A healthy gut contains bacteria and immune cells that ward off infectious agents, such as bacteria, viruses and fungi.
There are 300 to 500 different kinds of bacteria containing nearly two million genes residing inside the gut. When paired with other organisms, they form what is known as the microbiome.
Researchers studying the response of the gut to probiotics warned of prolonged microbiome disturbances, which could be linked to allergies, inflammation, and obesity.
Immunologist Eran Elinav of the Weizmann Institute of Science in Israel, and colleagues sampled the microbiomes of healthy volunteers using endoscopies and colonoscopies.
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