Although intestinal microflora contributes to human health, there is little known about the effects of diet on the composition of this microflora.
In this study, researchers from the Netherlands and the United States assessed changes in fecal microflora composition and fecal bile acid profile in volunteers.
This was part of a crossover feeding study which investigated the effects of black tea drinking on blood lipids in hypercholesterolemic volunteers.
The team analyzed fecal microflora composition using fluorescent in-situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE).
|Each individual harbors a specific bacterial profile that changes little.|
|Journal of Nutrition|
The team found, using DGGE analysis, that each individual has a specific bacterial profile that exhibits little change over time. They determined that changing from a free living diet to the study diet or to black tea drinking did not significantly change these profiles.
However, using FISH analysis the researchers found that black tea decreased the amounts of bacteria that were detected by the universal bacterial probe.
The team did not identify and effects of either diet or black tea drinking on the levels and proportions of fecal bile acids.
Dr Volker Mai's team concluded, "Our results indicate that tea drinking affects some microflora components".
"Larger studies with well defined end points that control for the observed variation are needed to improve our understanding of the effects of diet on intestinal microflora and fecal bile acid profile".