Tattoos: Are They Toxic?

Summary

Science Vs — Tattoos: Are They Toxic?

Host: Rose Rimler (filling in for Wendy Zuckerman)
Released: May 7, 2026
Main Theme:
This episode investigates the health risks — particularly toxicity and cancer risk — associated with tattoos. With tattoos surging in popularity, the internet is awash with alarming claims about the dangers of ink. Science Vs meticulously slices through the hype, rumor, and fearmongering to focus on what the latest scientific studies actually say about tattoo ink, the behavior of ink in the body, potential cancer risks, immune reactions, and psychological benefits.

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Key Discussion Points and Insights

The “Toxic Tattoo” Debate (00:00-03:39)

• Host Rose Rimler outlines the episode’s big questions:
  • Are tattoos poisoning us or increasing cancer risk?
  • What’s actually in tattoo ink?
  • Are there any upsides?
• Quotes from viral social media clips reflect both confusion and concern (“...you're constantly being poisoned by the toxins. If I were to go back in time with the knowledge I have now, I would not have the tattoos that I have.” — [00:36])
• Rose lays out the stakes: tattoos are mainstream (1/3 of adults in the US and Australia; 1/5 globally), so any health impact matters.

---

Why Scientists Began to Study Tattoo Ink (05:09-08:36)

• Tattoo ink research is surprisingly new because application has outpaced scientific study.
• Dr. Santiago Gonzalez (University of Lugano) stumbled into tattoo research after using tattoo machines to label mice in experiments.
  • Discovery: Tattoo ink ended up in the mice’s lymph nodes (“...the lymph nodes of the animals are completely full with the ink of the tattoo.” — Dr. Gonzalez [06:28])
  • This led them to follow where ink goes after tattooing.

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What Happens to Tattoo Ink in the Body? (07:25-09:36)

• Ink does not remain solely in the skin:
  • Immune cells (“macrophages”) gobble up ink and can carry it to lymph nodes.
  • This occurs in mice and has been observed in humans’ biopsied lymph nodes.
  • “When you are tattooing your skin, you are also tattooing your lymph nodes.” — Dr. Gonzalez [08:32]
• Most tattoo-induced immune activation is short-lived, but one marker for chronic inflammation (“alarming”) stays elevated for months post-tattoo.

---

Immune Reactions: Common? Dangerous? (09:33-12:21)

• Mouse studies hint at immune system “weirdness,” but more research is needed on long-term human effects.
• Human anecdotes support rare but alarming immune reactions:
  • Severe case: A Polish man lost hair, developed vitiligo, and had to have a tattoo surgically removed ([10:25]).
  • Some rare cases of tattoo ink triggering immune attacks on the eyes resulting in vision loss ([10:36]).
• Larger-scale data:
  • German study: ~9% of tattooed people reported persistent skin reactions a month after getting inked ([11:32]).
  • Most reactions are mild, but unlucky individuals can have bigger issues.

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Tattoo Ink and Carcinogens (12:01-13:00)

• Regulatory clarity is lacking, but it’s known that many inks — especially black inks — contain potentially carcinogenic substances (“Basically soot.” [12:36]).
• Concern: Could these ingredients, or the chronic inflammation, increase cancer risk?

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Sweden’s Groundbreaking Epidemiological Study (13:44-19:37)

• Dr. Christel Nielsen (Lund University) led a large-scale Swedish study using national registries.
  • Focused on two cancer types: skin cancers (especially melanoma) and lymphoma.
  • Compared records of people with these cancers to matched controls, analyzed tattoo status and details.
  • Returned remarkable engagement: “Some still send me postcards. It’s really, really sweet.” — Dr. Nielsen [17:43]
• Initial Results:
  • Tattooed people had a 20% relative increased risk of lymphoma.
  • 30% relative increased risk of melanoma.
  • But, absolute risk rises were small (example: lymphoma risk grows from 2.2% to 2.64%).
    “So the risk on an individual level is small. People shouldn’t be freaking out.” — Dr. Nielsen [18:48]

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Is the Cancer Link Real? (19:37-21:34)

• Not every study finds the same effect, but the largest/strongest (including a similar Danish study) do observe cancer links.
• Confounding factors (e.g., lifestyle differences for tattooed people) are considered, but evidence still points to a possible real, if small, risk due to ink and immune processes.

