Breast really is best
Microbiomes are the beneficial microbial communities associated with plants and animals. We all have them and they influence everything about their host from development and fitness to reproduction. Needless to say, microbes are a huge driving force in the evolution of higher organisms.
The microbiome that most concerns humans is the one in our guts, and which primes our immune systems, helps us digest our food and protects us against infection. We acquire some of our ‘good bacteria’ from our mums when we pass through the birth canal but many of the bacteria found in our guts are obligate anaerobes which are killed by exposure to air. So how do they get from mother and child?
Recently it has been suggested that bacteria may actually migrate from the mothers gut to the mammary glands and be transmitted directly to babies through her breast milk. A paper just published in Environmental Microbiology provides the first direct evidence for this ‘mother-neonate direct transfer’ model.
The authors used culture dependent and independent methods to examine the microbes present in the faeces (poo to you) of mums and their newborn babies (neonates) and in the mum’s breast milk. They found the same species in all three samples for mother-baby pairs and the highest evidence for direct transfer was for strains of bifidobacteria, the Y shaped “good bacteria” that are added to probiotic drinks and yoghurts.
Although this study was carried out in collaboration with Nestle (who have a big line in probiotics) it is backed up by other recent studies and it certainly makes a lot of sense. Exactly how the bacteria get from the mother’s gut to the breast milk remains mysterious but expect rapid progress to be made in figuring this out. And remember, breast really is best.