title: Effect of resistant starch on fecal bulk and fermentation-dependent events in humans.
abstract: This study investigated the effect of two diets, which differed in resistant starch (RS) concentration, on fecal bulk and fermentation-dependent events in 11 humans. Amounts of RS consumed were 5.0 +/- 0.4 and 39.0 +/- 3.0 g/d (mean +/- SEM) for the low- and high-RS diets, respectively. The two diets were fed for 3 wk each in a randomized crossover design. Fecal collections were made in the third week of each study period. The high-RS diet produced an increase (P < 0.01) in total fecal output (from 138 +/- 22 to 197 +/- 37 g/d) and lowered fecal pH (6.9 +/- 0.1 to 6.3 +/- 0.1). There were significant increases (P < 0.05) in the fecal concentrations and daily excretion of butyrate (+38% and +100%, respectively) and acetate (+26% and +72%, respectively) during the high-RS period. The fecal excretion (g/d) of nonstarch polysaccharides (NSP) also rose by 50% during the high-RS diet, suggesting that the presence of starch in the colon may affect the fermentation of NSP. Subjects reported an increase in flatulence and easier defecation. These results demonstrate that RS has a significant impact on putative markers of colonic health in humans.
authors.affiliation: School of Nutrition and Public Health, Deakin University, Malvern, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Phillips
authors.forename: J G
authors.initials: JG
authors.lastname: Muir
authors.forename: A
authors.initials: A
authors.lastname: Birkett
authors.forename: Z X
authors.initials: ZX
authors.lastname: Lu
authors.forename: G P
authors.initials: GP
authors.lastname: Jones
authors.forename: K
authors.initials: K
authors.lastname: O'Dea
authors.forename: G P
authors.initials: GP
authors.lastname: Young
mesh_terms: D000085:Acetates / Q000032:analysis; D000328:Adult; D002087:Butyrates / Q000032:analysis; D003106:Colon / Q000378:metabolism / Q000502:physiology; D018592:Cross-Over Studies; D003672:Defecation / Q000187:drug effects* / Q000502:physiology; D004040:Dietary Carbohydrates / Q000032:analysis / Q000494:pharmacology*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005243:Feces / Q000737:chemistry*; D005260:Female; D005285:Fermentation / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000032:analysis; D008297:Male; D008875:Middle Aged; D011134:Polysaccharides / Q000032:analysis; D013213:Starch / Q000032:analysis / Q000494:pharmacology*; D011795:Surveys and Questionnaires
chemical_list: D000085:Acetates; D002087:Butyrates; D004040:Dietary Carbohydrates; D005232:Fatty Acids, Volatile; D007773:Lactates; D011134:Polysaccharides; D013213:Starch