There are a couple references here, 2008 being the most recent (PDF): http://www.brainrules.net/pdf/brain-rules-for-baby-references-smart-baby-soil.pdf http://w

There are a couple references here, 2008 being the most recent (PDF): http://www.brainrules.net/pdf/brain-rules-for-baby-references-smart-baby-soil.pdf http://www.brainrules.net/pdf/brain-rules-for-baby-reference... The author of the book "Brain Rules for Baby" is on the side that breastfeeding leads to smarter babies (~5 IQ points?), and claims that the principles in the book are backed up by peer-reviewed research. As for the mechanism behind it, not sure this is known. I've heard speculation that it is the antibodies, and that breastfed kids have a little extra learning time since they aren't distracted with as many illnesses. But I've also heard that receptors on the mother's breasts react to the babies saliva, resulting in milk nutrient profile slightly customized to the baby's current needs (so, would donated milk not have the same effect?).