Category Archives: science

Breastfeeding might not protect kids from obesity. So what?

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The past few days have produced a flurry of articles on how breastfeeding may not protect against obesity. You’d think I’d be shouting an obnoxiously loud DUH or TOLD YOU SO. Instead, I want to poke my eyes out and claw at my ears until they bleed. That’s maybe slightly dramatic, but seriously – I’m at my wit’s end, here.

The truth is, there have been quite a few studies and reviews that showed negligible or conflicting results regarding the effect of infant feeding practice on later obesity (ie, this one, this one, or this one). That hasn’t stopped numerous government or health organization from urging us to support breastfeeding because it will solve the obesity epidemic, opting to focus on this convoluted claim rather than the myriad of health benefits that have been repeated consistently over metastudies and reviews (i.e., lower risk of gastrointestinal infection, lower risk of ear infections, hell, even the IQ thing is more soundly supported by the research).

I get why there’s more attention being paid to this finding – it comes from the PROBIT study, which is the closest thing we have to a randomized, controlled experiment in the infant feeding world (other than sibling studies, of which there have been exactly two- at least that I’ve been able to unearth). For those who don’t spend their free time reading the canon of breastfeeding research, let me give you the Cliff’s Notes: PROBIT was a study undertaken in Belarus, which had low breastfeeding rates at the time. They took a cohort of pregnant moms and gave one randomized group more intensive prenatal breastfeeding education and baby-friendly hospital etiquette when they delivered; the other group got the status quo by way of breastfeeding support. The thought was, the group that got better education and support would breastfeed more exclusively and for longer; the other group probably wouldn’t.

Are you confused? You should be. The thing that puzzles me (and hopefully you as well) is that while this plan might have convinced more women to initiate breastfeeding, the same pitfalls that plague all breastfeeding research still remain. Some of the women in the “breastfeeding friendly” group still – presumably – could not breastfeed for physical reasons, others may have chosen not to. All this study can really show us, after all the necessary confounders are accounted for, is whether this type of breastfeeding promotion and support can increase breastfeeding rates. Otherwise, it’s basically more of the same. There are still fundamental differences in the women who were able to breastfeed and those that couldn’t/didn’t.

But, for whatever reason (desperation?) the medical and advocacy communities have grasped onto PROBIT as the Holy Grail of irrefutable breastfeeding science. So, if PROBIT shows that breastfeeding confers no protective effect against obesity, that means something. (Incidentally, as the babies involved in PROBIT get older, I’m sure we will see a lot of headlines on the long-term effects of breastfeeding… so if you’re interested in this stuff, try and familiarize yourself with it now. Here’s some good literature on it, to get you started.)

While I believe, based on my reading of additional research into the obesity link (more on this in Bottled Up, not that I’m plugging my book or anything. I mean why would I have to, book sales being as horrible great as they are?), that there truly is little to no advantage to breastfeeding in regards to later obesity, there’s no excuse for bad science or bad reporting. And this, my friends, is a both. We are taking ONE finding from ONE study – a well-designed one, to be sure, but far from perfect or immune from the problems plaguing most infant feeding research- and proclaiming its results as absolute truth. The sad thing is, some of the biggest breastfeeding advocates are just as guilty of this as the knee-jerking media: Dr. Ruth Lawrence, one of the founders of the Academy of Breastfeeding Medicine, even admitted that she was “disappointed” about the result (although as someone so wisely pointed out on our FFF Facebook page, how freaking ridiculous is it that she is “disappointed” to find out that the vast majority of Western babies – being that they are nearly all at least partially bottle fed – are not doomed to a life of morbid obesity just because their mothers were “suboptimal” breastfeeders?? And what does this suggest about the inherent bias of breastfeeding researchers?).

