title: Super-efficient starch absorption. A risk factor for colonic neoplasia?
abstract: We tested the hypothesis that super-efficient starch absorption, by reducing the supply of carbohydrate to the colon, may be associated with and possibly promote colonic neoplasia. By means of breath hydrogen measurements following a potato meal and comparison with the hydrogen response to lactulose, the amount of starch escaping small bowel absorption was measured in 10 patients who had a colonic adenoma removed endoscopically and in 10 controls. The subjects' consumption of starch and fiber was assessed. Percentage unabsorbed starch was approximately half as much in the patients (5.3%) compared with the controls (10.9%, P less than 0.05). Consumption of starch and dietary fiber, and mouth-to-cecum transit times were not significantly different. Unabsorbed starch was calculated to contribute to 6.0 g/day colonic carbohydrate in the patients and 10.9 g/day in the controls (P less than 0.05). This study confirms that unabsorbed starch provides an important quantity of colonic carbohydrate and suggests that super-efficient starch absorption, by reducing this provision, may promote colonic neoplasia.
authors.affiliation: Department of Medicine, St. James's University Hospital, Leeds, England.
authors.forename: J R
authors.initials: JR
authors.lastname: Thornton
authors.forename: A
authors.initials: A
authors.lastname: Dryden
authors.forename: J
authors.initials: J
authors.lastname: Kelleher
authors.forename: M S
authors.initials: MS
authors.lastname: Losowsky
mesh_terms: D001944:Breath Tests; D003111:Colonic Polyps / Q000378:metabolism*; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004043:Dietary Fiber / Q000008:administration & dosage; D005260:Female; D005772:Gastrointestinal Transit; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007408:Intestinal Absorption; D007792:Lactulose / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D011198:Solanum tuberosum; D013213:Starch / Q000378:metabolism*
chemical_list: D004040:Dietary Carbohydrates; D004043:Dietary Fiber; D007792:Lactulose; D006859:Hydrogen; D013213:Starch