Infants who take water in addition to breast milk or formula food may be at a serious health risk, say Paula Scariatt and her colleagues at the Center for Disease Control and Prevention, Atlanta, USA. Such infants are likely to develop altered mental state, abnormally low body temperature, bloating and seizures. The problems start when necessary sodium in the blood is diluted too much. Babies less than a month old are especially at the risk as they cannot filter water from their systems as fast as older infants do. According to the American Academy of Paediatrics, except in hot weather, human milk or formula food provides infants enough water ( Archives of Paediatrics and Adolescent Medicine , Vol 151, No 8).