Dermatologist weighs in on the tan line trend

The viral social media trend of young people sunburning bikini tan lines into their chests continues to be seen across social media.

First seen in 2024, the trend has continued to grow, with the hashtag #tanlines reaching more than 1.2 million views on Instagram and major fashion labels continuing to use models with visible tan lines to showcase their clothing.

Royal Brisbane and Women’s Hospital (RBWH) Dermatology Clinical Lead Dr David Francis finds the trend concerning and wants people to know the risks.

“A tan line shows that your skin has reacted to the sun, and we know that sun exposure causes damage over time,” he said.

“Even if you don’t burn, having tan lines is showing you that you’ve had enough sun exposure, and if you continue to expose yourself to the sun you may be risking long term damage.

“I know there will always be people who like to follow trends, but in the case of this trend, there’s a chance it’s going to cause harm, particularly for people who are immunocompromised, have fair skin or have a close relative who’s had melanoma.”

While the importance of vitamin D in the human body is becoming more widely understood by the general population, David said there is some confusion around how much sun is needed for adequate absorption of the vitamin.

“Here in Queensland you only need about 10 minutes to the arms and legs, two to three times a week,” David said.

“It’s important for people to get this advice locally, as they may be hearing advice on how much sun in required for vitamin D from sources located in places with a much lower UV index.

“Queensland is the skin cancer capital of the world and has one of the highest UV indexes year round, therefore we need to be a lot more careful.”

David said that most people are aware of how to stay safe in the sun, but it’s important to continue to fine tune these practices.

“It’s great that we are seeing an increase in things like female swimwear with long-sleeves and beach shelter use,” he said.

“It’s important to remember to reapply sunscreen frequently, seek shade and wear a rashie.

“And if you really want to wear a specific bikini or boardshorts without a shirt, consider putting some sun safe clothes on as soon as you’ve finished swimming.”