For babies, breastfeeding is still best, even if it doesn't make them smarter (though it might)

"In a commentary that accompanies the study, Dr. Lydia Furman of Rainbow Babies and Children’s Hospital suggested that this won’t be the last word on breastfeeding and brain growth. On the one hand, the preponderance of studies shows that there’s “a small but durable impact of breastfeeding on intelligence.” On the other hand, the more that researchers are able to account for factors like a mother’s IQ and the exact duration of nursing, the weaker the relationship between nursing and intelligence is likely to get."