Episode 27: Everything You Know About Expiration Dates is Wrong.

There's a version of this story where Al Capone gets credit for inventing the expiration date, worried about spoiled milk after a relative got sick. It's a great story. Most of it isn't true. What actually happened is stranger: for almost everything you buy at the grocery store, the date on the package isn't required by any law, isn't checked by any inspector, and in the case of "sell by," wasn't even written for you. It was a note from the manufacturer to the store clerk about when to pull stock off the shelf, and it ended up printed where shoppers could see it almost by accident.

This episode traces how we ended up with a fridge full of dates that don't mean what we think they mean: the dairy company that pioneered stamping freshness dates on milk cartons, the shoppers in the 1960s and 70s who cracked the industry's secret shelf codes by hand, the consumer advocate who took a job inside a grocery chain to push for dates people could actually read, and the 1975 government study that quietly found none of it reliably tracks whether food has actually gone bad. Along the way: how much money this confusion costs the average household every year, the one legal exception where a date really does matter, and the time I found all of this out the hard way, live, on this very show.