Gut microbiota / gut microbiome
DEDarmmikrobiota / Darmmikrobiom
Your gut microbiota is the community of roughly 38 trillion bacteria (plus archaea, fungi, and viruses) living in your gut, densest in the colon. Together they carry a gene catalog about 150 times bigger than your own genome. And they do jobs you cannot do alone. They ferment dietary fiber into short-chain fatty acids. They make some B vitamins and vitamin K2. They reshape your bile acids. And they fine-tune your gut immunity. The makeup varies hugely from person to person, shaped by birth mode, infant feeding, diet, geography, antibiotics, and age. Those differences make it hard to define one 'optimal' composition. Technically, 'microbiome' means both the organisms and their genes, while 'microbiota' means the organisms. But in practice, people use the two words interchangeably.
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