Berries-Gut Microbiota Interaction and Impact on Human Health: A Systematic Review of Randomized Controlled Trials

Berries represent an important source of bioactive compounds, among which, (poly)phenols are the main constituents. (Poly)phenols have been shown to have important biological activities and in particular, to take a relevant role in mediating the modulation of gut microbiota and human health. Gut microbiota constitute significant players in the metabolism of ingested (poly)phenols and consequently in their biological effects. However, the evidence regarding the mutual contribution between (poly)phenol intake and gut microbiota activity in humans is still unclear. The aim of the current systematic review was to collect and assess results from randomized clinical trials addressing the role of berries in the modulation of the gut microbiota composition and how this can contribute to the metabolism of berry (poly)phenols. When information was available, the interaction of berry-gut microbiota on human health was evaluated. A total of 16 trials were included and analyzed. Overall, berries and their (poly)phenols could represent a driver for the modulation of intestinal microbes. The gut microbiota catabolize (poly)phenols by producing bioactive metabolites which can positively affect both the composition of commensal microbiota and also the host health.