---

Tattoo Removal: Is It Safer? (21:00-22:28)

• Tattoo laser removal is common, but little is known about its health impact.
  • Laser breaks ink into smaller fragments (“You don’t laser tattoos and they evaporate into thin air... They need to get through the body to get out.” — Dr. Nielsen [21:34])
  • Some breakdown products are more carcinogenic than original ink components (e.g., azo dyes breaking down into carcinogens).
  • “We might set off a cascade of exposure to something that we don’t know what it is, but it might be worse than the original exposure.” — Dr. Nielsen [22:17]

---

Real-Life Benefits: Tattoos & Wellbeing (23:28-26:06)

• Beyond cool factor, Rose introduces Dr. Viren Swami (Anglia Ruskin University), a social psychologist.
  • Tattoos serve as markers of bodily agency and have deep ties to cultures or communities historically treated as “out-groups.”
  • In the U.S., queer women are the most likely demographic to be tattooed (68%) ([24:47]).
  • Tattoos are a form of reclaiming the body, especially for those who experienced marginalization or trauma (“this body is mine.” — Dr. Swami [25:06])
• Psychological studies show positive impacts:
  • People feel happier with their bodies, more unique, and experience less anxiety post-tattoo ([25:36]).
  • Even temporary tattoos (artificial, 2 weeks) yielded self-esteem improvements ([25:48]).
  • Only ~20% of people regret tattoos, meaning 80% don’t ([26:05]).

---

Final Thoughts and Nuance (26:18–27:47)

• Most people aren’t deterred by the small documented health risks.
• Whether to get a tattoo (or another one) is a personal risk/benefit decision, factoring in possible health risks and psychological benefits.
• Studies so far are “good but incomplete” — future research, including long-term global studies, is underway.
• Question remains: Is more ink or bigger tattoos riskier? The answer is uncertain, but the Denmark study found some added risk with more/larger tattoos ([27:12]).
• “We, as a society, will continue to get inked, and then we need to make sure that it’s safe to do it.” — Dr. Nielsen [22:51]

---

Notable Quotes & Memorable Moments

• “When you are tattooing your skin, you are also tattooing your lymph nodes.” — Dr. Santiago Gonzalez [08:32]
• “We saw an increased risk of lymphoma among those with tattoos compared to those who did not have tattoos. Their risk was 20% increased.” — Dr. Christel Nielsen [18:29]
• “So the risk on an individual level is small. People shouldn’t be freaking out.” — Dr. Nielsen [18:48]
• “You don’t laser tattoos and they evaporate into thin air... They need to get through the body to get out the other end.” — Dr. Nielsen [21:34]
• “Being tattooed is a small marker of agency. It says ‘I am allowed to own my own body and do what I want with my body.’” — Dr. Veeran Swami [23:47]
• “After they got their tattoo, people reported being happier with their bodies, appreciating their bodies more, feeling like they were more unique, and feeling lower anxiety about their appearance.” — Dr. Swami [25:36]

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Timestamps for Key Segments

• 00:00–02:01 — Opening theme, what’s at stake, and social media commentary on tattoo toxicity
• 03:39–05:09 — Host and producer discuss personal tattoos and initial health worries
• 05:09–08:36 — Dr. Santiago Gonzalez: how tattoo ink migrates and what that means for health
• 09:33–12:21 — Allergic reactions, immune responses, and rare but severe cases
• 12:01–13:00 — Carcinogenic potential of ink, especially black (“soot”)
• 13:44–19:37 — Swedish epidemiological study: how tattoos may marginally raise cancer risk
• 21:00–22:28 — Problems with tattoo removal, laser breakdown products
• 23:28–25:48 — Psychological benefits: agency, self-esteem, body positivity
• 26:18–27:47 — Conclusion: weighing risks, future research, and cultural significance

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Tone and Flow

Conversational, light-hearted, occasionally self-deprecating, but always rooted in evidence and empathy. The episode balances personal anecdotes (from the team and scientists) with rigorous, large-scale scientific research — clarifying what we know, what we don’t, and what’s still uncertain.

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Bottom Line

Tattoos are not risk-free:

• Ink does move in the body, can provoke immune responses, and emerging data show small but real increases in cancer risk (lymphoma, melanoma) for tattooed people.
• Most cases are mild; severe immune reactions and vision loss are extremely rare.
• Tattoo removal by laser may introduce new risks due to toxic breakdown products.

