Berries in Microbiome-Mediated Gastrointestinal, Metabolic, and Immune Health

Purpose of Review Current research has shown that berry-derived polymeric substrates that resist human digestion (dietary fibers and polyphenols) are extensively metabolized in the gastrointestinal tract dominated by microbiota. This review assesses current epidemiological, experimental, and clinical evidence of how berry (strawberry, blueberry, raspberry, blackberry, cranberry, black currant, and grapes) phytochemicals interact with the microbiome and shape health or metabolic risk factor outcomes. Recent Findings There is a growing evidence that the compositional differences among complex carbohydrate fractions and classes of polyphenols define reversible shifts in microbial populations and human metabolome to promote gastrointestinal health. Interventions to prevent gastrointestinal inflammation and improve metabolic outcomes may be achieved with selection of berries that provide distinct polysaccharide substrates for selective multiplication of beneficial microbiota or oligomeric decoys for binding and elimination of the pathogens, as well as phenolic substrates that hold potential to modulate gastrointestinal mucins, reduce luminal oxygen, and release small phenolic metabolites signatures capable of ameliorating inflammatory and metabolic perturbations. Summary These mechanisms may explain many of the differences in microbiota and host gastrointestinal responses associated with increased consumption of berries, and highlight potential opportunities to intentionally shift gut microbiome profiles or to modulate risk factors associated with better nutrition and health outcomes.