Breast-fed children are more intelligent than their bottle-fed counterparts, but this has nothing to do with the content of the milk they receive, a study published in the British Medical Journal said... Researchers... found that mothers who breast-feed tend to be more intelligent... "When this fact was taken into account, most of the relationship between breast-feeding and the child's intelligence disappeared,"... "This research shows that intelligence is determined by factors other than breast-feeding,"... The researchers found that children who were breast-fed did better on IQ tests, but this was because their mothers were more intelligent, better educated and able to provide a more stimulating home environment. Part of the research methodology included testing pairs of siblings, for whom feeding habits differed. "Comparing two people from the same family like this is a good way of getting results that are less affected by family background. This confirmed the earlier results -- the breast-fed child was no more intelligent."