Bifidobacterium animalis strain DN-173 010 shortens the colonic transit time in healthy women: a double-blind, randomized, controlled study

Background: A previous study has suggested that Bifidobacterium animalis DN-173 010 shortens the colonic transit time in women. Aim: To confirm this effect and to determine whether modifications of the faecal bacterial mass and/or faecal secondary bile salts may be the explanation. Methods: A double-blind, cross-over study was performed. Thirty-six healthy women were studied in four consecutive 10-day periods. During periods 2 and 4, they ingested three 125 g cups per day of a fermented milk which was either a product containing B. animalis DN-173 010 or a control without bifidobacteria. Periods 1 and 3 were run-in and washout periods, respectively. The total and segmental colonic transit times were assessed using a pellet method. In 12 subjects, all stools were collected and analysed for pH, faecal weight. bacterial mass and bile acids. Results: The total and sigmoid transit times were significantly shorter during dosing with B. animalis compared to the control period. The other transit times, faecal weight, pH. bacterial mass and bile acids were not significantly affected. Conclusions: B. animalis DN-173 010 shortens the colonic transit time in healthy women. This effect is not explained by modifications or the faecal bacterial mass or secondary bile acids.