Episode 87: Does Tylenol cause autism?

Episode 87: Does Tylenol cause autism?

Author: Tom Chivers and Stuart Ritchie October 14, 2025 Duration: 1:06:43

You requested; we delivered. Lots of Science Fictions listeners have asked us to take a look into Donald Trump and RFK, Jr.’s recent claims about Tylenol (that is, paracetamol or acetaminophen—all the same thing). Does it cause autism?

It turns out there’s more to this than you might’ve thought—regardless of all the recent hype, a lot of very reputable scientists take the idea seriously. But should they? In this emergency podcast, we go through all the relevant studies.

The Science Fictions podcast is brought to you by Works in Progress magazine. In the ad this week we mentioned “The Death Rays that Guard Life”, an article from Issue 20 of the magazine about far-UVC light and how—with a lot more research—it might be the next big thing for reducing the spread of germs in hospitals and classrooms. Find that and many other articles and podcasts at worksinprogress.co.

Show notes

* The FDA’s September 2025 announcement on Tylenol and autism

* The UK’s Department of Health and Social Care announcement the same day

* “The phrase ‘no evidence’ is a read flag for bad science communication”, by Scott Alexander

* 2003 theoretical paper with speculation about paracetamol and neurodevelopmental disorders

* 2013 sibling control study in the International Journal of Epidemiology

* “Ecological” study in Environmental Health from 2013 about circumcision rates, paracetamol, and autism

* 2015 Danish seven-year follow-up study

* 2019 cord blood study in JAMA Psychiatry

* 2021 “consensus statement” on paracetamol and neurodevelopment

* 2025 Japanese sibling-control study

* 2024 very large Swedish sibling-control study

* Study that sparked the current debate: the “Navigation Guide” review from Environmental Health

* Description of what “Navigation Guide” is

* STAT News on the evidence for a paracetamol-autism link; and on the controversy about the Dean of the Harvard School of Public Health

* White House statement defending the existence of the link

* BMJ article summing up the controversy

Credits

The Science Fictions podcast is produced by Julian Mayers at Yada Yada Productions.



This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit sciencefictionspod.substack.com/subscribe

Every week, Tom Chivers and Stuart Ritchie pull apart the biggest arguments and most confusing claims making headlines. Science Fictions isn't just about celebrating breakthroughs; it's a necessary dive into the messy, contested, and often surprising realities of how science actually works. You'll hear them unpack heated debates, examine questionable studies, and explore why even solid research can sometimes lead to public confusion. This podcast serves as a guide through the noise, separating compelling evidence from overblown narratives. Each episode feels like a conversation with two deeply informed friends who aren't afraid to ask tough questions, offering clarity on topics that matter. For anyone curious about the stories behind the science headlines, this is an essential listen. Tune in for thoughtful analysis that goes beyond the press release, grounded in a genuine fascination with how we know what we know.
Author: Language: English Episodes: 100

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