The near-hysteria surrounding this finding is just further evidence of how warped our thinking is around infant feeding. Why is it such a big deal that breastfeeding doesn’t solve the obesity epidemic? Because we’ve made it a big deal. We’ve built a house of cards on top of this one health claim: it’s the basis of the First Lady’s push to support breastfeeding; Mike Bloomberg has used it to justify locking up formula in NYC hospitals; pretty much every article about breastfeeding in the past year has suggested that formula fed babies better start saving up for Lap Band surgery. The grotesque amount of fat-hating aside (because if you think formula feeders have it bad, you should see how awfully we treat overweight people in our public health discourse), it’s ridiculous that we’ve focused so much attention on this supposed benefit of breastfeeding when common sense says that our nation’s growing waistlines are due to a multitude of factors – genetics, cultural differences, lack of clean air/safe streets/room to move in our cities, processed food, sedentary lifestyles, the time we waste on the (ahem) internet….

My hope is that breastfeeding advocates and health officials might learn from this; that they might take a step back and reassess the way they are promoting something that should be a basic human right as a medical necessity. But at the very least, I hope this will be a cautionary tale for those of us who strive for critical thinking to remain skeptical of absolutism, in both science and in life.

 

The two headed chimera of infant feeding studies

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It’s been a crazy week here, and I was really hoping to pull some pithy, short post out of the exhausted recesses of my brain. So when a study came across the wire touting extended formula feeding as a risk factor for a certain kind of childhood leukemia, I stuck my fingers in my ears. (Well, I posted about it on the Facebook page, but that’s kind of like the passive aggressive form of social media, isn’t it?) And a day or two later, when the Interwebz started buzzing about the British version of the infamous Burden of Suboptimal Breastfeeding “study”, I shoved a pillow over my head and sang the soundtrack of Beauty and the Beast really loudly (that’s what’s popular with the Fearless Children these days. It’s a great soundtrack and all, but seriously, how many times can a person hear Be Our Guest without going nuts? Although I did recently discover this YouTube gem, which has given Little Town – or, as Fearlette calls it, “Belle Sahwng” – a whole new meaning…).

One is named “Twitter”, the other “Parenting Science”

Unfortunately, I’m realizing that there is far too much inaccuracy and fear mongering going around to ignore. I don’t think I have the mental capacity to write a whole long diatribe, but I do want to address a few memes that are spreading like a California wildfire.

Courtesy of the UNICEF “Preventing disease, saving resources” report, I recently saw a discussion of how in the UK, only 1% of women are breastfeeding exclusively at 6 months. The consensus was that since formula feeders are so obviously in the majority, there is no need for them to feel marginalized.

I was shocked at that 1% statistic, and when I first heard it I was seriously blown away. But let’s look a bit closer at what the report actually says:

“….the proportion of women still breastfeeding at six weeks after birth increased by only a few percentage points between 2000 and 2005 – to just under 50% (Bolling et al, 2007). Rates of exclusive breastfeeding are much lower – only 45% of women reported that they were breastfeeding exclusively at one week after birth; fewer than 1% were still doing so at six months (Bolling et al, 2007). The rapid discontinuation of breastfeeding in the early days and weeks after birth, seen consistently since national surveys began in 1975, has only marginally improved to date, demonstrating that women who start to breastfeed often encounter problems, whether socio-cultural or clinical in nature, and stop. Ninety per cent of women who stop breastfeeding in the first six weeks report that they discontinue breastfeeding before they want to (Bolling et al, 2007). As a consequence, women can feel that they have failed their babies (Lee, 2007), and the great majority of babies in the UK are fed with formula in full or in part at some time during the first six months of life, and by five months of age, 75% of babies in the UK receive no breastmilk at all.” (p. 35)

First things first: notice the amount of 2007s in that paragraph. Yup, the stats they are citing are from a 2007 report, which offered statistics gleaned from a 2005 infant feeding survey. 

Aw, come off it FFF, 2005 wasn’t that long ago.  Things can’t have changed all that much in 7.5 years. 

