Getting a tattoo is a significant decision, and people often invest a lot of time researching design, placement, and style. However, the long-term health impact of tattoos is frequently overlooked.
Recent research has shown that tattoo ink particles can migrate to the lymph nodes, where they accumulate. Researchers from the University of Southern Denmark (SDU) and the University of Helsinki have investigated whether this accumulation could have health consequences. Using data from Danish twin pairs, they found that tattoo ink may increase the risk of skin and lymphoma cancers.
Tattooed individuals are more frequently diagnosed with skin and lymphoma cancers compared to those without tattoos. Scientists are concerned that tattoo ink may trigger chronic inflammation in the lymph nodes, which could lead to abnormal cell growth and an increased risk of cancer.
A clinical professor at SDU, Henrik Frederiksen explained, “We can see that ink particles accumulate in the lymph nodes, and we suspect that the body perceives them as foreign substances. This may mean that the immune system is constantly trying to respond to the ink, which could weaken the function of the lymph nodes or have other health consequences.”
Studying this link is challenging because cancer can take years to develop. This means that exposure in youth may not lead to illness until decades later, making it difficult to measure a direct effect.
The study used data from the Danish Twin Tattoo Cohort, which includes information from over 5,900 Danish twins. By analyzing tattoo patterns and cancer diagnoses, researchers found a higher occurrence of skin and lymphoma cancers in tattooed individuals.
Jacob von Bornemann Hjelmborg, a professor of biostatistics at SDU, highlighted that comparing twin pairs where one has cancer but shares many genetic and environmental factors provides a stronger method for investigating whether tattoos may influence cancer risk.
The study found that the link between tattoos and cancer is most evident in people with large tattoos (bigger than a palm). For lymphoma, the rate is nearly three times higher in individuals with large tattoos compared to those without tattoos. This rate accounts for age, the timing of the tattoo, and how long the individuals have been followed.
Signe Bedsted Clemmensen, assistant professor of biostatistics at SDU, suggests that larger tattoos and their more extended presence may cause more ink to accumulate in the lymph nodes. The impact on the immune system needs further investigation to understand the mechanisms at play.
Another Danish Twin Tattoo Cohort study shows that tattoos are becoming more common, with four in ten women and three in ten men expected to have tattoos by age 25. An independent Swedish study from 2024 also observed a link to lymphoma.
Previous research has suggested that some pigments in tattoo ink might be more problematic. “Our study did not find a clear link between cancer and specific ink colors, but this does not mean color is irrelevant. Other studies show that ink can contain harmful substances; for example, red ink often causes allergic reactions. This is an area we want to explore further,” says Signe Bedsted Clemmensen.
Journal Reference:
- Signe Bedsted Clemmensen, Jonas Mengal-From et al. Tattoo ink exposure is associated with lymphoma and skin cancers – a Danish study of twins. BMC Public Health. DOI: 10.1186/s12889-025-21413-3
