In recent years, there has been an explosion of research describing the role of the human microbiota and its influence on health and disease. While we still have much to learn, there is nevertheless, wide epidemiological and experimental evidence to support the notion that the microbial community of the infant gut plays a profound role in programming and directing immune development. Although there is extensive variability across individuals, the healthy human microbiome is always a diverse ecology that develops under a process of species succession, from infancy to adulthood. In this sense, the human microbiome can be compared to other complex ecologies in which the stability and health of the system is determined by the variety and number of microbial species and their relationship to each other and the host environment. We now know that a loss of microbial diversity in infancy can be a key driver in the development of numerous chronic diseases in later life.
There is also growing evidence for the use of probiotics in the management of specific immune related conditions. While the tendency of late has been to focus on the treatment of specific conditions with particular strains of bacteria, we must remember that it is this principle of ecological diversity that will ultimately contribute to homeostasis. This is achieved through key environmental and dietary factors; the earlier in life the better.
Among breastfed infants, bifidobacterium-dominated microbiotas are more frequent than among infants fed with formula, but other compositions are also common. After then, a large shift in microbiota composition accompanies the introduction of solid foods into the diet. A diet rich in vegetables and water soluble fibre will foster a very different bacterial community compared to a diet high in animal protein and simple sugars.
In this infographic we explore the intimate relationship between the developing microbiota of the infant gut and immune health and maturation.
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