But tattoos also confer psychological and social benefits:

• Increase agency and self-esteem, particularly for marginalized communities.
• The vast majority of tattooed people do not regret their decision.

The science is still evolving — with several long-term studies underway, our understanding is likely to grow clearer in the next 5–10 years.

Personal risk assessment is key:
“Risk vs. benefit. Benefit looks cool.” — [23:28]
The decision to get inked (or not) remains individual — now better-informed by the evidence.

Transcript

[Rose Rimler]

Hi, I'm Rose Rimler filling in for Wendy Zuckerman. And this is Science versus Today. We are talking about tattoos. Tattoos are more popular than ever, but lately they've been getting some flack. Online. We're hearing that tattoos are toxic. What is a toxic guy tattoo, upper chest, Roman numerals. That is always a toxic guy. Everyone knows one of those guys. No, not that kind of toxic, like poisonous. It turns out tattoos are actually pretty unhealthy for us. You're constantly being poisoned by the toxins. If I were to go back in time with the knowledge I have now, I would not have the tattoos that I have. People are pointing to Tattoo Inc. Saying that it's full of stuff that you don't want in your body.

[Christel Nielsen]

Every single person who has a tattoo

[Rose Rimler]

has metals leaching into the bloodstream.

[Christel Nielsen]

Mercury, lead, nickel, and other harmful heavy metals that will slowly release in your body and adding to your toxic burden daily.

[Rose Rimler]

And ultimately, they say that the consequences can be serious. A new study has found it could increase your risk of developing cancer. 21% chance of getting a malignant lymphoma with even small tattoos. And if this risk is real, it would affect a lot of people. According to surveys in the US And Australia, a third of adults are tattooed. And globally that number is one in five. So are these people making a terrible mistake? If you get a tattoo, are you poisoning yourself and upping your risk of cancer? And finally, has science found any benefits to getting inked? Because when it comes to tattoos, there's a lot of upper chest Roman numerals. But then there's science. Science versus Tattoos is coming up after the brink.

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[Rose Rimler]

Welcome back. We are here to talk about tattoos. I'm Rose Rimler and I'm here with some science versus editor and tattoo haver Blythe Terrell. Hi.

[Blythe Terrell]

Blythe Harrow's famed tattoo haver. I will say.

[Rose Rimler]

So how many tattoos do you have? Where are they? Spill it.

[Blythe Terrell]

So the first one I got, I got with my good friend. Like when I was 18, we both got flowers. It's just like, I'm 18. I have a flower. My husband and I have one that's kind of like I love you in sign language. Stylized. I have a stylized double helix on my ankle.

[Rose Rimler]

Very nerdy, very on theme.

[Blythe Terrell]

And then my other one is the Batman logo, but it is the 1960s Batman. I've always kind of been curious about it.

[Rose Rimler]

Why? Why Batman?

[Blythe Terrell]

So my initials are B, A T. And so it's been like a running joke.

[Rose Rimler]

Okay. But you're the Batman

[Blythe Terrell]

revealed on this podcast.

[Rose Rimler]

Have you ever worried about your tattoos?

[Blythe Terrell]

I mean, my mom worried that I wouldn't get jobs, but, like, health wise? I mean, I guess only to the extent that I was like, okay, is this guy like a clean needle out of the package? But beyond that, no. Has never come up for me.

[Rose Rimler]

Yeah. And I was pretty surprised myself when I saw this stuff pop up online about tattoos being toxic. I don't have any tattoos myself, but I know so many people who do. So I really want to know, is this true or is this just bs?

[Blythe Terrell]

Yeah. Very curious to know what you found.

[Rose Rimler]

So, you know, obviously tattoos have been around thousands of years, but interestingly, scientists have only recently begun to study how the tattoo ink interacts with our biology. This is kind of on the newer side of things. Scientists like Santiago Gonzalez, he is a toxicologist and immunologist at the University of Lugano in Switzerland.

[Santiago Gonzalez]

Actually started by chance. So we were not primarily oriented on the tattoo.

[Rose Rimler]

Here's what happened. Santiago needed to label mice for an experiment they were doing about the immune system. The way they had been doing that was putting a tag on the mouse's ear, like tagging their ears, which is very common. Yeah.

[Santiago Gonzalez]

But I never like it because it's a bit Heavy. And the animals is a bit annoying for the animal.

