It is true that drinking formula or juice while lying down can increase the risk of ear infections. This is because the liquid can enter the eustacian tube and introduce bacteria or viruses into the middle ear. The many germ-fighting ingredients in human milk keep harmful bacteria from bothering baby, so that stuffed-up noses and ears are less likely to become infected middle ears. Because breastfed babies are fed in a more upright position, they're less likely to experience milk backing up through the eustachian tube into their ears; if this does happen during a breastfeeding session, human milk is less irritating to the tissues of the middle ear than infant formula. Breastfed babies have fewer, or at least less severe, colds than formula-fed babies. Fewer colds means fewer ear infections. Breastfed babies have fewer respiratory allergies, another cause of fluid building up in the middle ear, which setts the stage for bacteria to grow.