breast milk. These antibodies are active in the gut, stimulating development of the young digestive tract, and bestowing protection from infection. First milk (colostrum) contains three times the concentration of sodium found in mature breast milk. For this reason, your healthy, full-term baby does not require extra fluids during those first days. This means that the colostrum already being produced is usually sufficient. Colostrum also stimulates bowel actions, meconium is excreted more quickly, and the danger of jaundice is reduced.