Mettre son grain de sel

Imagine you’re cooking soup with friends. Everyone’s happy: the broth smells good, the vegetables are tender. Then suddenly, someone walks in and sprinkles a random pinch of salt into the pot.  Everyone looks horrified:  “Who asked you??”

That’s exactly mettre son grain de sel: barging in with your little “improvement,” whether people wanted it or not.  Literally the expression means “to put in one’s grain of salt.”  Figuratively, it's most often used to mean adding one’s opinion when it was unasked-for.

It’s very close to the English “to put in one’s two cents,”  except the French version is culinary. Instead of tossing money, the French toss salt into everything.

Origin

The expression appeared in the 16th century in the form “mettre son sel” (“to put in one’s salt”).  At that time, salt was a precious commodity, sometimes even rare and heavily taxed. It was used both to preserve and season dishes.

Thus, “mettre son sel” meant adding something personal to enhance a matter, a story, or a conversation - just as one would season a dish.  Over time, the phrase evolved into “mettre son grain de sel” (“to put in one’s grain of salt”), emphasizing the idea of a tiny quantity: just a small pinch, but enough to change the flavor.  By the 17th–18th centuries, it had taken on the figurative meaning: to slip in an unsolicited remark or opinion, not always necessary, sometimes even annoying. Like over-salting a dish.

Examples

Elle ne peut pas s’empêcher de mettre son grain de sel dans toutes les réunions.
She can’t help but put in her two cents at every meeting.