The idiom "To take something with a pinch of salt" means "To treat something with scepticism." This phrase advises caution and a degree of doubt when presented with information, especially if it seems exaggerated, unlikely, or unverified. It suggests that one should not believe something entirely or immediately, but rather consider it with a critical and questioning attitude.
The origin of the idiom is thought to come from the idea that food is easier to swallow with a pinch of salt, metaphorically suggesting that difficult or dubious information is easier to accept if one is prepared to doubt it. For example, "You should take his promises with a pinch of salt; he rarely follows through." It implies a need for discernment and a healthy dose of disbelief. It does not mean to accept something immediately, exaggerate a statement, or refuse to listen, but rather to listen critically.