title: Investigation of normal flatus production in healthy volunteers.
abstract: Flatulence can cause discomfort and distress but there are few published data of normal patterns and volumes. Twenty four hour collections were made using a rectal catheter in 10 normal volunteers taking their normal diet plus 200 g baked beans. Total daily volume ranged from 476 to 1491 ml (median 705 ml). Women and men (both n = 5) expelled equivalent amounts. The median daily flatus hydrogen volume was 361 ml/24 h (range 42-1060) and the carbon dioxide volume 68 ml/24 h (range 25-116), three volunteers produced methane (3, 26, and 120 ml/24 h), and the remaining unidentified gas (presumably nitrogen) or gases contributed a median 213 ml/24 h (range 61-476). Larger volumes of flatus were produced after meals than at other times. Flatus produced at a faster rate tended to contain more fermentation gases. Flatus was produced during the sleeping period, but the rate was significantly lower than the daytime rate (median 16 and 34 ml/h respectively). Ingestion of a 'fibre free' diet (Fortisip) for 48 hours significantly reduced the total volume collected in 24 hours (median 214 ml/24 h), reduced the carbon dioxide volume (median 6 ml/24 h), and practically eradicated hydrogen production. The volume of unidentified gas was not significantly affected (median 207 ml/24 h). Thus fermentation gases make the highest contribution to normal flatus volume. A 'fibre free' diet eliminates these without changing residual gas release of around 200 ml/24 h.
authors.affiliation: Sub-department of Human Gastrointestinal Physiology and Nutrition, Royal Hallamshire Hospital, Sheffield.
authors.forename: J
authors.initials: J
authors.lastname: Tomlin
authors.forename: C
authors.initials: C
authors.lastname: Lowis
authors.forename: N W
authors.initials: NW
authors.lastname: Read
mesh_terms: D000328:Adult; D002245:Carbon Dioxide; D002940:Circadian Rhythm; D004043:Dietary Fiber; D005260:Female; D005740:Gases / Q000032:analysis; D006801:Humans; D006859:Hydrogen; D007422:Intestines / Q000502:physiology*; D008297:Male; D008697:Methane; D012890:Sleep; D013997:Time Factors
chemical_list: D004043:Dietary Fiber; D005740:Gases; D002245:Carbon Dioxide; D006859:Hydrogen; D008697:Methane