|Caption reads: Bridget McGann for Zenparenting.us and Iamnotthebabysitter.com|
So a recent op-ed piece in the New York Times that I will not link ("the op-ed that shall not be named") poo-poo'ed the veracity of the existing body of literature that supports the assertion of breastfeeding as beneficial to child nutrition and development. The author chose to bestow favor upon a select few secondary data analyses that showed no significant benefit.
Measurement sensitivity aside (because the degree to which a dose-response relationship can be measured with a 'yes/no' survey item is obviously very limited), I think it's important to remember that a BODY of literature has been steadily building for the last 30+ years. I've also seen another disingenuous headline that suggested there was a "growing body of evidence" that there is no substantial benefit to breastfeeding...just, no.
Biological Norm and Research Methods
First of all, let's remember that there is no benefit to breastfeeding. Breastfeeding is the biological norm. That means that in reality, the health outcomes associated with breastfeeding are the bar to which health outcomes associated with artificial baby milk should be measured. Thus the concept of risk-based messaging - as in, "the risks of artificial baby milk." But human beings are a bunch of tender, sensitive creatures, and research has shown that people don't like risk-based messaging. So we stick with "benefits of breastfeeding" knowing that this is a sort of disingenuous way to approach the messaging related to breastfeeding research/education/promotion. I hate to sound like a teenager, but whatever. If people don't like the feels from reading about risk, I have no issue seasoning and presenting the information in such a manner that it is more palatable to the consumer. As a parent I know that sometimes you have to make a silk purse out of a sow's ear, as the saying goes. This is just part of being human, communicating, and somehow getting through the layers of filters that we all have.
That being said, research, ya'll. There is a protocol, there is such a thing as rigorous methodology, meticulous study design and instrument development, and inherent limitations in the exploration of certain topics.
The gold standard of research design in health research is the randomized, controlled clinical trial. It would be unethical to randomly assign mothers and babies to either artificial baby milk or breastfeeding. So how do we address these limitations?
How's about a systematic literature review and/or a meta-analysis? These are two different approaches to pooling research results to try to achieve some kind of consensus. We have tons of independent, primary research studies floating around. The researchers who conduct systematic reviews attempt to collect, codify, appraise, and summarize existing literature on a specific topic (ie, breastfeeding and IQ). Meta-analysis involves the combining of existing data that was collected for various other primary studies to produce a single estimate (eg, treatment effect, or risk factors that contribute to morbidity).
A recently peer-reviewed manuscript that has been accepted for publication in Acta Paediatrica (but at the time of this writing has not yet gone through copyediting, typesetting, pagination or proofreading), has concluded that breastfed babies achieved a higher IQ by 3.44 points, on average (95% confidence interval: 2.3-4.6), compared to infants who were not breastfed. The systematic review sample included 17 studies. The mean difference in IQ was smaller when the researchers controlled for maternal IQ (mean difference 2.6, 95% confidence interval: 1.3-4.0).
Remember that these estimates are likely to be an underestimate of the true effects because of the framework from which the research question is approached, when you consider that breastfeeding is the biological norm, and the practice of breastfeeding was until recently somewhat of a lost art. We are still regaining our footing in that regard, make no mistake. There were many things lost to us when artificial baby milk became the norm in Western society, and I would venture to guess that much of the difficulty mothers encounter in their breastfeeding journey nowadays is related to the loss of that built-in breastfeeding culture that would inherently have passed much knowledge on through observation and modeling rather than overt instruction.
Let's #keepitmoving15, to borrow a hashtag from ROSE. We've come a long way, babes, but we still have a long way to go.