There is some data to suggest there may be a link.
However. The data is very limited. Mt sinai did a meta of 46 studies and found a link (not necessarily causal). A Swedish population study of like 2.5 million children found no link. Etc.
The modest increase that could exist is unclear and confounded. Is it Tylenol or is something that the Tylenol is being taken for? Eg if the mom is having frequent headaches or fevers is the underlying condition impacting development and making it look like Tylenol does?
But why?
Two big answers:
Kenvue (Tylenol manufacturer) is not exactly a “pharmaceutical giant”. They’re a much easier target for rfk to go after with much less in terms of resources. They absolutely will sue though and appear to be preparing to do so though. But going after vaccines (his big target), especially stuff like Covid vaccines, means going after real pharmaceutical giants. Moderna, Pfizer, Johnson and Johnson, etc. deeeeeep pockets and serious legal teams. This may be a fight he feels he can “win” to start gaining momentum and precedent.
IMO the bigger reason is political capital. He has a large following of desperate parents that want an answer for why their child has autism or intellectual disability. I know a lot of people on here are like “autism is a superpower” and that’s great but these people are stuck in the disability mindset. It’s also important to remember that autism is a broad spectrum. Some of these parents have children that are nonverbal, that can’t toilet or shower independently, that get extremely violent when frustrated, that need 24/7 assistance and will never live independently. Of course some of them are just frustrated that their otherwise fine kid isn’t “normal” enough but that’s a whole other frustrating thing.
They’re desperate for answers. The reality of the situation is that there isn’t a simple answer. The overwhelming evidence suggests a combination of factors: genetics, environmental, social and behavioral. But this is unsatisfying. I’ve worked with people on this for years and when you say “it’s probably a combination of factors” they are never happy with that. They want something to blame. This is the political capital. He is giving them that. Basically everyone has taken Tylenol within the past year. Most pregnant women will take Tylenol at some point for discomfort, pain, fever, etc.
Now they will not only have the answer to “what did this”, they will have him as a person to hold up as the savior who gave them the answer. I saw the same thing happen when I started around 2010. Even though it was years after it happened people still attached to Wakefield and were so grateful he gave them the explanation that it was the MMR vaccine. They’d “protect their other children” as a result by not vaccinating them. Didn’t matter if you pointed out Wakefields proven financial links to an alternative MMR vaccine, the retraction of the paper, him getting his medical license revoked, etc. That’s how desperate they are for answers. FWIW Wakefield is still super rich and got married to literal supermodels so that’s why he doubled down and probably a major factor in why rfk is doing the same
Given the overwhelming number of well structured studies showing no relationship, the meta analysis that potentially, may, if you quint and really try to bend the light to see it in a certain way, is simply too far away to have any meaningful value.
This is bad reasoning. For one the mt Sinai meta is not poorly structured. For two there’s not exactly an “overwhelming number” of contrary studies. For three there’s a number of studies besides the mt Sinai study. You dismiss the meta on lack of merit without actually examining it and place it against fantastical papers (that may or may not exist, and as mentioned the quantity of which is being exaggerated)
In addition to the mt Sinai paper 2 other similar papers came out in 2025 (one from Harvard, one from environmental health) showing a link. There’s also the danish birth study which showed a link between Tylenol and a specific presentation of autism (hyperkinetic symptoms, closer to adhd).
Papers to the contrary aren’t necessarily “overwhelming” either, there’s 3-4 metas recently that show no causal link and the big one is the Swedish birth study I referenced in the initial post. But that’s countered by the above metas and the danish birth study.
Therein lies the issue and why it’s a point of debate. RFK is wrong to do what he is doing because the data is not strong enough to make the bold claim that he is making. He is a charlatan and likely scamming somehow (perhaps to sell folinic acid, which also has spurious data for efficacy). However, on the same point to reject the potential of Tylenols impact entirely because RFK is interested in it as a potential causal factor is equally foolish. It could be a factor. We don’t know yet. It needs more exploration. This could increase funding to explore it potentially (which could be a total waste of time).
IMO you should probably listen to the mt Sinai paper, which recommends that you take Tylenol if necessary during pregnancy as “untreated maternal fever and pain pose risks such as neural tube defects and preterm birth” and ultimately recommends a balanced approach limiting Tylenol exposure, eg try not to take tons of it
Yes, I touched upon this towards the end of my (admittedly lengthy) post. Also, it’s not “their” meta. It’s a meta done by mt Sinai and Harvard (eg done with rigor) which openly admits the link cannot be established as causal because, as stated, there are many confounding factors to consider
Yeah, acetaminophen is like the most common painkiller and fever reducer. They make syrup versions of it you can give to children. And, uh, suppositories for babies that are too small for the syrup.
I know youre just speaking for example but just so anyone reading knows if a baby is that small please call a doctor as you should not be treating them with otc meds. Fever or significant discomfort in the first two months is potentially a real big deal and should always be evaluated by a physician
Not only that. But the sheer number of kids who didn’t develop autism but had Tylenol (or the vaccines! Same shit different goat.)
Like, most kids in the US had Tylenol. Most kids don’t develop autism. Other things most kids are exposed to: going outside. Going inside. Having a pb&j. Wearing clothing. Eating ice cream. The incidence of going to McDonald’s for soft serve and being told the machine is broke.
It’s patently ridiculous, and even if there’s a correlation, it’s pretty clear something else is going on, and you don’t have to be a physician to see that.
There is some data to suggest there may be a link.
However. The data is very limited. Mt sinai did a meta of 46 studies and found a link (not necessarily causal). A Swedish population study of like 2.5 million children found no link. Etc.
