A study published last week in Archives of Disease in Childhood is the latest in a long line of research to provide evidence for the benefits of breastfeeding. In the study, researchers analyzed data collected through the Millenium Cohort Study, a long-term investigation of child development that includes a large sample of babies born in the U.K. in 2000-2001.
Parents of more than 9,500 children were surveyed about infant feeding when their children were 9 months old. Then, when their children were 5 years old, the parents completed the Strengths and Difficulties Questionnaire (SDQ), a well-known survey designed to identify behavior problems such as anxiety, hyperactivity, and lying and stealing.
The researchers found that mothers who breastfed their babies for at least 4 months were less likely to report that their children had serious behavior problems at age 5.
How much less likely? Media accounts of the research tended to focus on the finding that 16.1 percent of children who were formula-fed had behavior problems, compared with only 6.5 percent of children who were breastfed.
That’s a dramatic difference, suggesting that formula-fed babies are two and a half times more likely to develop behavior problems. No wonder one reporter suggested that “a woman who chose to bottle-feed would have to be a real boob”, a phrase that caused me to suck in my breath in shock—I like a bad pun as much as the next person, but wow, that does not move the conversation forward.
The problem is that these raw numbers don’t take into account factors such as socioeconomic status or maternal education level. That is, children from poorer families are more likely to have behavior problems, and poorer mothers are also less likely to breastfeed. Previous studies have found that once such factors are statistically accounted for, differences between breastfed and formula-fed babies often shrink or disappear.
That seems to be what happened here, though the study authors don’t help us much by presenting page after page filled with tables of odds ratios, which have been called “Possibly the most difficult concept to grasp when reporting research findings”. But according to study leader Maria Quigley of the National Perinatal Epidemiology Unit at Oxford University, after accounting for these other factors breastfed children were still 30 percent less likely to have behavior problems.
So breastfeeding has modest but statistically significant benefits: no surprise there. Whenever I read such studies, I feel like they are missing the point. Our collective conversation about breastfeeding versus formula-feeding tends to focus narrowly on numbers. It focuses much more on babies than on mothers. And it ignores what science can’t capture very well, but what is one of the most salient reasons to support breastfeeding: simply, that many women find it enjoyable, valuable, and rewarding.
(To be sure, some women find breastfeeding tedious, not worth the tradeoffs, or outright logistically impossible. But few of them just don’t care about its benefits.)
Most parents just want to raise their kids in a way that feels natural, congenial, and fulfilling to them. So by all means, let’s encourage more women to nurse their babies. But by “encourage” I don’t mean “harangue,” I mean “genuinely make it easier.”
Sarah DeWeerdt is a freelance science writer based in Seattle, Washington. (She also snapped the photo.)
I’m interested in that SDQ test, Sarah. It’s filled out by parents reporting on their own children? That’s 30 percent right there.
Thanks for taking such a balanced perspective. I think you’re right that taking the focus away from the mother causes people to miss the big picture.
As Hanna Rosin wrote in the Atlantic, “when people say that breast-feeding is “free,” I want to hit them with a two-by-four. It’s only free if a woman’s time is worth nothing.”
Ann, yup, parent self-report. I understand why large population-based studies do this, but you’re right that this introduces potentially a lot of bias. I hate to admit my own lack of objectivity, but I’m pretty sure my answers to those questions would vary from week to week.
Jessa, thanks for your kind words. I was thinking about Hanna Rosin’s piece when I was writing that post. I had forgotten until I went back to read it yesterday that she winds up in a similar spot as I do–with the sense that a big reason women breastfeed, despite the challenges, is that there’s something ineffable and almost magical about it. But the article really irritated me when it came out! She argues against breastfeeding on feminist grounds, but spends all this time on a takedown of studies purporting to show breastfeeding’s benefits, which doesn’t move the conversation beyond that focus on statistics. I feel like that strategy is just bound to make society less inclined to support women who do choose to breastfeed. Imagine your boss telling you, “Eh, breastmilk isn’t really better than formula, so no, I’m not going to allow you breaks to pump.” THAT’s a feminist result?
As a mother who breast-feeds my twins together several times a day (one on each breast) I’ve thought about this study. I believe one reason why breast-feeding is good for brain development is that it involves a lot of close hugging and physical contact, more so than if you give your baby a bottle. Physical contact is known to be crucial for brain development. That said, I have every sympathy for mothers who aren’t able to breast-feed: for something so natural, it’s tough to do. It took me a great deal of effort and persistence to teach my babies to breast-feed. (They were born eight weeks premature and had not developed their sucking reflex at birth.) I also supplement with formula. Preachy people should back off because the most important thing a parent can do for their baby is help them grow with love.
P.S. I should have written that I breast-feed my twins several times a day AND NIGHT. Yrs, sleep-deprived Mummy
Whoa, Josie, two at a time–that is impressive! I’m so interested in what you are saying about the difference in physical contact between breastfeeding and bottle feeding. In the past, I have kind of dismissed that argument, because I figured if you’re giving a baby a bottle you’re still cuddling and interacting. But it sounds like you feel like there’s a difference in the level of contact/interaction when you’re nursing your twins vs. giving them a bottle–that is fascinating. There are a lot of subtleties here, I think.
Dear Sarah,
Thanks for your kind words! It took a great deal of effort and persistence to feed both babies together but it’s worth it because it saves some time if I feed them together than if I feed them one after the other. It is I should say one of my prouder achievements in life.
With breast-feeding, cuddling them close comes with territory, as it were. With a bottle, you can certainly hug them close when you feed a baby. But you don’t have to. You can prop them up in a bouncy seat and give them the bottle in your hand without holding them, or as my husband does, prop the bottle up on a towel on their chest so that they “auto-feed.” (He is an engineer).
I haven’t read the original report so I don’t know whether the authors considered the effect of cuddling while breast-feeding, which would have nothing to do with the nutritional content of the milk. I think it’s an important consideration. Good blog post, by the way. Thanks! Josie
“Auto-feed”–that is too hilarious! Funnily enoguh, I posted a link to this blog post on my Facebook page, and a friend of mine commented that she had read the post while breastfeeding her newborn (and then one-hand-typed a message to me). So there’s one bit of evidence that people can find ways to multitask regardless of feeding method!