Expired salt can be used to soak feet. If iodized salt is placed after the expiration date, oxidative decomposition may occur, especially the iodine content will be reduced. However, the sodium chloride component of the salt is relatively stable, and foot soaking has no special effect on the body. In family life, sometimes it is inevitable that salt is not used in a timely manner, may be due to the time is too long, the other trace components in the salt oxidative decomposition, the composition of the lower, usually not recommended for consumption, but the salt of the main component of sodium chloride is more stable in nature, such as the need to soak your feet. Foot soaking itself has more benefits, such as soothing joint pain, relaxing muscles, improving sleep quality, promoting blood circulation, etc. If necessary, you can use diluted salt water to soak your feet.