Well, let me just say this: I want to see statistics from at least 2010. (They have them, but these 2010 survey results do not include information on duration, just initiation.) I have a gut feeling, from my reading of the research and observations I’ve made from the sheer number of emails I get from our UK sisters, that things have changed. In a Twitter conversation tonight, someone with an adolescent son mused that if social media had been around when she was a new mom, her postpartum experience would have been markedly different. The advent of social media has changed the infant feeding world – yes, it may only be on a sociological level, and we may not yet be seeing huge statistical jumps in breastfeeding rates, but both breastfeeding awareness and pressure have increased since new mothers began spending more time on Twitter and Facebook than in mommy-and-me groups, or with their sisters, friends, or mothers.

Additionally, the last sentence of the paragraph – perhaps the most jarring- carries no citation. If we don’t know what they are basing this on, it’s hard to say if it’s hard fact, or merely an assumption by the authors. (Oh- and that reference to women feeling like they have “failed their babies” rather diminishes its citation, Ellie Lee’s landmark 2007 paper about how morality plays into the infant feeding debate. From what I gathered from her work, these women do feel they failed their babies when they switch to formula because they are MADE to feel that way by society- not because they have an innate sense of wrong-doing. I think this allusion ignores a large piece of the puzzle, and allows the authors to pay lip service to formula feeders while simultaneously perpetuating the cycle of shame. Then again, I’m already ornery, so maybe I’m over-analyzing this.)

What strikes me as odd is that I recently saw this press release, also from Unicef, applauding NHS for achieving a landmark: 8 out of 10 British babies are now breastfed, thanks to the Baby Friendly Initiative. Obviously, this is referring to initiation rates, not duration, so it’s apples and oranges. Any yet, the difference in tone confuses me – if the rates are going up, and it’s a cause for celebration, why the pessimism in this new UNICEF report?

I don’t doubt that UK breastfeeding rates are lower than most Western nations. That’s been the case for awhile. But even in Norway, exclusive breastfeeding rates at 6 months are pretty abysmal. That’s because… wait for it… most babies have received some solids by then. Even before the 6-month “ready for solids” party line started being questioned, most moms were letting their babies try a bit of rice cereal or some veggies between 5-6 months. Exclusive breastfeeding means exactly that – exclusive. As in NOTHING BUT BREASTMILK. This 99% of women not exclusively breastfeeding at 6 months back in 2007 was not necessarily a group of supplementers or early weaners – they could just as well have been people who cheated a bit on the 6-month rule for solids. (And more power to them if they did, considering some experts – and many moms- believe that when to start solids should be an individual thing, and based on a baby’s readiness anytime between 4-6 months).

The thing that scares me is that this paragraph – oh bloody hell, this whole report – is based on the assumption that no journalist or policy maker is going to take the time to dig up every cited study, or to pay attention to where the statistics are coming from. I would say the majority of people (shall we say 99%?) are going to assume that this paragraph translates to only 1% of women nowadays, in 2012, are making it to 6 months without using formula and that, my friends, is simply not the case.

Stupid thing to obsess about, right? Well, it might be, except this kind of confusing rhetoric is used throughout the report. They make a big stink about only using “quality” evidence, stating that the costs to British society would be far greater if they were able to use the plethora of less-conclusive scientific literature which links “not breastfeeding” (the word “not” is italicized every time it appears in this context. Kinda weird…) with things like ovarian cancer, SIDS, adult obesity, and Celiac disease. As it stands, they have calculated the health care costs of treating diseases primarily seen in non-breastfed babies: ear infections, gastrointestinal infections, respiratory disease, and necrotising enterocolitis, as well as breast cancer in mothers.

But what exactly does this “robust evidence” consist of? The authors thoroughly vetted the studies they used to determine the rates of specific diseases – so much so, that the outcomes were often based on one or two studies (like in the case of ear infection), as well as a few used for “corroborative evidence”. This report was not trying to determine the quality of breastfeeding research, nor does it purport to offer new evidence for the correlations they site. Rather, they are simply going through, deciding which studies to use based on specific criteria, and using those outcomes to determine economic savings.

(FYI, the authors admit that they leaned heavily on the Burden of Suboptimal Breastfeeding methodology to calculate their own costs. Please refer to our friend Polly over at MommaData for a good breakdown of why this method is inherently flawed.)