[Rose Rimler]

So instead of tagging their ears, the scientists in his lab decided they were going to try tattooing the animals in order to, like, mark them.

[Santiago Gonzalez]

We basically have a tattoo machine which is exactly the same as the tattoo, that machine that is used by all the tattoo artists, and we just do it normally.

[Rose Rimler]

Like, is it, like, teeny, teeny, tiny?

[Santiago Gonzalez]

Yeah, it's very small. So obviously, you have to be very, very careful.

[Rose Rimler]

So they're chugging along, tattooing their mice to do their next experiment, which all seemed to work fine. But then something unexpected happened.

[Santiago Gonzalez]

My students told me, you know, the lymph nodes of the animals are completely full with the ink of the tattoo.

[Blythe Terrell]

Oh, gross.

[Rose Rimler]

And just as a reminder, lymph nodes are structures in the body that are part of the immune system. They filter out lymph, which is a fluid that comes from the blood. So Santiago's team was looking at one of the lymph nodes in the mouse's leg near its foot, which is what had been tattooed, and they found that it got stained with the tattoo ink.

[Blythe Terrell]

Okay, that's not. Doesn't sound good.

[Rose Rimler]

It's not what they expected, and it kind of messed up that experiment.

[Blythe Terrell]

Right? That's not what they were studying.

[Rose Rimler]

Right? It's not what they were studying. They're just using the tattoos to label the mice for another experiment. But after seeing this, they decided to do an experiment where they tattooed the mice and then watched where the ink went in a more controlled way. Okay, so we did all this again and then took photos of the lymph nodes two months later. So let me show you.

[Blythe Terrell]

Oh.

[Rose Rimler]

Oh, yeah.

[Blythe Terrell]

You can really see, like, it's really. You can really see the ink in there.

[Rose Rimler]

Like, it's bright. Yeah, it's a few different colors of ink. And you can see, like, when one mouse has a pretty bright blue lymph node, like, bulbous, little goofy thing.

[Blythe Terrell]

So how did that happen?

[Rose Rimler]

Well, okay, so your body has these white blood cells, they're called macrophages, that go around gobbling up stuff that they think shouldn't be there. So this is typically, like, bacteria, broken bits of cells. When you get a tattoo, macrophages in your skin, they go around and they slurp up some of that ink, and it turn. But they're also bringing that ink to the lymph nodes. And scientists have also seen this in people. We've had case studies documenting it. Like, if someone with tattoos goes in to get their lymph node biopsied, for whatever reason, pathologists will sometimes find ink in the lymph node. And Santiago's team also found this when they looked at lymph nodes from people, which led him to conclude, when you

[Santiago Gonzalez]

are tattooing your skin, you are also tattooing your lymph nodes.

[Blythe Terrell]

Okay, so we have tattooed lymph nodes, but does that, like, does that automatically equal some kind of a problem?

[Rose Rimler]

Well, it's possible. I mean, if the lymph node is involved, that means the immune system is involved in some way. So Santiago's team also checked levels of immune markers in the mice's bodies to see if they were elevated. That would suggest that they were stressed out. Basically, these are molecules that are part of the body's stress response to injuries or illnesses. And he did find that these molecules increased in both the lymph taken from the lymph node and in the mice's blood. But most of that activation went back to normal after a week or so from getting the tattoo. Which makes sense. Like, of course, you'd have a temporary inflammatory response to a bunch of needles in your skin. But there was one exception. A molecule associated with chronic inflammation. It's actually called alarming. Great.

[Blythe Terrell]

Yeah. What was the alarm in doing, Rose?

[Rose Rimler]

It was alarmed. It was raised even two months post tattooing. Which Santiago argues should have been past the initial healing phase of the tattoo.

[Blythe Terrell]

Uh huh. Okay, so how worried should we be about that?

[Rose Rimler]

Well, you know, Santiago's study was kind of exploratory. It showed some hints of some immune system weirdness in mice. It wasn't looking at long term issues in real people. So zooming out to other studies, we do start to see that this activation of the immune system might be a problem for some people. I read this case study. A guy from Poland, he had a full blown immune reaction to his tattoo. Four months after he got it, he lost his hair, he developed vitiligo.

[Blythe Terrell]

What's that?

[Rose Rimler]

That's like a skin. A change in the color of your skin.

[Blythe Terrell]

Okay.

[Rose Rimler]

And he had to get the tattoo essentially cut out of his arm.

