Never have I ever seen RFK Jr do something and immediately wanted to get on the bandwagon. I am apparently in the minority. Because when the Health Secretary was photographed squirting fish tank cleaner into his water on a plane, the next logical step for swathes of devoted followers on the internet was to do exactly the same thing. Their morning smoothies turned blue, and they posted a blue tongue selfie to prove their commitment to the cause. Methylene blue is, to be precise about this, an antifungal dye. It has been used since the 1890s, primarily in medical settings for very specific purposes, and in aquariums to treat fungal infections in fish. It is the thing you put in the tank when your goldfish is unwell. It is not, and this feels like something that should not need saying in the year of our Lord 2026, a cognitive enhancer you squirt into your Evian at 30,000 feet because a cabinet member did it first. And yet. The blue tongue selfie has become a wellness flex. Fitness influencers with hundreds of thousands of followers are posting photographs of their azure mouths alongside claims that methylene blue boosts mitochondrial (the powerhouse of the cell!) function, fights brain inflammation, enhances memory, and may even protect against Alzheimer's and Parkinson's. Ben Greenfield, is a fitness influencer with half a million Instagram followers, called it "one of my favourite nootropics." He definitely did not just read one 2015 study and extrapolate wildly from it. The doctors have some thoughts about all of this, and the thoughts are not positive. But between the RFK Jr plane photograph and the doctors' notes, an entire wellness economy has sprung up around a fish tank disinfectant, and it is turning people's tongues blue in the name of biohacking, which is a sentence that would have been incomprehensible ten years ago and is now just roaming free on TikTok. bengreenfieldfitness Methylene blue, chemical name methylthioninium chloride, was first synthesised in 1876 by German chemist Heinrich Caro, who was looking for a textile dye and accidentally produced one of the first synthetic drugs in history. It was adopted into medicine almost immediately, initially as a treatment for malaria, and later for a condition called methemoglobinemia, where the blood loses its ability to carry oxygen effectively. It is still used for this purpose today, administered intravenously in hospital settings by doctors who know precisely what dose is appropriate for a specific patient with a specific diagnosis. It has also been used as a surgical dye to mark tissue, as a treatment for urinary tract infections in the mid-twentieth century before better options became available, and in some psychiatric research in the 1980s exploring its effect on cognitive function. It crosses the blood-brain barrier, which is why researchers became interested in its neurological potential, and it does have a measurable effect on mitochondrial function in laboratory conditions. Are you in a laboratory? None of this makes it a supplement you should be buying from a wellness website and adding to your water bottle. The leap from "has legitimate medical applications administered by doctors in controlled settings" to "drink this fish tank chemical every morning for brain gains" is not a small one. It is, in fact, the entire distance between medicine and wellness culture, which is a gap that has been producing increasingly creative disasters for several years and shows no signs of narrowing. David Clode The current enthusiasm for methylene blue traces back, as these things often do, to a single study that has been dramatically misread by everyone who has cited it on social media since. In 2015, Dr. Kan Cao at the University of Maryland published research on methylene blue's effects on cells affected by Hutchinson-Gilford progeria syndrome, a catastrophic and fatal premature ageing disease that affects children. The study found that methylene blue had anti-ageing properties in the specific cellular context of this rare condition. It was a legitimate piece of research about a devastating disease, conducted in a laboratory, involving cells, not healthy adults looking to optimise their morning routine. The wellness internet picked up "anti-ageing properties" and ran. By the time the claim had travelled through several layers of influencer interpretation, the nuance of "cells affected by a fatal childhood disease in a laboratory setting" had been shed entirely, and what remained was "methylene blue reverses ageing," which is not what the study said, not what Dr. Cao claimed, and not supported by any subsequent research in healthy human populations. Phantom. Dealzz This is the standard mechanism of wellness misinformation, and researchers at the University of Chicago have been tracking it with increasing alarm. A study published by UChicago researchers, who systematically analysed health information on TikTok, found that nearly half of the videos they examined contained non-factual information, with the majority of misleading content coming from non-medical influencers. "There is high-quality and factual information out there on social media platforms such as TikTok, but it may be very difficult to distinguish this from information disseminated by influencers that can actually be harmful," said Christopher Roxbury, surgeon and senior author of the paper. The methylene blue conversation is exactly this dynamic in action. Magnific The claims circulating about methylene blue on TikTok and Instagram cover a range that would be impressive if it were not so alarming. Enhanced mitochondrial function. Neuroprotective effects against brain inflammation; Increased memory and cognitive function; Anti-ageing benefits; Metabolic boosting; Covid-19 treatment. The list reads like a ChatGPT ad for a new placebo product. Greenfield's post to his hundreds of thousands of followers described methylene blue as offering benefits that "include enhanced mitochondrial function, neuroprotective effects against brain inflammation, increased memory and cognitive function, enhanced effects of light and oxygen therapies, and much more." The "and much more" at the end of a list of unsubstantiated medical claims