So, in this post I'm going to wade into a topic* against my better judgment and the advice of my husband.
I didn't want to write about this because 1) I know next to nothing about autism, and 2) sometimes if you say "don't worry" people respond by thinking, "What?!? There's something to worry about?!?" So you are hereby ordered to take a deep breath before reading the rest of this post.
Here's the issue: Recently there has been a lot of online discussion about breastfeeding and autism. This discussion was prompted by a two-year old article on the UCSF website, which discusses a rat study that suggests a link between high levels of PCBs in milk and neuro-developmental disorders like autism.
Here are the points I'd like to make:
1) Research to date suggests an inverse relationship between breastfeeding and autism. Let's get something straight before proceeding - I am not, not, not suggesting that formula feeding causes autism. Got that? I am going to present the findings of the very few studies that have looked at feeding method and autism incidence, so that you can clearly see that the research to date hasn't borne the idea of a causal link between breastfeeding and autism out at all. Here they are: This study, based on parent surveys, found an association between breastfeeding (and also DHA/ARA supplemented formula) and lowered risk of autism. This study on casomorphins found an inverse relationship between breastfeeding and a risk factor for psychomotor delays and other diseases such as autism. This older study on weaning and autism found an inverse relationship between breastfeeding and autism incidence. This analysis of three studies in which babies with higher levels of dioxin exposure through breastmilk than exist today were measured in terms of health and developmental outcomes. It found that breastfed babies had better mental development than formula fed babies.
2) Formula has PCBs and other pollutants, too. Sometimes I think that this issue gets framed in terms of "toxins or no toxins," but the truth is that your choice is between breastmilk which contains pollutants and formula which contains pollutants. Dr. Kathleen Arcaro, environmental toxicologist at the University of Massachusetts said in an interview for this blog that "pollutants are widely distributed [i.e. in the air, in water] and therefore are in cow’s milk and formula." Some pollutants, like PAH, are found in higher amounts in formula than in breastmilk. Viewed this way, why wouldn't you choose the food which delivers many other health and developmental advantages for both of you?
3) Levels of PCBs in breastmilk are going down. Dr. Arcaro noted in the same interview that "the good news is that the concentration of some lipophilic (fat-loving) environmental pollutants in breast milk is decreasing. For instance the level of many pesticides (DDT and its metabolites) and polychlorinated biphenyls (PCBs) has greatly decreased over the last 30 years." PDBE levels have increased, but some states have started to ban their use.
4) Rats are not humans. Enough said.
For more, check out these past posts on toxins and breastfeeding and formula.
We should all be concerned about toxins in breastmilk. And we should all be conerened about autism. But let's not jump to the conclusion that one causes the other.
*Many thanks to Heather, creator of Hathor the Cowgodess, who currently draws and blogs at mama-is.com, for the use of her drawing in this post. My podcast interview with her is my favorite one - check it out!
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