I was recently asked to comment on the use of probiotics and prebiotics preconceptionally, during pregnancy, while breastfeeding, and to the newborn. The questioner wanted to know which, if any, probiotics I recommend over others. What follows is adapted from my reply.
Probiotics, probiotics and synbiotics are discussed in Milk matters at more length than I will do here.
The deliberate addition of particular living organisms to infant food is a whole new world-changing experiment which is taking off globally without rigorous independent investigation and controls (as infant formula did). Look in any pharmacy and see the incredible range of products now available. Would parents rush to add ‘probiotics’ to their babies’ food if they stopped to think about probiotics as bacteria/germs, which are living organisms with their own agendas for survival and growth, organisms that require to be fed? Would they add GOS and FOS to the babies’ diet if they realised GOS is derived from milk (galacto- sugars) and FOS from a huge range of sometimes odd carbohydrate sources? Do parents of allergic children realise that probiotics can contain undeclared common allergens like milk and egg? After generations of extolling breastmilk as sterile (which it never was) why are we now convinced that breastmilk’s complex mix of hundreds of species of microbes needs modifying? Why do we trust a whole range of industrially produced organisms (many produced by genetically-engineered organisms, all needing to be highly purified) about which all we can say for certain is that we don’t think they will do harm, and we think that some might do some good – though we don’t know how they might develop and evolve in infant guts over time. (Oh, and by the way, what is true of any one species or mix of probiotics in any one study is not necessarily true of any other species or mix of species. And it is reasonably certain that any mix proved beneficial will be patented and expensive. And if recent research is proved right, it may be possible to use killed, not living, microbes to produce immune effects, which would seem a lot safer – provided that the species used do not evolve to produce toxins that persist after their death, as Botulinum species can.)
All of which makes it clear that this is not a simple matter.
The addition of ‘synbiotics’ (bugs and their food) to infant formula will definitely alter gut microbiomes, some of which may need to be changed, and some of which may be worse for the change. If putting microbes and their food into infant formula improves infant digestion of those less digestible mixes, it’s probably a good thing. But hadn’t we better follow all those experimented-on children to see the long-term outcomes of specific organisms in specific mixes? And then compare them by species and strain and formulation? Of course, if they do work in infant formulas, it will be only at certain temperatures and concentrations, and so preparing infant formula in the way that protects the patented bugs might also increase the risks of growth of other harmful bacteria – possibly present in always unsterile infant formula powder, or contaminating liquid ready-to-feed products once they are opened. And as a Cochrane review indicated, some adverse events have been found; “some case reports of infections and bowel ischaemia caused by probiotics.” see https://onlinelibrary.wiley.com/doi/10.1002/14651858.CD006475.pub2/abstract
Does it help to give such bugs to mothers in pregnancy? Again, we don’t know, and this generation are the guinea pigs who will help us find out. Perhaps women who are the victims of past formula feeding, with their distorted gut microbiota, will benefit, and their babies postnatally as well. There is a possibility that the already-allergic might be helped. But helped by some specific organisms, which are not necessarily the ones mothers can pick up in local pharmacies. And of course giving large quantities of any living bacteria is going to alter the balance of other bacteria in the body, just as planting a forest of pine trees leaves the landscape looking green, but lowers its biodiversity with drastic results for some other living things in the area. There will be changes, but no one knows what they will be: at present it is said that science has characterised only about 10% of the human gut microbiota responsible for the all-important healthy gut microbiome. It might be a good idea to know what’s there before we change it?
Would I suggest giving probiotics to exclusively breastfed babies? Not unless there was some good gut-based reason to consider the matter, like the infant having been exposed to infant formula or fortifiers or antibiotics neonatally, with ongoing evidence of gut distress and abnormal stooling, say. Would I suggest smearing bacteria on nipples? Never, until we have good studies about how they act and interact and evolve in that environment of maternal skin, so different from the human gut, and what effects they have on infant oral surfaces in such doses.
Would I suggest any particular probiotic? For allergy prevention, Lactobacillus Rhamnosus GG in pregnancy seems to have the most -not entirely convincing – evidence, though of course virtually all evidence is funded by vested interests. However, when it comes to the science of infant formula generally, Nestlé makes the results of scientific research far more publicly available in an apparently uncensored form than many competitors, the quality of whose research I cannot judge, when only press releases or summaries are on their websites, or access is restricted. That fact doesn’t mean I approve of Nestle or their infant formula; it just means that I know it’s utterly wrong to believe or say that “formula is all the same because it has to fit the regulations.” It isn’t. [Regulations are often set wide enough to accommodate existing products, and each variety is different, even each form (powders/liquids) of each brand, and each batch of each form can vary too. Different processes and temperatures have different results. So after all that I have read in 40 years of focus on formula, I don’t know which formula is better than any other. Nor do I know anyone else who does. Comparative carefully monitored trials have never been done! I would however suggest parents use only a Stage 1 product, as the others are designed only for use with other foods, i.e. they don’t even pretend to supply all that a baby needs. I also suggest that parents choose the formula with the lowest protein level, as even that is still much higher than breastmilk protein levels. And I would choose a high volume product made in a modern factory by one of the major global manufacturers, not one of the new entrants to this booming market. Why? because I suspect that numerous pitfalls of formula manufacturing are better known to those who’ve been doing it longer.]
Despite all the above, I know that some mothers report that giving probiotics seems to help their hypersensitive baby, improving what seems like slow stool transit times and difficulty pooing. This is all anecdotal, and no one can repeat the experiment or control for the effect of “the tincture of time.” Strains isolated from breastmilk intuitively seem like a safer option than strains isolated from other sources; however, we need to know how the final powder comes about, and what other ingredients, including allergens, it may contain, before feeding it to the very young infant. Ideally probiotics would be prescribed with before and after faecal samples being taken and characterised; but commerce is well ahead of independent research and medical practice. Government regulators and paediatric authorities alike are playing catch-up on this issue, leaving many questions of safety, efficacy and advertising ethics to industry. No wonder mothers are confused. Fortunately, babies are programmed for survival and can cope with a remarkable range of microbial challenges. So mothers who have experimented with no obvious adverse effects need not be concerned. All the same, it might be a good idea to record exactly what product was given and when, in case new and relevant knowledge emerges about consequences.
The only probiotic I can recommend wholeheartedly is breastmilk with its complex mix of living microbes. And soon this may be seen as the ideal probiotic mixture for all ages, essential to saving lives. For superbugs are no longer responding to the last line antibiotic. A final reminder of the importance of breastmilk is detailed on p. 174-5 of Milk matters: “As mentioned earlier, recent research has found that the breastmilk-derived complex called HAMLET – human α-lactalbumin made lethal to tumour cells – kills cancer cells while stimulating an innate immune response in surrounding healthy tissue. HAMLET can also cause bacteria like Multiply Resistant Staphylococcus aureus (golden staph, MRSA) to become once again sensitive to antibiotics.” Soon adults may be competing with babies for access to banked human milk!
But read Milk Matters: it has more about all this. And let me know what you think. Another more expensive textbook (twice the price, half the size of Milk Matters) is Wahn and Sampson (eds) Allergy Immunity and Tolerance in Early Childhood (Academic Press/Elsevier 2016). This contains much that is relevant for the scientifically minded, although as usual breastfeeding and infant formula are discussed inadequately.