When I was ten my family was at a hog roast at my uncle's and aunt's house. The Cajuns call it a couchon de lait (pronounced KO shawn de LAY). Couchon de lait means "pig with milk." What the Cajuns mean when they say that is, "milk fed pig." Maybe in the past someone actually raised a pig on milk and cooked it. But I think the term refers to the fact that a properly roasted pig is succulent.
Anyway, we were having a couchon de lait and the pig was taking much longer than the kids thought it should. The kids were starving, as kids usually are when they can smell the food cooking on a slow grill. My much older cousin, Juggie (a nickname that he was unaware that everyone in the family called him), said, "I don't care if it's done or not, I'm going to eat some."
So all the kids took up Jug's battle cry. We'd eat some even if it was not fully done. Mom told me, "You can't eat rare pork. You'll get beriberi (pronounced berry berry).
So over the years, if someone mentioned eating rare meat, I would either think or say, "Careful, you might get beriberi."
I was around twenty years old at my parents' table with my fiancee (now my wife) eating pork tenderloin. Someone said the pork was perfectly done. I said, "No chance of beriberi."
My mom gave me a skeptical look and said, "What?"
I said, "You can get beriberi from eating undercooked pork."
Mom said, "Where in the world did you hear that?"
I said, "You told me! Back at the couchon de lait at your sister's house. The kids wanted to eat the pig before it was done, and you told me I'd get beriberi."
Mom hooted. When she recovered her breath she said, "You can't get beriberi from undercooked pork! Beriberi is a vitamin deficiency!" Then she hooted some more.
Mom died in March of 2006.