[Blythe Terrell]

Whoa.

[Rose Rimler]

There's another series of cases that was published recently in Australia about people who got this allergic reaction to their tattoo ink, and it attacked their eyes.

[Blythe Terrell]

Oh, my God.

[Rose Rimler]

And some of them even had vision loss. Those examples are extreme, and they're not that common. But in general, we do see a lot of allergic reactions to tattoos. Just typically, it's confined to the skin.

[Blythe Terrell]

Actually, you know what that makes me think of, Rose?

[Rose Rimler]

Huh.

[Blythe Terrell]

So the other day, I was sitting with my husband and he looked at me and he was like, do your tattoos ever itch? And I was like, no. Do your tattoos ever itch? And you know what else, Rose? He has some, like, immune system stuff going on a little bit.

[Rose Rimler]

Another autoimmune system thing.

[Blythe Terrell]

So I kind of had this feeling, as you say this, I'm like, oh, I wonder if, like, suddenly there' this change and, like, the itchy. Like, Jack's tattoos are getting a little itchy. I wonder if it's related.

[Rose Rimler]

Okay, interesting. Well, the best numbers I could find on how common this is, this, like, sort of skin reaction to tattoos. It comes from a survey of people with tattoos in Germany, and it found that about 9% of people reported persistent skin problems at least a month after they got their tattoo. Hmm.

[Blythe Terrell]

Okay.

[Rose Rimler]

And so it sounds like he might be in that unlucky sliver of people.

[Blythe Terrell]

Lucky. Lucky in love, unlucky in tattoos, obviously. Obviously.

[Rose Rimler]

So this happens to a fraction of unlucky people. 9% in that German study. But there are other reasons to be concerned about tattoo ink. That's more universal for everyone who gets tattooed. One of those things is the fact that a lot of tattoo ink contains chemicals that we think are possibly carcinogenic.

[Blythe Terrell]

Hmm.

[Rose Rimler]

And that includes black ink. And, you know, a lot of your tattoos are black. I noticed.

[Blythe Terrell]

I think they're. Yeah, most of them are black. Okay, great. What are you going to tell me about black ink, Rose? Carcinogenic black ink is basically soot.

[Rose Rimler]

Sorry.

[Blythe Terrell]

Great. So it's like, yeah, like if I were a chimney sweep instead of a podcaster. That's the. Is that what's going on here?

[Rose Rimler]

Yes. Right. But this is what makes some people worried that tattoos might cause cancer, and we're gonna need some more science to figure that out.

[Blythe Terrell]

Okay.

[Rose Rimler]

So we're gonna have to go to Sweden.

[Blythe Terrell]

I'm ready.

[Rose Rimler]

All right.

[Blythe Terrell]

I was ready.

[Rose Rimler]

Is coming up after the break.

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[Rose Rimler]

Welcome back. We're talking about tattoos today, and I'm here with Blythe.

[Blythe Terrell]

Terrell.

[Rose Rimler]

Hi, Blythe.

[Blythe Terrell]

Hey, Rose.

[Rose Rimler]

So it turns out there are some reasons to be concerned about tattoos. We know that the ink doesn't just stay put, static in our skin. It's actually interacting with our immune system, getting into our lymph nodes. We know that some of the ink might be bad for us, might be even carcinogenic. But we want to know, like, what are the consequences?

[Blythe Terrell]

Right. Besides just you feeling superior to me for not because you don't have tattoos and I do.

[Rose Rimler]

We know that people without tattoos are better, but are they healthier? I spoke about this with Christel Nielsen. She works at Lund University in Sweden. She is an epidemiologist who focuses on environmental toxins, typically stuff like forever chemicals. But a few years ago, she got curious about potential toxins in tattoos.

[Christel Nielsen]

And I might have one or two tattoos myself. So that triggered the interest.

[Rose Rimler]

What do you have?

[Christel Nielsen]

I have a dragon on my arm. And I was awesome. And I was young in the 90s, so I might have a Chinese sign on my lower back.

[Rose Rimler]

A Chinese character on your lower back?

[Prime Obsession Advertisement Voice]

I'm not.

[Rose Rimler]

I'm just laughing because.

[Christel Nielsen]

Yeah, yeah, you laugh. It's the stereotype. But I don't have a tribal. I have to say that.

[Rose Rimler]

What does the Chinese character mean?