The modest increase that could exist is unclear and confounded. Is it Tylenol or is something that the Tylenol is being taken for? Eg if the mom is having frequent headaches or fevers is the underlying condition impacting development and making it look like Tylenol does?
But why?
Two big answers:
Kenvue (Tylenol manufacturer) is not exactly a “pharmaceutical giant”. They’re a much easier target for rfk to go after with much less in terms of resources. They absolutely will sue though and appear to be preparing to do so though. But going after vaccines (his big target), especially stuff like Covid vaccines, means going after real pharmaceutical giants. Moderna, Pfizer, Johnson and Johnson, etc. deeeeeep pockets and serious legal teams. This may be a fight he feels he can “win” to start gaining momentum and precedent.
IMO the bigger reason is political capital. He has a large following of desperate parents that want an answer for why their child has autism or intellectual disability. I know a lot of people on here are like “autism is a superpower” and that’s great but these people are stuck in the disability mindset. It’s also important to remember that autism is a broad spectrum. Some of these parents have children that are nonverbal, that can’t toilet or shower independently, that get extremely violent when frustrated, that need 24/7 assistance and will never live independently. Of course some of them are just frustrated that their otherwise fine kid isn’t “normal” enough but that’s a whole other frustrating thing.
They’re desperate for answers. The reality of the situation is that there isn’t a simple answer. The overwhelming evidence suggests a combination of factors: genetics, environmental, social and behavioral. But this is unsatisfying. I’ve worked with people on this for years and when you say “it’s probably a combination of factors” they are never happy with that. They want something to blame. This is the political capital. He is giving them that. Basically everyone has taken Tylenol within the past year. Most pregnant women will take Tylenol at some point for discomfort, pain, fever, etc.
Now they will not only have the answer to “what did this”, they will have him as a person to hold up as the savior who gave them the answer. I saw the same thing happen when I started around 2010. Even though it was years after it happened people still attached to Wakefield and were so grateful he gave them the explanation that it was the MMR vaccine. They’d “protect their other children” as a result by not vaccinating them. Didn’t matter if you pointed out Wakefields proven financial links to an alternative MMR vaccine, the retraction of the paper, him getting his medical license revoked, etc. That’s how desperate they are for answers. FWIW Wakefield is still super rich and got married to literal supermodels so that’s why he doubled down and probably a major factor in why rfk is doing the same
Given the overwhelming number of well structured studies showing no relationship, the meta analysis that potentially, may, if you quint and really try to bend the light to see it in a certain way, is simply too far away to have any meaningful value.
This is bad reasoning. For one the mt Sinai meta is not poorly structured. For two there’s not exactly an “overwhelming number” of contrary studies. For three there’s a number of studies besides the mt Sinai study. You dismiss the meta on lack of merit without actually examining it and place it against fantastical papers (that may or may not exist, and as mentioned the quantity of which is being exaggerated)
In addition to the mt Sinai paper 2 other similar papers came out in 2025 (one from Harvard, one from environmental health) showing a link. There’s also the danish birth study which showed a link between Tylenol and a specific presentation of autism (hyperkinetic symptoms, closer to adhd).
Papers to the contrary aren’t necessarily “overwhelming” either, there’s 3-4 metas recently that show no causal link and the big one is the Swedish birth study I referenced in the initial post. But that’s countered by the above metas and the danish birth study.
Therein lies the issue and why it’s a point of debate. RFK is wrong to do what he is doing because the data is not strong enough to make the bold claim that he is making. He is a charlatan and likely scamming somehow (perhaps to sell folinic acid, which also has spurious data for efficacy). However, on the same point to reject the potential of Tylenols impact entirely because RFK is interested in it as a potential causal factor is equally foolish. It could be a factor. We don’t know yet. It needs more exploration. This could increase funding to explore it potentially (which could be a total waste of time).
IMO you should probably listen to the mt Sinai paper, which recommends that you take Tylenol if necessary during pregnancy as “untreated maternal fever and pain pose risks such as neural tube defects and preterm birth” and ultimately recommends a balanced approach limiting Tylenol exposure, eg try not to take tons of it
My job and my team are expertis in clinical evidence within the UK. If the ABPI recognise our views, I think we’re good enough here.
Do you have any idea how common it is to give people, even kids, Tylenol?
I’m not looking up their meta, but I suspect it’s as informative as the meta that shows a “link” between autism and vaccines.
Might as well investigate a link between Peanut butter and jelly sandwiches or wearing clothes.
Yes, I touched upon this towards the end of my (admittedly lengthy) post. Also, it’s not “their” meta. It’s a meta done by mt Sinai and Harvard (eg done with rigor) which openly admits the link cannot be established as causal because, as stated, there are many confounding factors to consider
Yeah, acetaminophen is like the most common painkiller and fever reducer. They make syrup versions of it you can give to children. And, uh, suppositories for babies that are too small for the syrup.
I know youre just speaking for example but just so anyone reading knows if a baby is that small please call a doctor as you should not be treating them with otc meds. Fever or significant discomfort in the first two months is potentially a real big deal and should always be evaluated by a physician
I always turn these around and ask given the study size, what is the confidence interval of the number of autism diagnoses attributable to Tylenol?
Often the number is surprisingly low given the other factors (and frequently uncontrolled confounders.)
Not only that. But the sheer number of kids who didn’t develop autism but had Tylenol (or the vaccines! Same shit different goat.)
Like, most kids in the US had Tylenol. Most kids don’t develop autism. Other things most kids are exposed to: going outside. Going inside. Having a pb&j. Wearing clothing. Eating ice cream. The incidence of going to McDonald’s for soft serve and being told the machine is broke.
It’s patently ridiculous, and even if there’s a correlation, it’s pretty clear something else is going on, and you don’t have to be a physician to see that.