hygiene hypothesis

Recent research has shed light on the crucial “conversation” between gut microbes and infant genes that appear to help the breast-fed infant make a safe transition from life in the womb to life outside. The study was published April 29, 2012, in the open-access journal Genome Biology reports. This confirms earlier findings that show breast-feeding gooses the developing immune system. It elucidated the chemical chatter between genes in the developing infants and their gut bacteria by comparing the bacterial communities and genes found in the guts of breast-fed vs. formula-fed (cow’s milk) 3-month-olds. The researchers studied the gut microbiome information and gene expression levels in the infant gut; they identified genes involved in immunity and defense with altered expression levels in relation to the gut bacteria in breast-fed infants. Breast-fed babies, it emerged, had more diverse gut biota, but their immune systems were ready primed for it. This was almost paradoxical. The babies’ fecal matter had more of the obnoxious, virulent organisms (including resistance to antibiotics and toxic compounds), yet the infant immune system was well primed and ready to shoot! What seems to happen is that killer defence genes are activated in the young immune system by the challenge of meeting hostile pathogens.

Recent research has shed light on the crucial “conversation” between gut microbes and infant genes that appear to help the breast-fed infant make a safe transition from life in the womb to life outside. The study was published April 29, 2012, in the open-access journal Genome Biology reports. This confirms earlier findings that show breast-feeding gooses the developing immune system. It elucidated the chemical chatter between genes in the developing infants and their gut bacteria by comparing the bacterial communities and genes found in the guts of breast-fed vs. formula-fed (cow’s milk) 3-month-olds. The researchers studied the gut microbiome information and gene expression levels in the infant gut; they identified genes involved in immunity and defense with altered expression levels in relation to the gut bacteria in breast-fed infants. Breast-fed babies, it emerged, had more diverse gut biota, but their immune systems were ready primed for it. This was almost paradoxical. The babies’ fecal matter had more of the obnoxious, virulent organisms (including resistance to antibiotics and toxic compounds), yet the infant immune system was well primed and ready to shoot! What seems to happen is that killer defence genes are activated in the young immune system by the challenge of meeting hostile pathogens.