[Christel Nielsen]

It's supposed to mean horse because I'm born in the year of the horse. But I showed it to my daughter's friend who knows Chinese, and she said, I've never seen that sign before, so I don't know what it means.

[Blythe Terrell]

This is the classic tattoo horror story of the 90s. Yeah. So she's relatable is what I'm saying.

[Rose Rimler]

Yes, she's very relatable. So she decided to learn Chinese. No, no, she didn't. She decided to look into tattoos and health.

[Blythe Terrell]

I was ready to go with you on that journey.

[Rose Rimler]

She zoomed in on cancer for the reasons we talked about before, the potential carcinogenic ink. And also we know that chronic inflammation can lead to cancer. So she dove into that beautiful Scandinavian public health data that we love so much here at Science versus In Sweden,

[Christel Nielsen]

we have this very, very, in terms of research, useful national registries where we all end up whether we like it or not. So it's. It has full population coverage, and especially for cancer, we have the National Cancer Registry. So if you get diagnosed with cancer in Sweden, any cancer, you will end up there.

[Rose Rimler]

So she and her team decided to focus on two types of cancer that they could see plausibly being connected to. Tattoos, skin cancers, including melanoma. It's kind of obvious. But also lymphoma. That's cancer of the lymph system.

[Blythe Terrell]

Right. Because we know that the ink is in the lymph system, so that makes sense. Okay, got it.

[Rose Rimler]

And so they pulled the records of everyone in Sweden who had been diagnosed with those cancers between the ages of 20 and 60, and then they set out to find who among them had tattoos.

[Christel Nielsen]

So we contacted all of them, and, I mean, lymphoma is a severe disease, so not everyone who were diagnosed 10 years ago were still alive.

[Rose Rimler]

Right.

[Christel Nielsen]

And in that case, we contacted their next of kin.

[Rose Rimler]

I see.

[Christel Nielsen]

With the main point then, of understanding whether the relative had had tattoos or not.

[Rose Rimler]

And they also gathered a group of matched people who did not have cancer, sort of like matched controls. And they sent out questionnaires to them as well. A lot of lifestyle stuff, but also lots of questions about tattoos. Not just, do you have a tattoo? But how many do you have? How big is it? When did you get it? Where'd you get it? All that kind of stuff. People really got excited about this. They sent Christel, like, all these emails and stuff, like, they wanted to tell her all about their tattoos.

[Christel Nielsen]

It's nice to get to know your participants in a way. And some still send me postcards. It's really, really sweet.

[Rose Rimler]

So the data started coming back, and Christel was working closely with one of her co authors. But this is during the pandemic. They weren't together that much. So one day, Christel found herself just crunching the data alone.

[Christel Nielsen]

I was, you know, in my house. It was just me, and I had the data there, and I just. I just needed to have a look. And then there were the preliminary results, and I just threw myself at the phone and told her that, well, we might actually have something here. Whoa.

[Blythe Terrell]

Oh, no. Yeah.

[Rose Rimler]

So she found something when it came to cancer risk. So first lymphoma.

[Christel Nielsen]

We saw an increased risk of lymphoma among those with tattoos compared to those who did not have tattoos. Their risk was 20% increased.

[Rose Rimler]

They also found about a 30% increased risk of melanoma.

[Blythe Terrell]

Wow, that seems big. Is that big?

[Rose Rimler]

Well, here's Cristel on that.

[Christel Nielsen]

So we're talking about relative risk increases. So the risk on an individual level is small. People shouldn't be freaking out.

[Blythe Terrell]

Mm. Because it's like. It's that sort of situation where a 20% increase risk is serious, but the original risk might be very small. So the new risk, even 20% higher is still not, like, astronomical. Is that the idea?

[Rose Rimler]

Exactly. So, like, in the U.S. according to the National Cancer Institute, the absolute risk of getting lymphoma is about 2.2%. So if we apply Cristel's finding to that, it Suggests that a tattoo might make that risk go from 2.2 to 2.64%. And then for melanoma, it would be, like, starting at 2.2%, going to 2.9%, like, sort of for the average person.

[Blythe Terrell]

Okay. I mean. Right. So it's not a thing, obviously.

[Rose Rimler]

Yeah.

[Blythe Terrell]

And so maybe if you're a person who's already, like, at increased risk or whatever, that's something. Maybe you want to factor that in.

