Episode 94: Medical marijuana

Episode 94: Medical marijuana

Author: Tom Chivers and Stuart Ritchie February 3, 2026 Duration: 1:02:58

Here’s another episode that revists a topic we’ve covered before. A while back, we did an episode on the downsides of cannabis (for example, the risk of psychosis). But of course, a lot of people claim there are medical benefits, too! Not least among them is Donald Trump, who recently re-scheduled cannabis so that it can be studied more for medical purposes.

That research is sorely needed. In this episode, we discuss the very uncertain state of our knowledge on medical marijuana.

The Science Fictions podcast is brought to you by Works in Progress magazine, where you can find Samuel Hughes’s excellent new article on “Urban expansion in the age of liberalism”, as discussed in today’s episode. That’s at worksinprogress.co—which is packed full of other great articles on science, tech, and human progress.

Show notes

* “Trump expands access to cannabis” (December 2025)

* Info from the DEA on drug schedules

* The new JAMA review on medical marijuana

* Reason article on the 2011 RAND study; Retraction Watch article on the same

* Studies on the crime impacts of medical marijuana (increase; neutral; decrease)

* Useful 2021 review of the wider societal effects of medical marijuana legalisation

* 2020 Arizona “natural experiment” study

* Washington Post article on the poor resemblance of “real” marijuana compared to what’s allowed for research studies

* Survey on the use of cannabis for medical purposes

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: 50

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