Doctor and journalist Chris van Tulleken wanted to know how ultra-processed foods affect us, so for a month he ate almost nothing but UPFs. His book Ultra-Processed People examines how the food we eat today is dramatically changing our bodies and minds.

This episode was produced by Siona Peterous, edited by Matt Collette, fact-checked by Isabel Angell, engineered by Patrick Boyd, and hosted by Noel King.

Transcript at vox.com/todayexplained

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