The report, which was distributed to and covered by every major media outlet in the UK, is lengthy and exhaustive – great for researchers, not so great for journalists. I doubt many who reported on this study read all 104 pages, including citations; I doubt many understood that the goal of the report was not to determine whether any of these conditions are actually caused by not breastfeeding versus being a matter of correlation too muddled by confounding factors, but rather it went under the assumption that these diseases/conditions were in fact PROVEN to be directly influenced by suboptimal breastfeeding. Get it? Report= economic case for breastfeeding. This is not a study proving anything new.

I admit that this report is far more palatable than its Yankee counterpart. There is legitimate attention paid to why women aren’t breastfeeding, and it even references studies and literature about the guilt and feelings of failure which occur when women cannot breastfeed (if somewhat incorrectly – see above reference to Ellie Lee). I appreciate that. But just as I worried (justifiably, it seems) with the Burden of Suboptimal Breastfeeding, I fear that this will be adopted into the infant feeding canon, and used incorrectly to support a myriad of other studies. This is how it works, unfortunately.

I also want to mention that the lead author of this study is Mary Renfrew, who has been quoted as saying that “women are born to breastfeed”. To me, this rings of bias, which can easily lead to confirmation bias. And when you’re basing a report on the opinions of a few key people as to what is considered “quality” evidence… I wonder if a neutral party would have given this study more gravitas. Good luck finding a neutral party in this field, though…

Moving on. The next hot new thing on my Twitter feed is a study which links childhood leukemia with a longer duration of formula feeding. This study may very well be credible. I have no idea, and neither does anyone else commenting on it – because it isn’t published. It isn’t even peer reviewed. And yet it is flying through the airwaves, causing squeals of “formula feeding causes cancer!!” in a manner that echoes with thinly veiled I-told-you-so’s.

But that’s not even the interesting part. Let’s go under the assumption that this study will come out and be stellar and scientifically sound (because we can’t really do anything in terms of dissecting it until we can see the damn thing, anyway). According to the study, do you know what also carries a comparable risk of childhood cancer development? Later introduction of solids, regardless of infant feeding method. Breastfeeding alone did not have a significant effect, but rather the length of time using formula, and the length of time the child went without solids in their diet.

I haven’t seen one freaking tweet about the solids thing. Not ONE.

I may well be a Defensive Formula Feeder, as one beloved lactivist blogger has knighted me, but here’s what I don’t get: one of these (assumed) correlations supports advocating for an act which often involves major social, emotional, physical, and economical sacrifice on the part of women. (It shouldn’t, but right now, in our society, it often does.) The other correlation just implies that you need to start giving Junior a daily dose of butternut squash around 6 months of age. Why are we so focused on the one that is complicated by socio-biological factors, and not one the one which would be easy for most parents to incorporate into their child-rearing?

I’m not pissed about the studies, people. I’m pissed because THIS is how we’ve arrived at this place. This place where women are being pitted against each other; this place where we are made to feel responsible for the wealth and health of the nation, so that our governments can spend a few bucks pressuring women to breastfeed rather than figuring out real ways to enhance socioeconomic disparities; this place where one can’t question the intentions or quality of a research paper without being accused of being anti-breastfeeding or anti-mother or anti-science.

Speaking of Beauty and the Beast…this game of championing-research-which-can-mislead-and-and-scare-new-parents-before-stopping-to-fully-comprehend-it reminds me of The Mob Song (my son’s favorite). As the townspeople march towards the Beast’s castle with fiery torches, they sing: “We don’t like what we don’t understand- in fact it scares us, and this monster is mysterious at least… here we come, fifty strong, and fifty Frenchmen can’t be wrong…”

Imagine those Frenchmen with Twitter and Facebook accounts, multiply them by about 1000, and you have a great explanation of what’s wrong with social media and parenting science, my own personal two-headed Chimera.

 

 

 

A couples therapy session for Science and fed-up parents

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You know how I’m always harping on and on about how we could be doing studies that actually help us protect infant health, rather than guilt-tripping mothers? My fairy godmother must’ve been listening, because today I stumbled upon an interesting article, courtesy of Mammals Suck (maybe she is a fairy godmother? Scientists can be fairy godmothers, can’t they?)

