In general, only breastmilk or formula should be used if your baby is less than six months old.

Between six and twelve months, supplementing with solids (instead of formula) or very small amounts of cow, goat, soy or rice milk is less of a problem, as long as baby is still nursing for the majority of milk intake and baby is not allergic. However, babies under a year are more at risk for allergic reactions (see below) so it can be a good idea to wait.