Effects of consumption of white bread and brown bread on the concentrations of fecal bile acids and neutral steroids and on fecal enzyme activities

Abstract

The effects of consumption of white bread (low fiber) and brown bread (high fiber) on the fecal excretions of bile acids and neutral steroids and on fecal enzyme activities were assessed in ten healthy males (mean age 27 years). The study subjects included in their normal diet for one-week period in turn, white bread and brown bread (230–320 g/d). Fecal samples were collected at the two final consecutive days of each study week period. The daily fecal output was significantly higher, the concentration of cholic acid in feces significantly decreased by approx. 29% and a tendency for lower concentrations of other bile acids and neutral steroids occurred during consumption of brown bread compared to those during consumption of white bread. Also, the fecal enzyme activities of β-glucosidase and β-glucuronidase significantly decreased during the same period, while those of urease and tryptophanase remained unchanged. The lower concentration of cholic acid and decreased enzyme activities of β-glucosidase and β-glucuronidase are indications of positive effects of consumption of brown bread.