You may have heard lately that tattoos can potentially raise your risk of skin cancer. Recent research might complicate that narrative, however, suggesting that tattoos aren’t as harmful to our skin as assumed.
Scientists at the University of Utah led the study, published last month in the Journal of the National Cancer Institute. Contrary to their expectations, they found that people who had multiple tattoos actually had a lower associated risk of melanoma. That said, the findings don’t provide conclusive proof that tattoos can prevent skin cancer, the researchers caution.
“Further investigation is warranted to clarify these relationships,” they wrote.
An unexpected finding
Several recent studies have indicated that tattoos could pose a unique cancer risk. Just this March, for instance, a study of twins living in Denmark found that people with a tattoo had greater odds of being diagnosed with skin cancer (and lymphoma) than their non-inked siblings.
Tattoo ink can contain potential carcinogens, such as certain metals, and some researchers have speculated that the ink can agitate our body’s cells in harmful ways, causing inflammation or other changes that fuel cancer formation. By that logic, people with large or multiple tattoos should have a greater risk of skin cancer. And indeed, the Danish study did find that people with a larger tattoo had a higher risk than others.
With the help of cancer registry data, the researchers behind the new study attempted to survey as many Utah residents as possible who had been diagnosed with melanoma between January 2020 and June 2021, conducting the surveys by phone. All told, they obtained responses from 1,167 melanoma cases. They then compared these cases to controls matched in age, ethnicity, and other factors (this data was collected from a representative survey of Utah residents regularly conducted by the state health department).
As with the earlier Danish study, the researchers expected that the more tattoos someone had, the greater their odds of having skin cancer would be. But to their great surprise, they found otherwise.
People with two or more tattoos had a lower associated risk of both invasive and localized (also called in situ) melanoma, the results showed. The most apparent lower risk was seen in people who had four or more tattoos and in people with three or more large tattoos.
What to think about your tattoos
The researchers certainly aren’t ready to declare that tattoos will keep people safe from skin cancer just yet.
In their paper, they argue the lower observed risk in people with multiple tattoos is likely a sign of “unmeasured confounding”—meaning they might have failed to control for other important risk factors that could differ between people who get tattooed a lot compared to people who don’t. People who get multiple tattoos may be more vigilant about their skin care in general, for instance, and opt to wear sunscreen or stay out of the sun more often.
The researchers also point out that they still observed a small increased risk of skin cancer associated with only having one tattoo, further muddying the implications of their work.
“This isn’t a black and white case of ‘get more tattoos, and you could lower your risk of melanoma,’” said lead study author Rachel McCarty, a former doctoral student at the University of Utah’s Huntsman Cancer Institute, in a statement from the institute. “Instead, we need to do more research to understand what we are seeing and if this decreased risk is simply due to behavioral or physical factors, or if there could be beneficial immune responses associated with tattooing which lower melanoma risk.”
It’s worth noting at least one other recent study failed to find a link between potentially relevant cancers like lymphoma and tattooing. So at least for the time being, the jury is still out on whether people should be concerned about their tattoos and to what extent.
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