~55 (equivalent to 18 g of bacterial dry matter) %
||Human Homo sapiens
||G. T. Macfarlane and G. R. Gibson, Metabolic Activities of the Normal Colonic Flora, chapter 2 in Human Health: The Contribution of Microorganisms, Edited by S. A. W. Gibson, Springer-Verlag 1994 link , p.18 2nd paragraph
||Stephen AM, Cummings JH (1980) The microbial contribution to human faecal mass. J Med Microbiol 13: 45-56 DOI: 10.1099/00222615-13-1-45PubMed ID7359576
||P.18 2nd paragraph: "The average daily output of material from the colon in the United Kingdom is 120 g (Cummings et al. 1993) and bacteria are a major
component, comprising approximately 55% of faecal solids in persons living on Western diets (primary source), which is equivalent to 18 g of bacterial dry matter, or a total bacterial mass in the gut of 90 g. Their growth and activities are
influenced to a considerable degree by the structure and physiology of the large bowel."