Since becoming a mom, and especially since starting this blog, I have paid particular attention to new breastfeeding research. After all, my training is in nutrition, and breast milk is one of the most interesting foods around. Plus, I’m currently lactating and still breastfeeding my daughter a few times per day, so it’s on my mind.
When I look back at the papers that I have covered and those that I find on other blogs and media outlets, I notice that many focus on how breastfeeding improves outcomes in babies.
But I also notice that when I blog about breastfeeding research, I have to spend a big chunk of the piece talking about the limitations of the study. Breastfeeding research – at least when conducted in humans – will always have big limitations that require disclaiming and explaining. The problem is that it is impossible to randomize breastfeeding trials or to “blind” the subjects to feeding type. It is difficult to know, despite the fanciest statistical methods, if it is breast milk that makes those babies thinner, smarter, stronger, cry more, etc, or if there are other factors at play in this complex thing called human life. Sometimes, by the time I’ve listed the problems with interpreting a breastfeeding study, I wonder if these findings were actually meaningful, and I’m sure my readers feel the same way.
Elsewhere around the Internet (not so much on my blog), I often see comments to this effect on articles about the latest research on the benefits of breastfeeding:
“Another useless study. Obviously we mammals were meant to feed our babies breast milk. I don’t know why scientists waste their time and our money with this stuff.”
Why bother doing more research on outcomes associated with breastfeeding? It is pretty clear that breastfeeding is a great way to feed an infant. Maybe it is time to stop oohing and awing over breast milk.
There is something to this. I think we see a lot of papers published that report on the benefits of breast milk just because this is a hot topic now. These data are often pulled from a larger epidemiological data set. A positive association is found between breastfeeding and some good outcome, and the authors throw it together to make a separate paper. It is accepted for publication in part because breastfeeding promotion is a public health priority now. I’d be willing to bet that there are lots of researchers out there that have checked for an association between breastfeeding and an outcome in their data set, found none (or even a negative one they can’t explain), and not bothered to write up a paper or had their paper rejected because a non-association is just not that exciting.
Still, I do think that these observational studies can have some value. One that I wrote about a couple of weeks ago found an association between exclusive bottle-feeding, whether formula or expressed breast milk, and increased weight gain in infants. There were LOTS of limitations to this study. However, I thought that the data raised an interesting question: Can we modify the way we bottle-feed babies such that growth in bottle and breastfed babies starts to look more similar? At the very least, it is something for us to think about, and it could also inspire a hypothesis for a future study, one that could ultimately improve the way we feed babies. Regardless, not all papers can be groundbreaking. Most add to a body of evidence over time. Some are flukes, which we realize when they can’t be replicated. But all ideas have to start somewhere, and in science, they start with observation. The problem is not as much in the research (scientists are usually all too willing to point out the limitations of their work) as it is in the media’s spin of stories to make them seem urgently relevant to the parenting public.
Of course, the really important lactation research is probably happening in laboratories – in petri dishes and in lab animals, not within an epidemiological data set. These studies, the ones that are slowly starting to illuminate what it is about breast milk that makes it so good for babies, may not catch the eyes of bloggers and journalists because the paper titles contain words that we don’t understand or the outcomes are more subtle: a small change in cell growth or difference in oligosaccharide composition. It is harder to explain and write about, and we often assume that it will feel less relevant to a reader. I’m guilty of this attitude as well, but I’m trying to change my ways.
Recently, Fearless Formula Feeder posed this question to her readers, many of which are women who have struggled with breastfeeding: what type of breastfeeding research would you like to see? The truth is that if you’re breastfeeding and having a good experience with it, you probably love to see these reports on the benefits of breastfeeding. But if you’re feeding formula – for whatever reason and no matter how fearlessly – you undoubtedly get tired of these stories, particularly when the studies have the limitations I discussed above. Reading FFF’s post, it occurred to me that moms like these are also the most likely to benefit from new breastfeeding research. After all, a better understanding of breast milk will pave the way for better formula. A better understanding of the etiology and risk factors for problems with breastfeeding will pave the way for targeted, specific support for moms who want to breastfeed but struggle to do so. And in fact, the FFF’s came up with some really great research questions in the comment thread on that post. Are scientists working on their questions, and we just aren’t hearing about it?
One of the major sources of funding for breastfeeding research in this country is the National Institutes of Health. These are taxpayer dollars. Did you know that there is an open-access database where you and I and anyone with access to the Internet can learn how our tax dollars are being spent to support research?
If you’re curious, do a search for any health-related topic, and you can learn what NIH-funded researchers are working on today. If a particular grant interests you, you can do a Pubmed search for the Principal Investigator (PI) to see what they’ve published on that topic in the past, and you can expect to see papers coming from the current grant in the next couple of years.
I did a few quick searches for “breastfeeding” and “infant formula,” and I found some really cool studies in the works:
Clinical Epidemiologic and Biologic Studies of Donor Human Milk and Breastfeeding, Tarah T. Colaizy, University of Iowa
Prevention of Overfeeding During Infancy, Kathryn G. Dewey, University of California, Davis (This grant speaks directly to some of the questions that came out of that bottle-feeding and weight gain study I mentioned earlier.)
Mechanisms by which Human Milk Oligosaccharides Protect Against Rotavirus, Sharon M. Donovan, University of Illinois
Structure, Functions, and Genetic Diversity of Oligosaccharides in Milk, Carlito B. Lebrilla, University of California, Davis
Establishing the Vitamin D Requirements During Lactation, Bruce W. Hollis, Medical University of South Carolina
Estrogenicity of Soy Formula, Walter Rogan, National Institute of Environmental Health Sciences (This grant is targeting many of the questions FFF raised in her post on the recent study comparing development in babies fed soy formula, cow’s milk formula, or breast milk.)
Boosting Breastfeeding in Low-Income, Multiethnic Women: A Primary-Care Based RCT, Karen A. Bonuck, Albert Einstein College of Medicine
Mediating Factors in the Relationship Between Obesity and Poor Lactation Outcomes, Laurie A. Nommsen-Rivers, Children’s Hospital Medical Center, Cincinnatti
I can’t wait to read the papers that come out of these grants, even though I know they’ll all have limitations and create more questions. That’s science for you. But seeing many of the questions that I’ve wondered about myself articulated by scientists and dollars allocated towards answering them gives me renewed enthusiasm for the value of science to humanity and to my life.
What questions do you hope scientists are working on today?