Does Breastfeeding Raise IQ?

If you ask a nursing mother why she chooses to nurse, you're likely to hear "because it's good for my baby." Among the other benefits, there is already a known link between a child having a slightly higher IQ and being breastfed. In a recent press release, researchers announced that they have determined that this is related to a particular gene that the baby has.

Researchers at King's College4 in London found a link between the gene that is responsible for this increase and breastfeeding. They were able to determine that the gene, FADS2, helps in the conversion of dietary fatty acids.

This study was conducted before these fatty acids were added to infant formula. Researchers believe that it is important for the psychiatric community to understand that our genes likely have a role in both intelligence and depression. They acknowledge that intelligence is based upon a combination of both nurture and nature, and not either of these exclusive of the other.

Dietary fatty acids are converted into the polyunsaturated fatty acids AA (arachidonic acid) and DHA (docosahexaenoic acid). During the first months after an infant is born, these two polyunsaturated fatty acids accumulate in an infant's brain.

Over 90 percent of the children involved in the study had a particular type of the FADS2 gene. When the infants had a copy of the "C" version of this gene and were breast-fed, they obtained a higher IQ.

Children who had the "G" version of the FADS2 gene did not show either a disadvantage or advantage in their IQ when breast-fed.

While many infant formula makers began adding both the DHA and AA fatty acids to their formulas, researchers have said that whether or not DHA and AA in formula remains to be seen.

There have been studies where primates and rodents were fed formula that contained both DHA and AA. The animals involved in these studies have shown enhanced intellectual abilities, and have had increased concentrations of DHA in their brains.

"Our findings support the idea that the nutritional content of breast milk accounts for the differences seen in human IQ. But it's not a simple all-or-none connection: it depends to some extent on the genetic makeup of each infant," said Terrie Moffitt, a professor of psychological and brain sciences in Duke University's Institute for Genome Sciences and Policy.

These findings were based upon the results of an intensive research study that involved over 3,000 children in both New Zealand and Britain.

Source:
http://www.dukenews.duke.edu/2007/11/breastIQ.html