Dietary emulsifiers alter composition and activity of the human gut microbiota in vitro

Dietary additives are widely used in processed food products and have become a target for research in terms of their impact on the gut microbiome. Recent studies with dietary emulsifiers in both in vitro and murine models have indicated a strong impact on the gut microbiome and host health, possibly related to chronic gut inflammation and other western diseases. However, not many emulsifiers have been studied up to this point. A detailed overview of the effects of dietary emulsifiers on the human gut microbiota and an assessment of inter-individual differences in response remain elusive as well.This study aimed at delving deeper into the effects of 5 dietary emulsifiers on the composition and the activity of the gut bacteria. Five dietary emulsifiers in 3 concentrations were incubated with fecal material from 10 human donors for 48 hours, after which the community structure and functionality were assessed in detail. We show that dietary emulsifiers severely impact the gut microbiota proportional to their emulsifying strength and alter it towards a more pro-inflammatory community.