Is Tan-Through Swimwear Popular on TikTok? What Are the Risks of Sun Damage?

Tan-through swimsuits raise concerns about sun protection

Tan-through swimsuits are causing consumers to question proper sun protection protocol. A new type of swimwear is promising customers that it can prevent unwanted tan lines. The original “tan-through swimwear,” Kiniki, claims that these swimsuits contain microscopic holes that allow around 80% of the sun’s rays through, helping people achieve an even tan.

On TikTok, where “tan-through swimwear” has collected over 47 million views, tons of people who’ve put the suits to the test say the suits don’t leave harsh tan lines and boost exposure to Vitamin D.

The suits, per the fabric manufacturers, are not see-through. The tiny holes, complemented by busy prints, mean that the suits appear opaque from the outside eye. While they may help you avoid tan lines, tan-through swimsuits may increase your risk of sunburns, and in the long-term, skin damage.

“By allowing sun exposure to penetrate, mesh and see-through clothing leaves the area susceptible to sunburn and the potential for sun damage,” Marisa Garshick, MD, FAAD, a board-certified dermatologist at MDCS Dermatology: Medical Dermatology & Cosmetic Surgery Centers in New York, told Health.

While tan-through swimwear may provide some protection by covering the skin, they still let 80% of the sun’s rays through, meaning additional protection is a necessity.

Garshick cited a grading system called the Ultraviolet Protection Factor (UPF) that measures the percentage of UV rays that can penetrate fabric and reach your skin. Different types of clothing offer various levels of protection.

“For example, a white t-shirt provides little protection, with a UPF of about 7. When that t-shirt gets wet, the UPF protection is 3,” Garshick said.

A dark denim shirt, on the other hand, has a UPF of about 1,700. Some tan-through swimwear companies claim their suits contain low levels of SPF, ranging between 8 to 10 or 15 in most cases.

“Mesh or see-through clothing allows more UV rays to reach the skin, increasing sun exposure and the risk of skin damage,” Shoshana Marmon, MD, PhD, FAAD, an assistant professor of dermatology at New York Medical College, told Health.

It’s worth noting that dry clothing offers greater sun protection compared to wet clothing. So while tan-through swimwear may offer some protection, that protection will lessen if the swimsuit gets wet.

Garshick explained that many people only apply sunscreen to the parts of their body that are directly exposed to the sun, like their face, arms, legs, back, and stomach. But, with tan-through swimwear, people “may not realize that mesh and see-through clothing is enabling sun exposure in less-obvious areas” and forget to apply sunscreen there.

While a little extra time spent applying sunscreen may be inconvenient, prioritizing sun protection is a worthwhile endeavor.

Skin cancer is the most common type of cancer in the United States. Melanoma, while only making up 4% of skin cancer cases, is responsible for the majority of skin cancer deaths. A majority of melanoma cases stem from ultraviolet (UV) radiation exposure from the sun.

According to the American Cancer Society, unprotected exposure to the sun’s harmful ultraviolet rays dramatically increases one’s risk of skin cancer. In addition, UV rays can accelerate skin aging, lead to fine lines and wrinkles at a younger age, and cause sunburns.

Many people believe that only sunburns are harmful, Marmon said. “However, according to the American Association of Dermatology, a tan is a sign that your skin has been damaged by UV radiation.”

Tan lines are a clear indicator you’re getting too much sun. 

If you’re set on giving tan-through swimwear a try, Garshick recommends applying sunscreen to your entire body before getting dressed.

“Since mesh or tan-through pieces provide minimal protection against UV rays, it is important to treat areas under such swimwear just as you would fully exposed skin—with application and reapplication of sunscreen,” Marmon said. 

Try to reapply your full-body sunscreen every two hours or right after swimming or sweating. Ideally, aim for waterproof sunscreen that has an SPF of at least 30. Another tip: Search for products that are broad-spectrum because they offer protection from both UVA radiation, which ages the skin, and UVB radiation, which causes skin burns.

You can also check the weather forecast in your area to gauge how harmful the sun’s rays are. You’ll want to protect your skin if the UV index is 3 or more. 

The Skin Cancer Foundation recommends wearing clothing or swimsuits that have a UPF rating of at least 30. Clothing with a UPF rating of 50 blocks about 98% of the radiation emitted from the sun.

“It is best to look for swimwear that provides at least UPF 30 protection to provide extra coverage against the sun’s UV rays,” Garshick said. 

Ultimately, if you want to wear tan-though swimwear to get an even tan, bring along some sunscreen. And if you notice your skin is turning pink or golden, find some shade or throw on a cover-up. Not only will you keep your tan lines even, but you’ll help slow down the skin’s aging process and keep it looking healthy for years to come.