Featured on Nature.com, the article described two findings about the sugars in breastmilk. The first discovery was that one of the human milk oligosaccharides (HMOs) – the sugar molecules present in breastmilk -  can actually increase the chance of mother-to-child HIV transmission.

The molecule, called 3′-sialyllactose (3′-SL), is found in varying concentrations in the milk of different women. In a study in Zambia, HIV-negative newborns breastfed by HIV-positive mothers are twice as likely to catch the virus during their first month of life if the mother’s milk has an above-average level of 3′-SL1.

Doesn’t sound like the most positive news, but wait: only certain women’s milk contains significant enough levels of the sugar to place their babies in danger. Plus, other sugars have a positive effect:

The same study in Zambia found that five more of the 150-odd complex sugars in breast milk seem to have a protective effect. HIV-negative infants who consumed these sugars had a better chance of reaching their second birthday than did HIV-negative babies who drank breast milk lacking those sugars irrespective of their mothers’ HIV status. (Once a baby had caught HIV, however, breast-milk sugars had no influence on survival.)

 

The second part of the article described research into why some babies are not able to fight off necrotizing enterocolitis (NEC), despite being fed human milk. Breastmilk contains oligosaccharides that fight off this deadly infection – but as it turns out, not all women produce these sugars:

 (A team) reported an association between a dangerous gut disease in babies called necrotizing enterocolitis (NEC) and the inability of affected infants to secrete a suite of oligosaccharides in their mucus. These babies are considered particularly likely to benefit from drinking the sugars via breast milk, but about 10% of European women cannot make them in their milk…

 

Okay, so this is where it gets really interesting. Both of these examples suggest that depending on the composition of a particular woman’s milk, the health benefits of breastfeeding may not be identical across populations. A researcher quoted in the article hypothesized that “(t)he often confusing literature on breast feeding’s impact on disease will be largely explained by this underestimation (of the variation in human milk).” The article also explains how “(s)everal labs are trying to identify how variation in the prevalence of the large sugar molecules in breast milk… influences infant health. Once clear links are established, clinical trials to test HMOs as health-boosting additives in infant formula milk can be drawn up.”

Say WHAAAAAAAAT??

Yep, you read it correctly, FFFs. And I think we can all take a moment for a collective sigh of relief. Not all researchers are so entrenched in their  public policy advocacy efforts that they forget to see the forest for the trees! Not all lactation scientists are lactation consultants! Some are – dare I say it – scientists.

I fear that this is the type of research that gets pushed under the rug, because it requires critical thinking. There isn’t an easy soundbite that can appeal to the masses – in the first example, the answer is not to tell HIV+ women in developing countries to use formula until they are tested for the specific HMO, because formula feeding in resource-poor countries with contaminated water is a high-risk activity. But perhaps more research could lead to some sort of treatment which would help these women lower their levels of 3′-SL and increase the beneficial HMOs.

Similarly, what if a preemie’s mom wanted to get her breastmilk tested to see if it contained the necessary HMOs to protect her baby? And if she found that she was part of the 10% who didn’t produce these beneficial sugars, perhaps that could allow her to make an informed decision about using donor milk, while either pumping to keep up her own supply, or deciding to switch to formula once the baby was older.

Research like this allows for progress. It allows us to understand exactly what it is about breastmilk that makes it so beneficial, which might lead to better, more biologically “equivalent” options for women who can’t or choose not to breastfeed. But even taking it away from the infant feeding choice powderkeg for a minute, I think it’s an interesting thing to ponder why certain people are so uncomfortable with the suggestion that not all breastmilk is perfect milk. I mean, I understand it – who the hell is science to tell a woman that her milk isn’t “good enough”?

But people – this is exactly why we can’t be wishy-washy about whether breastfeeding is a personal act or a monitored, medicalized event. If we are going to pitch it to women based on statistics, telling parents that science has proven the medical necessity of nursing our young, then we must accept the risk that science could turn around and say “erm, you know what? I messed up. That’s only true for some women. Some gals just produce inferior milk.” While we might want to say screw you, science, and the horse you rode in on, we can’t. Because we used science in some very dirty ways when it suited our needs, and now it is hanging around like a rebound boyfriend who just doesn’t take a hint.

