Read condition-specific symptoms and clinical context for Faecalibacterium prausnitzii. One of the most abundant gut bacteria in healthy adults, and a major supplier of butyrate to the colon.
F. prausnitzii is among the most abundant bacteria in the healthy adult gut, reported at 5 to 15% of the total bacterial population, and it is an important supplier of butyrate to the colonic lining. It is strictly anaerobic and extremely oxygen-sensitive: published work notes that faecalibacteria cannot withstand even a few minutes of exposure to ambient air, which makes the species difficult to culture and to study. Lower abundance has been observed alongside inflammatory bowel disease, colorectal cancer and type 2 diabetes, but those are associations reported in studies rather than demonstrated causes or treatments. Older studies used a broader species grouping: strain A2-165 is now classified as F. duncaniae. Historical abundance and association findings may include relatives separated by newer taxonomy.
This profile describes a normal and abundant member of the healthy human colon, not an infection. No symptoms are listed because the bundled evidence describes it as a beneficial-associated resident and butyrate producer, and none are invented here. Studies report lower abundance alongside inflammatory bowel disease, colorectal cancer and type 2 diabetes; those are associations with conditions that have many causes, not symptoms caused by this bacterium.
Source check: 2026-09-19. Educational content; independent scientific review remains pending.