This episode on the pellagra epidemic focuses on its prevalence in the U.S. in the early 20th century. Some of the scientific work done to understand it involves self-experimentation, and some of it is ethically problematic by today’s standards.
Research:

Unearthed! In July 2026, Part 1
41:36

SYMHC Classics: Raincoats
39:10

Behind the Scenes Minis: Shoes, Shoes, Shoes!
30:14