A study has popped up that allegedly provides ‘the first comprehensive picture of the health and economic benefits of breastfeeding,’ and suggests that 721 premature deaths of children in the United States, 2,619 deaths from mothers, and billions of healthcare dollars could be saved with optimal breastfeeding. While the numbers the researchers drummed up may imply this, their methods leave a great deal to be desired. In particular, it seems that two of the researchers, Melissa Bartick and Arnold Reinhold, have not learned their lesson from their earlier study.
In Brief: The 2010 Study
Six years ago, Bartick and Reinhold released a study that suggested $13 billion dollars in healthcare spending and 911 deaths, mostly in infants, could be saved if 90% of US families complied with medical recommendations for breastfeeding. They got these figures by applying odds ratios from a 2007 report to a collection of statistics they drew from various sources. This would merely be weird and questionable except for one major problem: the report they got their odds ratios from could not find a clear relationship between mortality and breastfeeding and specifically said its findings and data should not be used to infer causality.
In short, they used a bunch of statistical weirdness and did at least one thing with the data they were specifically not supposed to in order to make an exaggerated batch of findings.
Six Years Later…
This brings us to the study that was recently published. The results were obtained by running various figures through a simulation that used the country’s 2012 fertility rates and what the researchers considered the most robust statistical associations between breastfeeding and various diseases. The simulation was run based on current, suboptimal, and optimal breastfeeding scenarios. The end result is the above-mentioned figure of saving 2,619 mothers, 721 babies, and about $3 billion in healthcare dollars, all from encouraging better breastfeeding. Sounds too good to be true—probably because it is.
The most basic problem with this study is that it is assuming a stronger causative relation without actual evidence. Several of the conditions described in the research, like hypertension, breast cancer, type 2 diabetes, GI infections, and childhood obesity, have many, many confounding factors, and the influence of breastfeeding on them is either small or unknown. The biggest risk factors for necrotizing enterocolitis, for instance, is being a premature baby with low birth weight—not something breastfeeding can address very directly.
Basically, the simulation’s findings should be viewed very skeptically, since the underlying assumption behind them—that a year of breastfeeding can prevent various conditions that also have multiple other influences—has not been successfully validated.
The Other Problem
The other issue with the study is not so much with the research itself but what it represents: a continued, over-hyped pressure to get people to breastfeed. Do babies fare better when breastfed? According to the most robust data, yes. However, the effect is small and not enough justify the stress or guilt women face when deciding whether or not to breastfeed. There is also some (admittedly contested) evidence that current approaches to encourage breastfeeding may be counterproductive.
Bottom line? Breastfeeding may be good, but it’s not that good, especially not to the point that Bartick and Reinhold’s erroneous simulation describes.
Bartick, M., et. al., “Suboptimal breastfeeding in the United States: Maternal and pediatric health outcomes and costs,” Maternal & Child Nutrition, 2016; 10.1111/mcn.12366.
Bartick, M., et. al., “The Burden of Suboptimal Breastfeeding in the United States: A Pediatric Cost Analysis,” Pediatrics, 2016; http://pediatrics.aappublications.org/content/125/5/e1048.
“UNC-Chapel Hill OB-GYN Dr. Alison Stuebe co-authors new study that shows breastfeeding saves mothers’ lives, too,” UNC Healthcare web site, September 28, 2016; http://news.unchealthcare.org/news/2016/september/unc-chapel-hill-ob-gyn-dr-alison-stuebe-co-authors-new-study-that-shows-breastfeeding-saves-mothers2019-lives-too, last accessed September 29, 2016.
Hall, H., “Breastfeeding Is Good but Maybe Not THAT Good,” Science-Based Medicine web site, April 13, 2010; https://www.sciencebasedmedicine.org/breastfeeding-is-good-but-maybe-not-that-good/, last accessed September 29, 2016.
Hall, H., “Efforts to Encourage Breastfeeding Like the Baby-Friendly Hospital Initiative (BFHI) May Have Unintended Consequences,” Science-Based Medicine, August 30, 2016; https://www.sciencebasedmedicine.org/efforts-to-encourage-breastfeeding-like-the-baby-friendly-hospital-initiative-bfhi-may-have-unintended-consequences/, last accessed September 29, 2016.