title: Dietary supplementation with rice bran or navy bean alters gut bacterial metabolism in colorectal cancer survivors.
abstract: Heat-stabilized rice bran (SRB) and cooked navy bean powder (NBP) contain a variety of phytochemicals that are fermented by colonic microbiota and may influence intestinal health. Dietary interventions with these foods should be explored for modulating colorectal cancer risk.
  
  
  
  A randomized-controlled pilot clinical trial investigated the effects of eating SRB (30 g/day) or cooked navy bean powder (35 g/day) on gut microbiota and metabolites (NCT01929122). Twenty-nine overweight/obese volunteers with a prior history of colorectal cancer consumed a study-provided meal and snack daily for 28 days. Volunteers receiving SRB or NBP showed increased gut bacterial diversity and altered gut microbial composition at 28 days compared to baseline. Supplementation with SRB or NBP increased total dietary fiber intake similarly, yet only rice bran intake led to a decreased Firmicutes:Bacteroidetes ratio and increased SCFA (propionate and acetate) in stool after 14 days but not at 28 days.
  
  
  
  These findings support modulation of gut microbiota and fermentation byproducts by SRB and suggest that foods with similar ability to increase dietary fiber intake may not have equal effects on gut microbiota and microbial metabolism.
authors.affiliation: Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO, USA.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Sheflin
authors.affiliation: Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
authors.forename: Erica C
authors.initials: EC
authors.lastname: Borresen
authors.affiliation: Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, USA.
authors.forename: Jay S
authors.initials: JS
authors.lastname: Kirkwood
authors.affiliation: Department of Chemistry, Central Instrument Facility, Colorado State University, Fort Collins, CO, USA.
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Boot
authors.affiliation: Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO, USA.
authors.forename: Alyssa K
authors.initials: AK
authors.lastname: Whitney
authors.affiliation: Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO, USA.
authors.forename: Shen
authors.initials: S
authors.lastname: Lu
authors.affiliation: Department of Medicine, Division of Medical Oncology, University of Colorado Denver and Lone Tree Oncology affiliation of University of Colorado Cancer Center, Aurora, Colorado, USA.
authors.forename: Regina J
authors.initials: RJ
authors.lastname: Brown
authors.affiliation: Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, USA.
authors.forename: Corey D
authors.initials: CD
authors.lastname: Broeckling
authors.affiliation: Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
authors.forename: Elizabeth P
authors.initials: EP
authors.lastname: Ryan
authors.affiliation: Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO, USA.
authors.forename: Tiffany L
authors.initials: TL
authors.lastname: Weir
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000382:microbiology*; D019587:Dietary Supplements; D005243:Feces / Q000382:microbiology; D005260:Female; D000069196:Gastrointestinal Microbiome / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012275:Oryza; D017741:Survivors
keywords: Bile acids; Heat-stabilized rice bran; Navy bean; Short chain fatty acids; Stool microbiota