TikTok's No-Makeup Contour Hack Is Actually Super Unsafe, According to a Dermatologist

These days, TikTok is chock-full of fun beauty and skin-care hacks. And as summer heats up, there's a buzzy trend dubbed SPF contouring spreading on the app. It involves strategically applying more or less SPF (the level of sun protection a sunscreen provides) to specific areas of your face create a "naturally" contoured look without makeup. In other words, people are using tan lines instead of bronzer and highlighter to define their cheekbones and create a glowing effect on their nose and forehead. (Check it out: TikTok Found a Supergoop Face Sunscreen Dupe at Trader Joe's — Here's What a Dermatologist Thinks)

You might have seen some videos popping up on your For You Page showing a skin-care enthusiast or two applying a base layer of sunscreen all over their face followed by a layer of higher SPF only on the parts of their face they want to highlight (typically on the forehead, along the cheekbones, beneath the eyes, and down the center of the face). Worse yet, in some videos, users appear to skip the all over SPF step entirely, only applying sun protection to those areas they want to highlight. The goal here is to create a contoured look without bronzer or highlighter, but does targeted tanning really work and is it even safe?

Keep reading to find out why a dermatologist thinks this sunscreen trend is not only unnecessary, but potentially dangerous in the long run. (Psst: How Often Should You Really Get a Skin Cancer Screening?)

What is SPF contouring?

As mentioned above, SPF contouring involves a strategic placement of sunscreen (typically a lotion, rather than a spray) on the areas of the face where you'd usually put highlighter to mimic the way bronzer and highlighter work together to define prominent facial features for sharper-looking cheekbones and the appearance of a more defined nose bridge, for instance.

Some people start by applying a regular base layer of sunscreen to their entire face before adding extra to areas they want to highlight, while others seem to only apply sunscreen to desired highlight areas. It's supposed to create a "natural contoured look," as one creator calls it in a video clip, by allowing specific spots on the face to get more tan than others.

Does SPF contouring work?

SPF contouring may help some people achieve a contoured look without makeup, but only at the risk of the skin's health, Geeta Yadav, M.D., a board-certified dermatologist and the founder of FACET Dermatology, tells Shape. Essentially, you're offering more protection from the sun's UV (ultraviolet radiation) rays (which can cause sunburns and even skin cancer) to the parts of the face you've covered with sunscreen or higher SPF to highlight the skin.

This could provide a visible difference in skin tone between areas protected by more SPF than others after spending some time in the sun, but there's no guarantee the tan lines or burns will create the same glow and definition you get with bronzer and highlighter. Most importantly, improperly applying sunscreen could lead to more serious health issues, including sun damage and skin cancer, down line, says Dr. Yadav.

Is SPF contouring safe?

Over on TikTok, dermatologists and plastic surgeons alike are not convinced that this trend is safe, even if it does create a visibly contoured look, according to popular reaction videos shared on the app. "The truth is that most people don't apply enough sunscreen as it is — so making an intentional decision to improperly apply it is even worse," explains Dr. Yadav.

This has repercussions on both skin aesthetic and health. "We know that using enough sunscreen (and frequently reapplying!) slows the signs of aging, meaning that if you opt for inadequate sun protection, you'll see fine lines, wrinkles, skin laxity, and dark spots sooner rather than later," says Dr. Yadav. (Read more: SPF and Sun Protection Myths to Stop Believing, Stat)

"Beyond the cosmetic effects of not wearing sunscreen, you'll also be putting your health at risk," she adds. In addition to the potential for painful burns (as some TikTokers have experienced after trying the SPF contouring trend), using sunscreen incorrectly increases your chances of getting several types of skin cancer, says Dr. Yadav. "By simply applying SPF 30 or higher correctly on a daily basis, you can dramatically reduce your chances of contracting skin cancer," explains Dr. Yadav, adding that melanoma, a type of skin cancer, is one of the deadliest forms of cancer. That's why you don't want to mess around when it comes to proper sun protection.

You can use sunscreen to create a makeup-free contour look: true or false?

Just because you can use sunscreen to create a "natural" contour, doesn't mean you should, says Dr. Yadav, especially when there's no shortage of makeup products and easy contouring tutorials out there to help you get the same beauty effect without the risk of sun damage or skin cancer. "Trends that put you in danger aren't worth trying — just use makeup to contour instead," concludes Dr. Yadav.

And if a year-long summer glow is what you're after, you can always try the safe and easy "sunburn" blush trend, which involves using blush on the nose and cheeks to mimic the look of a sunburn without the painful and potentially dangerous sun exposure. (Next up: 3 Genius Ways to Reapply SPF Without Messing Up Your Makeup, According to TikTok)