On the other hand, if we don’t allow medical authorities to lay down moral indictments based on the way we feed our babies, then we can easily kick science to the curb when it tries to tell us that our milk may not be all it’s cracked up to be.

Personally, I don’t think either scenario is great. As that Facebook group with the funny memes says, I f**king love science. Because I don’t think it’s true science that is messing things up for women. I think it is zealotry dressed up as science – people who are so committed to a cause that they are unable to come into research with the open, curious mind so integral to the scientific process.

So, I think as women, as mothers, it is safe for us to applaud research like this. We have to trust that knowledge can be power, as long as it is handed to us free of extrapolation. It’s not scary to hear that formula fed babies aren’t protected from NEC if donor milk is made available to preemie parents, or if we know that good old science is doing its best to create a supplement that could offer our tiniest babies protection regardless of the quality or quantity of a new (and often highly stressed, given the circumstances) mother’s pumping efforts. It’s not guilt-inducing to hear that breastfed babies have a higher IQ if we know exactly why this is – if it is an association, or something about the physical closeness during the act of nursing (which could easily be recreated by a bottle-feeding parent using a bit of imagination and less clothing) or something specific in the milk (in certain milk? Do some women increase their baby’s intelligence, and some women decrease it? Who the heck knows until we look into it?).

We can’t be scared of science, and we can’t abuse it. And scientists can’t be scared of staying neutral, and can’t abuse their power. If we can give each other this mutual respect, maybe we can turn this into a beautiful relationship. Even if it did start out as a rebound…

 

 

Pyloric stenosis and bottle feeding: Vomiting up some logic

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A study published in Pediatrics is claiming that bottle feeding might be a risk factor for pyloric stenosis (a condition in which the pyloric muscle malfunctions and impedes food (liquid) from going down into the small intestine, causing severe projectile vomiting). Actually, if you read the study, it seems that the authors are suggesting that formula feeding may cause pyloric stenosis; they argue that the rate of the condition went down when breastfeeding rates went up in Denmark, and that babies who were formerly breastfed and then switched to formula developed pyloric stenosis after making this dietary change.

The study itself is somewhat convincing. The authors looked at a Danish cohort of 70,148 babies born between 1996 and 2002. Of these babies, 65 eventually had surgery for pyloric stenosis (PS); 29 of these were bottle-fed.

Looking at these numbers, one might be confused – if 29 out of 65 babies were bottle fed, that means the other 36 were breastfed, right? And obviously, 36 is bigger than 29. (I dropped out of math my senior year in high school, but even I know that). However, the art of statistics makes numbers all irrational and annoyingly misleading, and because the number of breastfed babies in the cohort was so much larger than the number of formula fed babies (Denmark has impressive breastfeeding rates), statistically, the formula fed babies had a much greater chance of having PS. A 4.6-fold higher risk, to be exact. Scary stuff.

No need to panic just yet, though. First of all, while the study claims to have controlled for confounding factors, this controlling was based on telephone interviews – some of which were performed retrospectively. This type of data has a bad reputation in the research world, because, in the immortal words of Dr. House, everybody lies. We call it innocuous names like “recall bias”, but it amounts to the same thing. (Think about it: when you fill out those health forms at the doctor, and they ask about alcohol use, do you check “rarely” or “never”? What do those categories even mean? What you might consider “rarely” might be the equivalent of binge drinking to someone else. And don’t even get me started on the questions about smoking. There’s no box that describes “social smoking only when wine was involved in your early 20′s, with the occasional guilty cigarette at times of extreme stress, like once every 3 years”. So I – er, I mean, someone- might lie and say “never”. ) This study was also vulnerable to the same frustrating issues that plague all infant feeding research – it’s impossible to control adequately for everything.

House, MD. Best show ever. RIP.

