reapply.  

“All sunscreen needs to be reapplied. Sunscreen only lasts for 40 mins to 2 hours. UVB penetrates water, especially in shallow water. Also, sunlight can reflect off the water, leading to increased UV exposure on the parts of your body that are not in the water.”  

Myth #3: I wear the highest SPF 50+ or even 100+. I don't need to reapply.  

“False! The number of the SPF is how much protection from UVB rays over a period of two hours.”  

Myth #4: There’s SPF in my makeup. That’s plenty of protection.

“Unfortunately, this is false! Only less than a quarter of people apply the recommended amount of sunscreen. You need a nickel-sized dollop to the face and 1 ounce (or a shot glass) to the body.”  

Knowing just when to apply is as important as how much you apply. Sunscreen should be used before makeup as the final, most important step in your skincare routine. Rub a Broad-Spectrum SPF (to protect against both UVA & UVB rays) into skin 30 minutes prior to sun exposure. Be sure to reapply every two hours spent under the sun, as well as after swimming or perspiring.

Myth #5: It's cloudy. I don't need sunscreen. 

“If you're going outdoors, whether it's sunny, cloudy, overcast, foggy, or raining, you need sunscreen. Clouds filter less than 25% of the UV rays and while you may not feel the heat of the sun, the skin still will absorb UVA and UVB rays.”  

Myth #6: I’m indoors. I don’t need sunscreen.

“You should still be wearing your sunscreen every day, even indoors. Indoor UV exposure still occurs since ultraviolet radiation penetrates through glass. The type of UV radiation that is able to penetrate through glass is UVA which is has a large role in pigmentary conditions such as melasma as well as responsible for accelerating photoaging of the skin with brown spots, wrinkles, and fine lines.”  

To reiterate, what is the most important thing you can do to keep skin healthy? 

“Safe sun behaviors are invaluable, and it is never too early to start. In fact, the sun is responsible for 90% of skin cancer. I am a firm believer of enjoying your life but to do so with healthy happy skin. Part of protecting your skin from the damaging rays of ultraviolet radiation (UV) is wearing daily sunscreen, which is why dermatologists always say, the best preventative or anti-aging skincare product is sunscreen. Using daily sunscreen is a must for skin care regardless of the time of the year.”