I do realise that I seem to be falling into a pattern lately of devoting this blog to replying to comments on the Fearless Formula Feeder's blog, but this one couldn't be allowed to pass, and the reply I wrote (even though it was shorter than the post I'm going to make here) was still too long to post as a comment, so... sorry about the déja-vu-all-over-again factor. At least this time it's a reply to someone other than Alan. Variety is the spice of life, and all that.
Anyway, the comment that Anonymous posted was a link to this infamous lactivist article, an essay by Ann Calandro entitled 'Even the Occasional Bottle of Formula Has Its Risks: The Case of the Virgin Gut'. (Alternatively, for anyone who felt that title didn't do quite an effective enough job of instilling fear into the heart of any woman daring to think of sullying the purity of her breastfed baby's body with a one-off bottle of formula, I've also seen it posted under the title 'Yes! Just 'One' Bottle Of Formula Will Hurt', by someone who apparently doesn't quite grasp the appropriate use of the subjunctive.) The article is packed with unnerving comments:
Since my baby had received lots in her stomach besides breast milk, her little gut was not virginal. What did this mean? Had the hospital nurses inadvertently done some kind of damage to her? Had I? What was going on inside my little girl?
But what happens when breast milk is not the only food in that little gut? The truth is very interesting and also very scary.
...destroying the characteristic intestinal flora of the breast-fed baby. [This one was a quote from a breastfeeding book.]
...there is very little that can be done to remedy the situation and save the virginal gut.
A huge increase in diarrheal diseases occurs in babies who do not have optimal "intestinal fortitude," which is only possible with guts that have never been exposed to infant formula.
Not to mention, of course, the story of the baby who had a few innocent-seeming bottles of formula and then developed a severe allergic reaction to cow's milk and was rushed into hospital and had stacks of medical tests and nearly DIIIIIIIEEEEED, all because of that scary formula. If you can make it through that lot without being reduced to a quivering wreck at the prospect of your baby possibly ending up consuming some formula and being irrevocably damaged, you're a much more confident mother than I was in those scary first-time-around days. It's thanks to that article, and others like it, that breastfeeding my first baby was turned from the pleasant and relaxing experience it should have been to a miserable, anxiety-ridden chore haunted by the fear of dire consequences if I fell down on the job the least little bit.
Which is terribly sad. Because - surprise, surprise - despite Calandro's claim that there is 'much research to support avoiding supplementation if at all possible', the available evidence doesn't really seem to support her alarmist tone.
There's not much back-up, for example, for the claim that risks of diarrhoea are hugely increased. A study in New Zealand in the late '70s comparing babies receieving various amounts of formula in their diet with exclusively breastfed babies (Fergusson et al, the Australian Paediatric Journal, 1978, vol 14(4), pages 254 - 8) found that giving some formula supplements to breastfed babies on an irregular basis carried slightly greater than a one in twenty chance of causing diarrhoea. Now, those were the figures unadjusted for possible confounders, so that will in fact be an overestimate – and it's still hardly the 'huge risk' claimed by Calandro. And that, of course, is more than thirty years ago, when sterilisation techniques were poorer than today. What do more recent figures look like? Well, a 1997 study available in Pediatrics looked at the infection rates in babies receieving different proportions of formula in their diets. Babies getting formula supplements up to around 10% of their total diet showed *no* increase in rates of diarrhoea over babies who were exclusively breastfed. Seems like all those babies were somehow managing to do just fine despite the defloration of their precious virgin guts. Maybe getting a bottle of formula now and again, despite what it might do to bacterial counts, is actually not such a big deal in terms of outcomes that actually matter?
As far as the risk of cow's milk allergy goes, a couple of studies have indeed shown a small risk of cow's milk allergy associated with early formula top-ups (in the one for which I have figures, the risk of developing some sort of later reaction to cow's milk as a result of having had some in the hospital was around one in forty), but the research is actually quite conflicting – another study showed negligible effect, and a randomised controlled trial actually showed a marked decrease in risks of milk allergy in babies with a strong family history of allergy who received formula before having any breast milk. So that one is a possible risk, but far from conclusive. As for other forms of allergic disease, again, two studies into the effects of early cow's milk exposure haven't shown any increase in later risk of allergies.
The increase in risk of developing Type 1 (insulin-dependent) diabetes does seem to be backed up by better evidence, but needs to be kept in perspective – this is effectively only going to be an issue for children who are genetically predisposed to develop Type 1 diabetes in the first place. In other words, only a tiny minority. If your baby has a close family relative with Type 1 diabetes, it's probably worth trying to avoid any formula in the early months. If not, then this one is a negligible enough risk not to be worth bothering about.
It's fair to say that the available evidence, despite what Calandro and her ilk claim, is in fact fairly limited, and can't currently exclude a small chance that there might be risks associated with even the occasional bottle. If so, they certainly don't appear to be wildly significant in practical terms, and neither the evidence for them nor the likely magnitude of them justify the kind of scaremongering Calandro is indulging in. If the only reason you're giving a bottle is to get your baby used to one, then I think it's probably worth trying to pump a couple of ounces of milk for that, if possible, rather than giving formula, and I would have liked to see FFF mentioning this possibility in her post. But, for those parents who've already given or need to give their breastfed babies some formula now and again, do I think that these uncertain and largely theoretical risks are worth getting worried about? Hell, no.