The Medical Research Council team said that although it appears that formula-fed babies are more contented, babies still need breast milk for a variety of reasons.
In their study, the MRC scientists asked 300 mothers to comment on their baby's temperament and the feed given to the baby. Of the 300 babies, 137 were exclusively breastfed, 88 were exclusively bottle-fed, and 91 received a mixture of formula and breast milk. It emerged that breastfed babies tended to cry more and had challenging temperaments.
"Bottle-fed babies may appear more content, but research suggests that these infants may be overnourished and gain weight too quickly," said lead researcher Dr Ken Ong. "Our findings are essentially similar to other stages of life; people often find that eating is comforting."