Even so, there is something suspicious about the fact that when some of the PS babies who were formerly breastfed started formula, that was when they suddenly developed PS. And it’s odd that the babies who were never breastfed had the same risk as those who were combo fed or weaned early. If this weren’t the case, I might argue that it was likely that early symptoms of the PS may have provoked a change to bottle feeding; sometimes parents will end up formula feeding if a baby has trouble eating, or is spitting up a great deal, in the hopes that a gentle formula might do the trick.

What strikes me as problematic about this study, though, is that while the cohort includes a substantial amount of babies, the sample of babies who actually had PS is quite small. I also think there is something to be said for looking at a cohort in a country with high breastfeeding rates – because there must have been a reason that these other moms weren’t breastfeeding. I wonder, for example, if they asked about antidepressant use, or fertility drugs, or other medications that might have been taken during pregnancy and that would also lead a woman to either opt not to, or be unable to, breastfeed? Also, 91% of the babies with PS were male; there must be something either structural, behavioral or genetic in male human babies that predisposes them to this condition. The authors discuss this a bit in the report, and muse that it could be because boys overeat more than girls do (not sure if there is substantial scientific evidence for this claim or not); this would support the hypothesis that it is something in the act of bottle feeding, rather than the milk itself, that is conferring a protective effect.  Lastly, I wish the researchers had thought to ask for reasons why the parents stopped breastfeeding; this might have led to other associations between the PS and feeding issues.

That said, I actually believe that this is one of the better studies I’ve seen regarding infant feeding. The discussion section takes the time to discuss the possible reasons for a protective effect from breastfeeding (or a negative effect from bottle feeding), elaborating on both the milk as a substance (they suggest that babies fed with breastmilk in bottles may be at just as high a risk, and admit that they did not receive adequate info to make a distinction between expressed breastmilk, donor milk, or formula) and on the act of bottle feeding itself. They also state that “formulas have improved over time and now approach the composition of breastmilk” and that this could be “a contributing reason for the decrease in PS incidence.” (And that leads my overtired brain to form more questions… what about the type of formula being given? Were these babies on soy? Formula with or without DHA? Partially hydrolyzed formulas?)

The ultimate consensus of these researchers is that this study “adds to the evidence supporting the advantage of exclusive breastfeeding in the first months after birth”. This is true, but I’m not quite sure it’s helpful, or even that scientifically prudent. If the aim of infant health studies is to improve infant health, wouldn’t it be more substantive to end with something like….

These findings suggest that there may be a protective effect against pyloric stenosis from exclusive breastfeeding, and should encourage further studies to decipher why this may be. Whether the relationship is merely associative, or causal, remains to be seen; further examination of the biological or mechanical  reasons for the reduction in risk might help determine this, and lead to better outcomes no matter what the mother’s choice of feeding may be.

 

And pigs may fly wearing my daughter’s favorite leopard-print tutu.

In sum, this is an interesting study, and certainly leads to some big questions. But considering the total risk for PS was still only 0.1% in the cohort studied, I don’t think it’s something to really worry about as a formula feeding parent. If you have a family history of PS, and your baby is male, you might also want to choose a hydrolyzed protein formula and be extra cautious about over-feeding, as these factors relate to some of the plausible explanations for reduced risk offered by the researchers.

Hope that offers a bit of perspective on a study which associates yet another poor health outcome with formula feeding. Remember, as always, that associations are not causes – and that breastmilk can end up projectile-vomited all over the wall, too.

