Our gut is home to trillions of bacteria, numbering more than the cells in the rest of our body, and these bacteria help us to digest our food, absorb nutrients and strengthen our immune system. This complex bacterial ecosystem, called the gut microbiota, also helps to prevent bad bacteria from colonising our bodies and making us ill.
As part of the symbiotic relationship between the gut microbiota and our bodies, the bacteria derive nutrition from our food and convert it into compounds that we can't make ourselves. Some of these compounds are part of the arsenal that combats harmful bacteria. To date, these extracellular products are the only identified defense mechanisms associated with gut.
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