It is generally recommended that babies start to take salt supplements in small amounts after 13 months of age and in moderation after three years of age. The digestive and renal systems of babies before 13 months of age are relatively delicate and not yet fully developed. Early intake of salt will affect the normal development of the kidneys or digestive system, and early intake of sodium will affect the normal absorption of other elements, such as calcium, which will cause a series of adverse reactions. In addition, babies before the age of 13 months through breast milk or other complementary foods can already provide a sufficient amount of sodium and other elements, so it is generally recommended that after the age of one year to start a small amount of salt supplementation, the best daily intake of not more than 1.5 grams; and must be gradual and orderly, generally to the age of three years after the gradual transition to the normal intake of salt.