ScienceDaily (Oct. 27, 2010) — Ask someone in the know to list the substances in breast milk that make it the ideal food for newborns and you may hear about proteins that guard against infection, fats that aid in the development of the nervous system and carbohydrates that promote the growth of healthy bacteria. But, you may not hear too much about the nitrite and nitrate in breast milk and their contributions to developing gastrointestinal, immune and cardiovascular systems.