The terms gut flora and intestinal flora are old terms. The term 'flora' technically refers to any species belonging to the plant kingdom.
The organisms that colonize the human body are certainly not plants; they are bacteria, yeasts, fungi, viruses, archaea and other microorganisms. Their habitation within and their introduction to your body has a profound influence on your future health, initiated long before you are born.
Your microbiome comprises as much as 3% of your body mass. Primarily, microbes reside in the gut; however, no surface of the human body is free of them.
Many of these organisms are symbionts; they live within other organisms, such as us! In the majority of cases, this symbiotic living arrangement benefits both the microbes and their host.
Some members of the microbiota are pathogenic (disease-causing). Their populations are smaller and unable to cause disease until the surrounding environment changes to favor their growth.
Microbiome research is taking place worldwide, aiming to understand the role of the microbiota in human health. Here is what the current body of research has uncovered.
Modern medical science wants answers to these questions:
Everything you touch and eat introduces microbes to your body, every day. It appears that the most diverse microbial communities are located in the oral cavity and the gut. We can postulate this is due to their role in eating, as no other sites come into contact with literally thousands of microbial samples (foods) in quite the same way as your mouth and digestive tract. The Hologenome Theory of Evolution questions that natural selection is not merely based on an individual organism, but the organism together with its attendant microbial populations.
Diversity can be influenced by the following factors:
Written by Annalies Corse BMedSc, BHSc.
References
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