is doing a lot of work there. Ann Deerman Other users have gone further, describing it as a potential therapeutic for Alzheimer's, Parkinson's, and dementia, a claim that has a slightly more complicated relationship with the evidence. There is genuine research into methylene blue's effects on tau protein, which is implicated in Alzheimer's, and some clinical trials have been conducted. Those trials have so far produced mixed results, with a 2016 trial of a methylene blue derivative for Alzheimer's failing to show significant benefit in the primary outcome measures. The pharmaceutical company running the trial reanalysed the data and claimed some benefit in a subset of patients, a move that generated lots of scepticism in the scientific community. "Potential therapeutic being investigated in clinical trials" and "drink this to prevent dementia" are not the same sentence, but they have been collapsed into one on approximately ten thousand TikTok videos. Magnific Hussain Abdeh, superintendent pharmacist at Medicine Direct, spoke to The Independent about the trend. "There is a universe of difference between a health and fitness influencer and a qualified medical professional. Viewers should not take medication tips from them. You should only take medicine that has been recommended specifically for you by a certified doctor or pharmacist." "While it is true that methylene blue has been used in some medical treatments, this is not a widely prescribed medicine, and these treatments will have been prescribed by a qualified doctor. This disinfectant can be toxic if taken in large doses, so taking an unregulated amount can be very dangerous. Furthermore, it may also interact with other medicines you are taking, which could make your medication less effective or increase the risk of side effects." The interaction risk is the one that deserves more attention than it is receiving in the wellness conversation. Methylene blue is a monoamine oxidase inhibitor, which means it affects the breakdown of serotonin in the brain. When combined with antidepressants, particularly SSRIs and SNRIs, this interaction can cause serotonin syndrome, a potentially life-threatening condition involving agitation, confusion, rapid heart rate, high blood pressure, and, in severe cases, seizures and loss of consciousness. This is not a theoretical risk buried in a package insert. It is a documented clinical phenomenon that has caused serious harm in patients who received methylene blue in medical settings while on antidepressants, which is why anaesthesiologists now screen for antidepressant use before administering it surgically. The wellness influencer posting a blue tongue selfie is not screening their audience for antidepressant use before recommending the product. The person watching the video and deciding to try it is not consulting a pharmacist about interactions. This is the gap that Abdeh is describing, the distance between a medical context where risks are managed and a social media context where they are invisible. Thomas Park Methylene blue is not the first fish tank chemical to acquire wellness credentials, and it will not be the last borderline substance to travel from aquarium supply store to supplement stack via TikTok. Colloidal silver, another product with legitimate historical medical uses and a long track record of being misrepresented online, has been circulating in wellness spaces for years. At the pet store, it can cure your fish’s itchy fins. People have turned themselves permanently grey by consuming too much of it, a condition called argyria that is irreversible. The grey skin did not stop the trend. It just gave it a cautionary footnote. This is the cycle of misinformation: A substance with a legitimate but narrow and specific medical application is discovered by the wellness ecosystem. A study, usually conducted in a very different context than everyday human supplementation, is cited selectively. Influencers with large followings adopt it, photograph themselves consuming it, and list claimed benefits that range from plausible to fictional. The product becomes commercially available through supplement companies that are not required to prove their claims before selling. Doctors issue warnings. The warnings are dismissed as the establishment protecting its own interests. The cycle continues. Sadly, the methylene blue trend is not an anomaly. It is the algorithm working exactly as designed, surfacing content that generates engagement, regardless of whether that content is true, safe, or produced by anyone with the faintest qualification to make the claims they are making. Dave Asprey If you have already bought methylene blue because a fitness influencer told you it would fix your mitochondria, the most useful thing to do is speak to a pharmacist before consuming it, particularly if you are on any medication. The interaction risks are real, and the dosing information on supplement websites is not equivalent to medical guidance. If you are considering buying it because RFK Jr was photographed with it on a plane, it is worth noting that RFK Jr has also promoted a number of other health positions that place him outside the mainstream of medical consensus, and that a photograph of someone consuming something is not a clinical trial. And when people like Mel Gibson and Joe Rogan claim that the government is hiding the fountain of youth from you in the form of a magic blue drop, maybe it is time to reassess. nickelodeon And if you are an influencer with hundreds of thousands of followers who has been posting blue tongue selfies and listing the neurological benefits of a fish tank disinfectant, the UChicago researchers have a suggestion: the most effective way to improve health information on social media is for non-medical content creators to either stop making medical claims or to be significantly more transparent about the limits of their expertise. This is not a complicated ask. It is simply the difference between saying "I take this and I like it" and "this will protect your brain from Alzheimer's." One of those sentences is an opinion. The other is a medical claim. Your goldfish cannot tell the difference, and your audience deserves better than that.
