{"entity":{"id":"gut-microbiome-diversity","kind":"term","name":"Gut microbiome diversity and composition","aka":["Alpha diversity","Shannon index","Dysbiosis"],"tldr":"How many different kinds of bacteria live in the gut and which ones dominate. Higher diversity and certain species are linked with better immunotherapy response; antibiotics and poor diet reduce both.","summary":"Alpha diversity (within a person) and specific taxa (Faecalibacterium, Ruminococcaceae, Akkermansia muciniphila, Bifidobacterium) associate with checkpoint-inhibitor response, though the taxa differ between cohorts and countries, and no microbiome test is validated for clinical use. Diet (fibre), antibiotics, proton-pump inhibitors and probiotics are the main modifiable determinants. Causality is supported by mouse FMT experiments and by early human FMT trials.","asOf":"2026-09-08","wikipedia":"https://en.wikipedia.org/wiki/Gut_microbiota","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Gut_microbiota"}],"tags":[],"related":[],"cancers":[],"sections":[],"technologies":["dietary-fibre-microbiome-io","fmt-checkpoint-nonresponders","probiotics-antibiotic-stewardship-io","microbiome-modulation-io"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":["microbiome-tumour"],"terms":["polymorphic-microbiomes"],"trials":[],"people":[],"bottlenecks":["b-immunotherapy-response","b-biomarker-validation"],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Nutrition & lifestyle"},"route":"/terms/gut-microbiome-diversity/","neighbours":{"technology":[{"id":"dietary-fibre-microbiome-io","kind":"technology","name":"Dietary fibre and the gut microbiome for immunotherapy response","route":"/technologies/dietary-fibre-microbiome-io/"},{"id":"fmt-checkpoint-nonresponders","kind":"technology","name":"Faecal microbiota transplantation for PD-1 non-responders","route":"/technologies/fmt-checkpoint-nonresponders/"},{"id":"microbiome-modulation-io","kind":"technology","name":"Microbiome modulation to unlock immunotherapy","route":"/technologies/microbiome-modulation-io/"},{"id":"probiotics-antibiotic-stewardship-io","kind":"technology","name":"Probiotics, antibiotics and stewardship around immunotherapy","route":"/technologies/probiotics-antibiotic-stewardship-io/"}],"pathway":[{"id":"microbiome-tumour","kind":"pathway","name":"Microbiome-tumour interactions","route":"/pathways/microbiome-tumour/"}],"term":[{"id":"polymorphic-microbiomes","kind":"term","name":"Hallmark (2022): polymorphic microbiomes","route":"/terms/polymorphic-microbiomes/"}],"bottleneck":[{"id":"b-biomarker-validation","kind":"bottleneck","name":"Biomarkers are not validated or standardised","route":"/bottlenecks/b-biomarker-validation/"},{"id":"b-immunotherapy-response","kind":"bottleneck","name":"No one can predict who responds to immunotherapy","route":"/bottlenecks/b-immunotherapy-response/"}],"paper":[{"id":"paper-diaz-gay-colibactin-geographic-age-mutational-processes-nature-2025","kind":"paper","name":"Geographic and age variations in mutational processes in colorectal cancer","route":"/key-papers/paper-diaz-gay-colibactin-geographic-age-mutational-processes-nature-2025/"}],"roadmap":[{"id":"colorectal-roadmap","kind":"roadmap","name":"Colorectal cancer roadmap: from the adenoma-carcinoma sequence and the first screening trials to total mesorectal excision, oxaliplatin, RAS testing, immunotherapy for mismatch repair-deficient disease, ctDNA-guided treatment and organ preservation","route":"/roadmaps/colorectal-roadmap/"},{"id":"nutrition-lifestyle-roadmap","kind":"roadmap","name":"Diet, exercise and lifestyle roadmap: causes established → interventions that disappointed → exercise proven as treatment","route":"/roadmaps/nutrition-lifestyle-roadmap/"}],"idea":[{"id":"idea-nl-diet-covariates-io-trials","kind":"idea","name":"Capture diet, fibre and antibiotic exposure in every immunotherapy pivotal trial","route":"/ideas/idea-nl-diet-covariates-io-trials/"},{"id":"idea-nl-upf-controlled-feeding-trial","kind":"idea","name":"Controlled feeding trials to separate ultra-processing from calories","route":"/ideas/idea-nl-upf-controlled-feeding-trial/"},{"id":"idea-crc-early-onset-cause-hunt","kind":"idea","name":"Find out what is driving early-onset bowel cancer, starting with colibactin, before extending screening any further","route":"/ideas/idea-crc-early-onset-cause-hunt/"}],"trial":[{"id":"fmt-pd1-refractory-melanoma-pitt","kind":"trial","name":"FMT plus pembrolizumab in anti-PD-1-refractory melanoma (Pittsburgh)","route":"/trials/fmt-pd1-refractory-melanoma-pitt/"},{"id":"mimic-01","kind":"trial","name":"MIMic-01: healthy-donor FMT plus anti-PD-1, first-line melanoma","route":"/trials/mimic-01/"}]}}