Fruit consumption as a gut health improving strategy to lower arsenic exposure risk from rice consumption

Inorganic arsenic (As) is widely detected in rice. Reducing As intestinal absorption (i.e., As oral bioavailability) can protect humans from As exposure. Although studies have shown reduced As bioavailability with probiotics or prebiotics due to enhanced As methylation in the gut or strengthened intestinal barriers triggered by gut microbiota improvement, the role of fiber-rich natural foods in everyday diets in mitigating rice As bioavailability via improving gut health has not been assessed. Using mouse models, this study investigates whether and how fruit consumption reduces As bioavailability from rice containing 0.17-0.28 μg As/g. Compared to the exposure control group, mice consuming As-containing rice alongside six common fruits (guava, apple, kiwifruit, banana, grape, and pitaya, 16% in rice on a dry weight basis) experienced significant reductions in As accumulation in tissues and urinary As excretion, and increased fecal As elimination, suggesting reduced As bioavailability. The effects were attributed to the stimulation of gut beneficial bacteria that produced short-chain fatty acids, which initiated a cascade of downstream outcomes, including reduced intestinal inflammation, strengthened intestinal barriers, enhanced intestinal motility, increased fecal output, and improved As methylation within the gut. These processes limited As paracellular transport, shortened its retention time in the gut, and transformed highly bioavailable inorganic As into less bioavailable methylated As species, collectively leading to reduced As bioavailability. These findings highlight fruit consumption as a gut health-improving strategy to reduce As bioavailability, which may protect humans from As toxicity.