A plant-centred diet feeds microbial diversity with its abundant fibre, but true balance also requires attention to vitamin B12 and thoughtful planning.
Altitude hypoxia lowers gut oxygen, so within 48–72 hours obligate anaerobes such as Faecalibacterium decline — a shift that may underlie the digestive complaints of altitude.
Traditional, minimally processed, fiber-rich diets sustain a diverse microbiota shaped over millennia, which a Western diet can narrow within a single generation.