[Rose Rimler]

Exactly. And there are a couple other studies that have looked into this, and not all of them find this link to cancer, but the strongest and biggest studies do find this link, like a similar one that was done in Denmark.

[Blythe Terrell]

Well, but what about. Is there any reason to think there might be some confounders? Do people who have tattoos tend to have a different kind of lifestyle or be more likely to party or engage in other behaviors?

[Prime Obsession Advertisement Voice]

Rose.

[Blythe Terrell]

That might contribute to cancer risk or that kind of stuff?

[Rose Rimler]

So these studies do try to adjust for that as best they can. But, yeah, it's probably not perfect. And there is some evidence that people who have tattoos might do some, on the whole, are more likely to do some risky behavior compared to people who don't have tattoos. So smoking is something that has come up in the literature. The thing is, these cancers are not particularly associated with smoking.

[Blythe Terrell]

Okay, so it sounds like you think there's something here.

[Rose Rimler]

Yes, I do, and I do, partly because I think the studies, Kristel's and the other city from Denmark are good studies. And also, it seems like we have a mechanism that's plausible. It does make some sense.

[Blythe Terrell]

Rose. Should I get all my tattoos removed? Should I get. Cause you can, right? There are ways to get tattoos removed.

[Rose Rimler]

Yeah, you can get them removed with lasers. And you might want to do that if you're freaked out about what I just said, or you got a Chinese character on your lower back and you actually don't know what it means. And. And in fact, outside of this, studies do find that something like 20 to 25% of people regret at least one tattoo. Chrisal says the thing about that is, for as little as we know about the effect of tattoo ink on the body, we know even less about what happens when we shoot lasers at tattoos.

[Christel Nielsen]

So what people need to know is, I mean, don't laser tattoos, and they evaporate into thin air. I mean, that's not what happens. They need to get through the body to get out in the other end.

[Rose Rimler]

Basically, the laser blasts the ink into smaller fragments that the immune system then can go and clean up. But you're still, like, getting your immune system to, you know, you're triggering an immune response, and you're also changing the molecules. And some of those are worse than the original molecules in the ink. So, for example, we know that a lot of the colors in tattoo ink are made with nitrogen groups called azos. And when azos are broken apart, they can form compounds that we know are carcinogenic.

[Christel Nielsen]

So we might set off a cascade of exposure to something that we don't know what it is, but it might be worse than the original exposure might be.

[Rose Rimler]

I mean, there's a lot we don't know. We should be getting more information about tattoos generally over the next five or ten years. Cristel is going to keep studying people. She's got this cohort, you know, she's gonna keep studying them. There's another project that's backed by the World Health Organization that's getting off the ground following people with tattoos over a number of years. Okay, so we're gonna find out more about tattoos and health.

[Christel Nielsen]

I think that we, as a society, we will continue to get inked, and then we need to make sure that it's safe to do it.

[Blythe Terrell]

Absolutely. And I think what we do on the show, right, is like, try to give you the information to, like, make that decision for yourself. You know, we're not cops. But even when I think about it, I' I knowing all this, like, I don't know, you know, like, maybe I still would have gotten my tattoos. Cause I like them. You know what I mean? Like, I'm not sure if knowing this would have been quite enough for me to be, like, never, right?

[Rose Rimler]

Well, yeah. I mean, and the thing is, like, with anything that we talk about, it's always like, risk versus benefit.

[Blythe Terrell]

You know, benefit looks cool.

[Rose Rimler]

No, there are real benefits, Blythe. It's more than just looking cool. And I have one final guest to introduce you to to tell us a little bit more about that. His name is Veeran Swami. He is a professor of social psychology at Anglia Ruskin University.

[Veeran Swami]

In the UK Being tattooed or being able to get a tattoo is a small marker of agency. Says I am allowed to own my own body and do what I want with my body. Historically, essentially, tattoos were the preserve of what psychologists have called out groups. And out groups. We simply mean marginalized communities.

[Rose Rimler]

So, like, in the west, and in communities colonized by the west, tattooing has been associated with being in an out group. Like think of sailors in the 1700s. But it's mainstream in other parts of the World like in Polynesia. And even though today in the west, tattoos are not as stigmatized, researchers still find an echo of that motivation. So this is interesting. The demographic in the US that is most likely to get tattooed, this is according to a Pew Research survey from a few years ago. Queer women, huh? 68% of people who identify as queer women have at least one tattoo.

