The research took into account factors such as skin type or sun exposure habits and nevertheless noted an increase in the risk of developing melanoma.
Can tattoos protect the skin from the sun’s harmful rays or do they make the situation worse? A new one published in suggests there may be reasons for concern. We found that people with tattoos had a 29% higher risk of developing melanoma, a serious form of skin cancer often associated with exposure to ultraviolet (UV) rays.
However, tattoos did not appear to increase the risk of squamous cell carcinoma, another type of skin cancer linked to damage caused by UV rays. Although both types of cancer share a common cause, they have originate in different cell types and differ in severity, with melanoma being much more dangerous.
Tattoos are a powerful form of self-expression and a pillar of modern identity. In Sweden, around one in three adults has tattoos, demonstrating how body art has become a common practice. Despite its popularity, scientists still don’t know if tattoos have any impact on health or how its potential effects may develop over time.
Epidemiologists are now trying to answer these questions. The work is challenging because people who choose to get tattoos often differ from those who don’t get them in aspects that can influence health outcomes.
Another difficulty is that most health records do not indicate whether a person has tattoos, which means that long-term patterns are difficult to study. Without this basic information, it’s difficult to know whether tattoos themselves play a role in health or whether the differences are driven by other factors.
Melanoma and squamous cell carcinoma develop slowly and are relatively uncommon, making long-term investigation challenging. Tracking large groups of tattooed and non-tattooed people over many years would be expensive and time-consuming. So the team took a different approach and started with people who had already been diagnosed with cancer and we looked back to see who had tattoos. This type of research, known as a case-control study, is an efficient way of detecting possible associations.
Sweden maintains high-quality national registers that store health and demographic information. From the National Cancer Registry, they identified all people aged between 20 and 60 who were diagnosed with melanoma in 2017 or squamous cell carcinoma between 2014 and 2017.
This included 2880 cases of melanoma and 2821 cases of squamous cell carcinoma. For each case, there were three comparison people selected of the same age and sex as in the Total Population Register, who had not been diagnosed with skin cancer.
Questionnaires were then sent to all participants, asking about tattoos, including decorative tattoos, permanent makeup and tattoos for medicinal purposes, as well as their size, location and age of first tattoo. This made it possible to determine whether the person had gotten the tattoo before or after developing cancer.
A total of 5695 people participated in the melanoma study (1598 with melanoma) and 6151 in the squamous cell carcinoma study (1600 with this type of cancer).
People with tattoos presented a 29% higher risk of developing melanoma compared to those who did not have tattoos. The increased risk appeared to be greater in people who had tattoos for more than ten years, although the number of cases in this group was lower, so the results should be interpreted with caution.
For squamous cell carcinoma, the tattoos didn’t make any difference. The results were consistent across all analyses, suggesting that there is no link between tattoos and this type of skin cancer.
There was also no evidence found that larger tattoos increase the risk. This was unexpected, given that the Bigger tattoos contain more ink and therefore more potentially harmful substances.
One possible explanation is that tattoo ink does not remain confined to the skin. The body’s immune system Treats it like a foreign substance and transports some ink particles to the lymph nodes. These particles can remain there for a long time. While we don’t yet know whether this causes harm, it could potentially lead to chronic inflammation, which has been linked to the development of cancer.
Another explanation could be measurement error: people tend to overestimate the size of the tattoo. Future studies with more precise measurements may help to clarify this issue.
Lifestyle and confounding factors
What makes this study unique is the variety of lifestyle factors that were considered. were included data on sun exposure (both occupational and recreational), use of solariums, smoking, education level, marital status and family income. We also take into account skin type, pigmentation, age and gender.
These details are important because they can influence both those who get tattoos and those who develop cancer. For example, people who spend a lot of time in the sun may be more likely to get tattoos and develop melanoma. Take these differences into account reduces bias and increases confidence in the results.
In research, this problem is known as confusion. If confounding factors are not properly controlled, they can distort results and lead to misleading conclusions.
Recent research in the US has suggested that large tattoos may even reduce the risk of melanoma, but this study did not control important factors such as skin type or exposure to UV rays. The results may therefore reflect behavior rather than biology. For example, people with large tattoos may avoid sunbathing or tanning beds to protect their body art, which would naturally reduce damage caused by UV rays.
So, do tattoos cause skin cancer? The simple answer is that we still don’t know. The results suggest a possible link between tattoos and melanoma, but a single study is never enough to prove causality.
More research is needed to explore possible biological mechanisms, such as chronic inflammation, and to examine how different types of paint or colors may interact with UV exposure. The composition of tattoo pigments varies greatly and many contain compounds that can break down into harmful byproducts when exposed to sunlight or laser removal treatments.
If you have tattoos, no need to panicbut awareness is important. Continue to protect your skin from UV radiation as you normally would: use sunscreen, avoid excessive tanning and check your skin regularly for new signs or changes to existing ones.
The results highlight the need for long-term monitoring and better data collection on tattoos in health records. With tattoos becoming common across the world, this is an important public health issue. Continued research into the biology of tattoos and their long-term effects will help ensure that people can make informed choices about their body, their art and their health.
