Multi‑site default study lessons

This episode, I spoke with Seth Ariel Green, a research scientist at the Humane and Sustainable Food Lab at Stanford university. He recently published a meta-analysis called “Meaningfully reducing consumption of meat and animal products is an unsolved problem” (EA Forum summary here) where he reviewed over 30 papers and hundreds of interventions on the topic. Seth also writes about the science of meat reduction on his Substack, called Regression to the Meat, which I highly recommend checking out for some accessible and fun to read writing about meat reduction.

We talk about why Seth is more sceptical than most about plant-based defaults, what actually works when it comes to changing people’s food choices, why some research in this space is misleading and new interventions to shape diets and food choices that he is excited about. 

Chapters:

(00:00:00) Cold intro

(00:00:53) Introduction to Seth and his work

(00:05:38) What are defaults and why is Seth sceptical

(00:19:55) The best paper on defaults - what does it mean for advocates?

(00:28:50) What does the research on meat reduction say?

(00:34:25) Is 5 percentage points a small or big change in meat consumption?

(00:43:20) What actually works in reducing meat consumption?

(00:50:18) Potential interventions that Seth is excited about

Resources:

• Seth's blog 
• Wayne Hsiung’s New Yorker interview
• Ginn, J., & Sparkman, G. (2024). Can you default to vegan? Plant-based defaults to change dining practices on college campuses.
• Finkelstein et al (2012). The Oregon health insurance experiment: evidence from the first year. 
• Jalil, A. J., Tasoff, J., & Bustamante, A. V. (2023). Low-cost climate-change informational intervention reduces meat consumption among students for 3 years
• Hope, J. E., Green, S. A., Peacock, J. R., & Mathur, M. (2025). Taking a bite out of meat, or just giving fresh veggies the boot? Plant-based meats did not reduce meat purchasing in a randomized controlled menu intervention
• Edwards, D. M., Ondish, P., & Neff, R. (2025). Increasing meatless options to decrease meat consumption
• Kramer, L. A., & Landry, P. (2025). How the Sausage Is Made: Testing the Effectiveness of an Informative Video in Promoting Sustainable Food Consumption. 
• Kenny Torella’s Is it even possible to convince people to stop eating meat?
• Warren belasco: food, the key concepts 
• Join our lab’s seminar email list! 

With thanks to Tom Felbar (Ambedo Media) for amazing video and audio editing!

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