I want to keep this article as a short post, so read the BBC article for the details. But, I would like to give kudos to the BBC writer of this article – he or she has gotten this one mostly right. But there are a number of issues that he or she has missed in the original paper. The biggest problem that I have is that it is not clear from this study, how long the children were breastfed. The study groups are two large groups from New Zealand and Britain in which parents were surveyed when the kids were age two to three as to whether they were breastfed or not. However, there is no indication as to how long the children were breastfed. A second issue that I have is that it is true that in the groups that were studied, the allele of the FADS2 gene that is responsive to breast milk is present in 90% of those tested. However, these groups are almost exclusively of western European ancestry. In the New Zealand study, aboriginal people are even eliminated from the study to avoid potential problems (this is buried in Materials and Methods). There is no indication of how common this allele is outside the British Isles. Third, the scientists have eliminated any variation due to social class, the intelligence of the mother and differences in birth weight. However, variation due to the fathers’ intelligence is not eliminated. Finally, these two groups were studied in the early 70’s and mid-90’s respectively – prior to supplementation of formula with some of the fatty acids that are thought to be important to the IQ boost. Most formulas now include these components.

All that being said, I think that their conclusions are generally valid and breastfeeding certainly is not going to hurt. Personally, I do not have strong feelings about breastfeeding. Sinead is breastfeeding Zach and we’ve got our own personal reasons for making that choice. The current social climate in Britain is a little bit heavy-handed about breastfeeding. So much so that in some cases women may be made to feel as if they’re hurting their children by bottle feeding. I think that this kind of evangelism about breast feeding can be a bit much, particularly if you can not breast feed for whatever reason. It’s important to remember that this as with any scientific study does not prove anything, it only provides more data to support a hypothesis. As the authors of the PNAS study say themselves, “although evidence [for this hypothesis] is mounting, it has not yet been proven.”

Image Credits:

Breastfeeding photo