Rosemary has been used as a circulatory stimulant since antiquity, and that is precisely the property that makes it useful here. Cold feet are usually a circulation story — blood is not reaching the extremities in the volume it should — and rosemary encourages flow toward the surface of the skin.
Alongside that it carries real antifungal strength, which pairs neatly with the fact that cold, poorly circulated feet are also the feet most prone to fungal trouble.
The scent is bracing rather than relaxing. This is a morning oil, not a bedtime one.
