Exactly 38 years ago Thursday, Whole Foods Market, the grocery chain Amazon would later go on to buy for $13.7 billion, was born.

It all started on a vegetarian co-op in Austin

The first Whole Foods Market store

Whole Foods' original founder and former co-CEO John Mackey, now 65, grew up eating cocoa puffs for breakfast, a hamburger for lunch and boxed macaroni and cheese for dinner, he tells host Guy Raz on the NPR show, "How I Built This." He didn't start to understand that there was a value in eating a vegetable-based, healthy diet until he moved into a vegetarian co-op, when he was 23, which, at the time, he thought of as an adventure.