Effect of food components on arsenic metabolism by the gut microbiota using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME).

The toxicity of environmental arsenic (As) exposure can be modulated by the gut microbiota via As reduction, methylation, and thiolation reactions. However, the precise role of food components in these metabolic processes remain unclear. This study systematically explored the impacts of 24 representative food components on As metabolism by human gut microbiota. Based on the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) model, As bioaccumulation, As speciation profiles, gut microbiota composition, and short-chain fatty acids were quantified to assess their interactions. Of the 24 food components, 15 demonstrated alterations in As metabolism by the gut microbiota. Soy protein, vitamin B12, and erythritol increased methyl arsenic by 8.80-85.40%, while butyric acid (a key energy metabolite) rose 7.78- and 17.13-fold with erythritol or soy protein. The relative abundance of Sporanaerobacter, Stenotrophomonas, and Pseudomonas demonstrated strong positive correlations with As methylation (r = 0.917, 0.770, and 0.679, respectively, p < 0.0001). This study highlights how food components influence As metabolism to inform both personalized nutrition strategies and As exposure risk assessment.