Sure, the study would be best if we did a randomised double blind study on a sample of 100 people that all are going to get a tattoo anyway but that doesn’t make the mouse study irrelevant.

Mice and humans, although very different in appearance have biomechanics that are very similar. For every human study you could make a 20 mouse studies with the same funding so you could do a lot more exploration.

This study found something, notably that ink in the blood affected the immune system. This just means that future studies are needed like injecting people with tattoo ink and blood samples diagnosis after tattoo to see how much ink is in the blood. If confirmed this will push tattoo ink manufacturers to develop a new ink that eliminates the effect and we can all enjoy safer more effective tattooing.

This study is not flawed, it’s pushing human knowledge forward like it always does.

• adding “in mice” to the title;

Similarly, human immune cells previously exposed to ink also showed a weakened response to vaccination.

The full paper is here and, as usual, it’s hardly anything and decontextualized in order to get a publishable result.

This one is so bad that it doesn’t use established baselines or do any form of statistical analysis on the results instead opting for their own “baseline” measurements using very small sample sizes. It also plays a smoke and mirrors game where it shows a result for short term immunological response and then uses that to insinuate the ‘slightly reduced but still likely well within the error of the poor control’ long term effects are worth noting.

Other major flaws:

• As others have mentioned, mice are a terrible model for this as their skin is very thin and proper tattooing is near impossible.
• They mention verifying with human cadavers but don’t include any data from those.
• There was no control group, the baseline was an untreated mouse, not one with an acute foot trauma.
• Mice age very quickly, best I can tell the immunological markers weren’t age controlled. 2 months out of a <2 year lifespan is a lot of aging. Again, if there was a proper control to measure against.
• The obsfucation of the raw data into cheesy and unreadable box and whisker plots is hella suspicious.

At best it’s a very poorly communicated and poorly designed experiment but I suspect that’s due to it result hunting.

And yet, this single study has already pushed through the news cycle in multiple directions, thanks to its dangerously deceptive headline.

It doesn’t matter if it’s gets disproven in later studies, the damage has been done.

What the hell? Was this even peer reviewed?

Human subjects are crazy to work with for a few reasons

1. People don’t follow instructions perfectly
2. Research subjects often don’t take the research project very seriously.
3. It’s not uncommon to have dropouts, thus you either have to find more subjects or have less data.
4. It’s impossible to know what the subjects are doing to cause data variability (diet, vices, etc)
5. You can’t lock subjects in a room and force them to eat and drink the same food every day.
6. There’s a financial (time) penalty to many research studies that can get in the way of enthusiastic participation.

Laboratory mice literally live 5 to a cage with almost no diet variability, in a controlled environment. Yes shit does happen with research mice, but it’s something that is easy to control overall.

Honestly, I think that shitty science reporting like this is fuel for the normie to science skeptic pipeline.

Absolutely! and having tattoos I care extra… the devil is always in the details

In the society we live in, I’d guess the difference is minuscule so they hide the details to justify the headline

Anecdotally, I live in Canada and tons of people have tattoos; health benchmarks are pretty decent here even if politicians have been trying really hard to dismatle our healthcare system… I feel we would have seen/suspected this before if it were significant (I work in healthcare)

What the hell? Was this even peer reviewed?

Please spare us with AI generated images.

If only there was a place where humans who have a tendency to get tattoos are in cages for an exrended period of time with a relatively consistent, trackable food intake, and constantly tracked behaviour. Humans who might even be motivated by privileges to volunteer for such studies.

Surely someone could check this by doing a statistical analysis of cancer patients with tattoos vs how many of the general population has tattoos?

Please spare us with AI generated images.

The full paper is here and, as usual, it’s hardly anything and decontextualized in order to get a publishable result.

This one is so bad that it doesn’t use established baselines or do any form of statistical analysis on the results instead opting for their own “baseline” measurements using very small sample sizes. It also plays a smoke and mirrors game where it shows a result for short term immunological response and then uses that to insinuate the ‘slightly reduced but still likely well within the error of the poor control’ long term effects are worth noting.

Other major flaws:

• As others have mentioned, mice are a terrible model for this as their skin is very thin and proper tattooing is near impossible.
• They mention verifying with human cadavers but don’t include any data from those.
• There was no control group, the baseline was an untreated mouse, not one with an acute foot trauma.
• Mice age very quickly, best I can tell the immunological markers weren’t age controlled. 2 months out of a <2 year lifespan is a lot of aging. Again, if there was a proper control to measure against.
• The obsfucation of the raw data into cheesy and unreadable box and whisker plots is hella suspicious.

At best it’s a very poorly communicated and poorly designed experiment but I suspect that’s due to it result hunting.

Thanks for chiming in, but I’m not sure I understand the implications. It’s not trustworthy ? I shouldn’t listen to the conclusions ?

The implications are the variables are conflated and the conclusions are overblown.

It should come as no surprise that acute trauma and injecting a foreign substance would cause a relatively significant immunological response. The issue is that for the “chronic phase”, which is where the novelty of this research lies, the evidence shown is far from difinitive compared to the story being told and what results are shown aren’t overly significant.

Even if you 100% believe the paper the conclusion is that the effect of getting tattooed is, arguably, similar to catching the flu once. However, the paper itself tried to obfuscate that so they have a more impactful result and the marketing/outreach/media site that was linked here doubles down on it trying to sell the story of “tattoos==illness and death”!!!

Study

The researchers discovered that once a tattoo is made, the ink rapidly travels through the lymphatic system and, within hours, accumulates in large quantities in the lymph nodes — key organs of the body’s defense system. Inside these nodes, immune cells called macrophages actively capture all types of pigment. This ink uptake triggers an inflammatory response with two phases: an acute phase lasting about two days after tattooing, followed by a chronic phase that can persist for years. The chronic phase is particularly concerning because it weakens the immune system, potentially increasing the susceptibility to infections and cancer. The study also showed that macrophages cannot break down the ink like they would other pathogens, wich causes them to die, especially with red and black inks, suggesting these colors may be more toxic. As a result, ink remains trapped in the lymph nodes in a continuous cycle of capture and cell death, gradually affecting the immune system’s defensive capacity.

The study found that tattooed mice produced significantly lower levels of antibodies after vaccination. This effect is likely due to the impaired function of immune cells that remain associated with tattoo ink for long periods. Similarly, human immune cells previously exposed to ink also showed a weakened response to vaccination.

Study

The researchers discovered that once a tattoo is made, the ink rapidly travels through the lymphatic system and, within hours, accumulates in large quantities in the lymph nodes — key organs of the body’s defense system. Inside these nodes, immune cells called macrophages actively capture all types of pigment. This ink uptake triggers an inflammatory response with two phases: an acute phase lasting about two days after tattooing, followed by a chronic phase that can persist for years. The chronic phase is particularly concerning because it weakens the immune system, potentially increasing the susceptibility to infections and cancer. The study also showed that macrophages cannot break down the ink like they would other pathogens, wich causes them to die, especially with red and black inks, suggesting these colors may be more toxic. As a result, ink remains trapped in the lymph nodes in a continuous cycle of capture and cell death, gradually affecting the immune system’s defensive capacity.

The study found that tattooed mice produced significantly lower levels of antibodies after vaccination. This effect is likely due to the impaired function of immune cells that remain associated with tattoo ink for long periods. Similarly, human immune cells previously exposed to ink also showed a weakened response to vaccination.

Please spare us with AI generated images.