[Blythe Terrell]

Interesting.

[Rose Rimler]

And that makes a lot of sense to Viren. It goes back to the idea of being part of an out group.

[Veeran Swami]

I think any community that has a history of marginalization will try and reclaim the body in some way. It's also the same reason why some researchers have talked about how women who have been. Who have had a history of sexual or physical abuse tend to get tattooed again. It's a way of reclaiming the body and saying, this body is mine.

[Rose Rimler]

And we do have some evidence that getting tattooed can help people feel better about themselves. A few years ago, Viren went to a tattoo shop in London, and he surveyed people before and after they got their first tattoo and also followed up with them a little bit later. He did stuff like he was assessing their self esteem. He asked them, how do you feel about your body? How do you feel about how you look? And it turns out that after they

[Veeran Swami]

got their tattoo, people reported being happier with their bodies, appreciating their bodies more, feeling like they were more unique as a result of getting tattoos and feeling lower anxiety about their appearance.

[Rose Rimler]

Another study found this too. This study actually had college students design a temporary tattoo that an artist painted on them. It lasted a couple weeks, and they measured their, like, self esteem and how they felt before and after that temporary tattoo. And it did. Also gave them a boost.

[Blythe Terrell]

Oh, that's fun.

[Rose Rimler]

And I think it's telling that most people don't regret their tattoos even years later. Remember that stat I told you earlier? It's like maybe 20% of people regret their tattoos, and that means 80% don't.

[Blythe Terrell]

Yeah, totally. I'm among the 80% rose.

[Rose Rimler]

Okay. Well, I was gonna ask you, how are you feeling about tattoos after all that information and your husband's itchy arm?

[Blythe Terrell]

Well, yeah, I guess I should tell him to keep an eye out for anything else that might go on that's unnerving here. Right? But yeah, you know, I mean, I think for the. Generally speaking, I go into things thinking like, ah, it's an Internet meme. People are, you know, freaking out or whatever. It's toxic. Don't do it. And so I expect those things to be kind of not true. That's my baseline. I'm skeptical, I guess. So I think it's really useful to know that maybe there is something there. I don't know. Overall, I guess it doesn't freak me out about the tattoos that I have now.

[Rose Rimler]

Yeah. But let me ask you this. Would you get another one?

[Blythe Terrell]

I don't know.

[Rose Rimler]

Do you want to? Do you have any planned?

[Blythe Terrell]

I had been thinking about it. I've had a particular stegosaurus in mind for a while. Of course. Yeah.

[Rose Rimler]

Well, I will say one thing we didn't talk about was are you more at risk if you have more tattoos?

[Blythe Terrell]

Yeah. Well, that's. Yeah.

[Rose Rimler]

And Christel's study found no, but the Denmark study found yes or like bigger tattoos. And Crystal actually thinks that her finding was sort of an artifact of the way she asked the question. So she thinks it's very possible the more tattoos or the more ink, if you get like a really ink filled tattoo, very likely could have a higher risk associated with it. We don't have all the receipts for that. Something to consider.

[Blythe Terrell]

Okay, I can do that, Rose. I can consider it. Consider it. Thank you so much.

[Rose Rimler]

Thank you. And that's Science versus. Blythe. You should know that there are 77 citations in this week's episode.

[Blythe Terrell]

Wow. Okay.

[Rose Rimler]

And you can tell folks where to find them?

[Christel Nielsen]

Blive.

[Blythe Terrell]

Yes. You can find them in our transcript which we link to in our show notes. All right.

[Rose Rimler]

This episode was produced by Rose Rummler with help from Blythe Turrell, Akedi Foster Keys, Meryl Horne and Michelle Dang. Wendy Zuckerman is our executive producer. We're edited by Blythe Terrell. Fact checking by Diane Kelly. Mix and sound design by Bumi Hidaka and Bobby Lord. Music written by Bobby Lourd, Bumi Hidaka. So Wylie, Emma Munger and Peter Leonard. Special thanks to all the experts we spoke with for this episode, including Dr. Sinia Clemenson, Professor David Kreibel, Dr. John Swierk, Natasha Chinotti, Dr. Sandrine Henri, Professor Chris Lynn and Tricia Allen. Science Versus is a Spotify Studios original. Listen for free on Spotify or wherever you get your podcasts. Follow us and tap the bell for episode notific.