Microbial diversity in human gut affected by grape polyphenols

The goal is to assess the impact of supplementation with proanthocyanidin-rich grape polyphenol (GP) extract on the human gut flora composition. Subjects first were supplemented with 20 g of soy protein isolate (SPI) 2x/day for 5 days as a wash-out period. After a gap day, subjects were instructed to take 20 g of a soy protein isolate (SPI) complexed to GP, containing 1 g of GP, twice a day for 10 days. Subjects were directed to consume a diet low in proanthocyanidins during the study duration.