Breastfeeding is the feeding of an infant or young child with milk from a woman's breasts. Babies have a sucking reflex that enables them to suck and swallow milk.With few exceptions, human breast milk is the best source of nourishment for human infants. However, experts disagree about how long to breastfeed to gain the greatest benefit, and how much more risk is involved in using artificial formulas.A mother may breastfeed her infant, or another infant, e.g., as a wet nurse. While there are conflicting studies about the relative value of artificial feeding, including infant formula, it is acknowledged to be inferior to breastfeeding for both full term and premature infants. In many countries, including developed countries, artificial feeding is associated with more deaths from diarrhoea in infants.National governments and international organizations promote breastfeeding as the best method of feeding infants in their first two years and beyond. The World Health Organization (WHO) and the American Academy of Pediatrics (AAP) also promote breastfeeding. Regulating authorities recognize the superiority of breastfeeding but also try to make artificial feeding safer.