Processed dietary fiber partially hydrolyzed guar gum increases susceptibility to colitis and colon tumorigenesis in mice.

The vital role of naturally occurring dietary fibers (DFs) in maintaining intestinal health has fueled the incorporation of refined DFs into processed foods. The present study assessed the impact of purified DF partially hydrolyzed guar gum (Phgg) on intestinal inflammation and colitis-associated colon carcinogenesis (CAC). Surprisingly, wild-type mice fed Phgg exhibited more severe dextran sulfate sodium (DSS)-induced colitis than the control group. Additionally, Phgg feeding led to increased colonic expression of genes promoting cell proliferation. Accordingly, extensive colon tumorigenesis was observed in Phgg-fed mice in the azoxymethane (AOM)/DSS model, whereas the control group exhibited no visible tumors. Mice fed low-Phgg (2.5%) diet exhibited more colitis and tumorigenesis than controls, but less than those on regular Phgg diet (7.5%), suggesting a dose-dependent influence of Phgg on colitis and CAC development. Our study reveals that Phgg supplementation exacerbates colitis and promotes colon tumorigenesis, warranting further investigation into the potential gastrointestinal health risks associated with processed Phgg consumption.