Mammary Mania: Podcast approaches lactation science as the science it should be

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I just listened to a podcast of a fascinating interview about breastmilk, courtesy of Skeptically Speaking. Interviewer Desiree Schell spoke with Dr. Katie Hinde, an Assistant Professor of Human Evolutionary Biology and the Director of the Comparative Lactation Laboratory at Harvard University. The newest of my internet crushes, Hinde offers a unique perspective on the science behind breastmilk with a level of sensitivity and realism that is unparalleled, as far as I’m concerned.
Take a listen for yourself – it’s well worth the 15 minutes. But in case you just want the Cliff’s Notes, here are the FFF-related highlights:
  • Hinde points out that while there is a good deal of lactation research going on in the world, much of it is agenda-driven. The science is mainly coming from three areas: breast cancer research (which tends to focus on rats, who have similar mammary development to humans), the dairy industry (fixated on how to maximize milk production in cows) and from the infant feeding world (looking at tiny humans and their mothers).  Within the last category, Hinde notes that both sides have clear agendas – one is trying to increase formula sales, and the other has “anti-formula aspects, that no matter what, breast is best.”  “Both ends of these spectrums are limiting,” she says. (To which I say, word. WORD.)
  • Research has shown that milk varies dramatically between women. Some mothers make high fat, low sugar milk; some have more cortisol (a beneficial hormone) in their milk; and so forth. Hinde explains that our milk is affected by what we’ve eaten and been exposed to for years prior to pregnancy and actual lactation, and that these lifestyle factors may create these differences in milk. Even the lactation process can vary across populations – Hinde notes that in America, studies have shown that many women do not have “copious milk production” until 72 hours postpartum, whereas in the less-developed world, the average time is much shorter. Considering doctors often step in at that 72-hour mark and recommend formula supplementation due to fears of dehydration or neonatal weight loss,  it would be highly beneficial to find out why this delay occurs. Hinde questions why there hasn’t been more research on these differences in lactation process and milk constituents among women.
  • While Hinde speaks about the power of breastmilk (and gives a really interesting explanation of just why breastmilk is so miraculous, absent of the usual hyperbole and backed by actual science), she also acknowledges that the decision to breastfeed is not made in a vacuum. And in what is probably one of the bravest statements I’ve ever heard made in a public forum about these issues, she argues that by finding out more about breastmilk, we can then create a better formula. “This is an important goal,” she states, because if women are unable to lactate, or have contraindications like HIV, “we need to make sure that the intervention (formula) is as representative as it can be for what (babies would be) getting from their mothers.” Now, obviously Hinde would argue that breastmilk is a superior nutritional choice, but the fact that she acknowledges the reality that some women are going to need formula, and that we owe these women and their children a better product…. well, let’s just say it made me tear up.
  • On the topic of breastfeeding support, Hinde muses that there is this idea that because lactation has evolved over millions of years, it should be effortless and natural. But “so is sex”, she says, and a lot of us aren’t so great at that to begin with, either. She suggests that by openly discussing the physiological problems so many mothers face when attempting to breastfeed, we could actually increase the amount of women successfully meeting their breastfeeding goals, because we would feel less overwhelmed and lost when these issues arise. (I like to think all of your FFF Friday stories are doing this, in some small way; that they not only make formula feeding moms feel more empowered, but also help women dealing with breastfeeding challenges find answers, solace, and community, as well.)

Dr. Hinde is exactly what is needed in the world of lactation science – a true scientist, able to approach her research with nuance and a wider perspective.  Check out her blog, Mammals Suck…Milk and take a listen to the Skeptically Speaking podcast (Schell, the interviewer, is also pretty darn rad, and manages to guide a potentially science-y interview into a very accessible and entertaining listening experience) to gain a far more thorough understanding of mother’s milk that makes you think instead of wanting to hurl your computer at the wall.
Speaking of thinking, this interview made me ponder about the types of studies that would be truly helpful for infant feeding research. How about a large study examining differences in children of non-breastfeeding mothers, randomly and blindly assigned only expressed donor breastmilk from bottles or a DHA/ARA containing, partially hydrolyzed formula (since this type seems to be the one that fares best in the studies which have been done), essentially ruling out all confounding factors? Or, what if we did intensive interviews and examinations with women who suffer from insufficient milk or delayed milk production, compared to controls that have no problems? Looked into their social, emotional and physical histories, and tried to find a common thread. I’d also love to see studies of breastmilk composition from women on severe elimination diets compared to those with healthy diets. And the list goes on…
So, let’s play scientist. What types of studies would you like to see in the field of lactation science? What do you think would actually help women to breastfeed, or to make formula a better substance?
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