Spill the beans/the soup/one’s guts

All these expressions are metaphors for divulging or confessing all and, curiously, are all Americanisms that date from the early 20th century. There is no special significance attached to beans or soup that, in not spilling them, one could be said to be keeping secrets. Guts, on the other hand, are a very different matter. Spilling them conjures up somewhat revolting imagery, which some bright spark thought would make a good metaphor for confessing all. Perhaps the drawing of guts in hanged, drawn and quartered was the inspiration, the mere thought of which would make most people confess all. Several sources, including Merriam-Webster, maintain that spill on its own, without beans, soup, or guts, means to divulge or confess all. This meaning, moreover, dates from as far back as the late 16th century. So quite why things like beans, soup and guts were added to the equation some 400 years later is not entirely clear.