In Western superstition, what action is traditionally believed to prevent bad luck after spilling salt?

In Western superstition, throwing spilled salt over the left shoulder is traditionally believed to prevent bad luck.

Salt was historically valuable for preserving food, seasoning meals, and supporting trade, so spilling it could be interpreted as wasteful or ominous. In Christian-influenced folklore, the left side was sometimes associated with the Devil, which helps explain why the corrective gesture is usually directed over the left shoulder.

The practice became widely recognizable through European and American custom, though versions differ. Some people pinch a small amount of the spilled salt and cast it backward without looking. The gesture is symbolic rather than a guaranteed remedy.

The superstition is often linked to Leonardo da Vinci’s painting The Last Supper because Judas is said to have knocked over salt in some interpretations. That connection is debated: the painting’s visible salt cellar is a detail, but it does not by itself establish the later ritual.