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So far, it’s always been about genes. And most likely you have been considering only the cells of your body and their genes. However, you may have heard that there are microbes in and on us. This refers primarily to bacteria, viruses, and fungi, which in their entirety are referred to as our microbiome. “But it can’t be that important”, you might think to yourself, right? The amazing thing is that you as an adult consist of about 30 trillion cells, the number of all your bacteria in you (lungs, intestine) and on you (skin) is about 38 trillion, which is about 1.3 times as many as your own body has cells. These bacteria are not just one strain but different ones and thus all genetically different. This multiplies to a total of 3.3 million bacterial genes, which is 150 times the amount of our own human genes. Moreover 142,809 different viruses (so-called bacteriophages) that infect our gut bacteria have been identified which further increase our microbial complexity. So genetically you are clearly outnumbered by your microbiome. You could view this as if we live in a symbiosis with our microbiome. Our microbiome influences us and we our microbiome, positively or negatively, respectively. So, whenever you think about yourself, you should also consider that half of you are your bacteria, viruses, and fungi. These are not unhygienic contamination, as some people think and exaggerate especially in skin hygiene or carelessly take antibiotics, but we live in a symbiosis. We need each other. Most of the microbiota is found in the intestine. This means that after a bowel movement we might be—for a short moment—in the majority with our cells, but otherwise it is probably more of a draw. But let’s start with the skin.

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Schmidt, H.H.H.W. (2022). Outnumbered. In: The end of medicine as we know it - and why your health has a future. Springer, Cham.

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