Prebiotics are foods that alter the microbiome. They are important to many potential microbiome therapeutics because they could be used to shift the microbiome from a dysbiotic, or unhealthy state, to a normal healthy state. Most scientists that study prebiotics investigate indigestible fiber, because these are known to survive digestion are broken down by specific microbes, thus predictably selecting for specific organisms’ growth. Recently though, other prebiotics are being studied. A major class of these are polyphenolic compounds, which provide the antioxidant characteristics of plant material. Last week researchers from Spain studied the shift in the microbiome that may be induced by red wine and coffee in particular. They published their results in the journal Food & Function.

The researchers studied 23 patients that had allergic rhinosinusitis or asthma as well as 22 age-matched controls. They chose individuals with autoimmune diseases because of the promise of prebiotics affecting their diseases. They asked all of the individuals to fill out a food survey of what they had eaten in the past year, and how often they ate it. After, the scientists took samples of their feces and measured the bacteria within it. The scientists found that the abundance of Clostridium, Lactococcus and Lactobacillus was directly associated with polyphenol intake from coffee, and that Bacteroides was positively associated with red wine consumption. Unfortunately, they noted that these did not differ between allergic people and healthy ones.

This study was certainly lacking in its scope and rigor. It did not attempt any interventional studies to controllably reproduce these effects, and it did not identifiy specific polyphenols that are responsible. Nonetheless, it does begin to define how alternative prebiotics may affect our microbiome. Polyphenols in particular are linked to all sorts of health benefits, normally attributed to their anti-oxidation, however perhaps they positively impact the microbiome as well.