Dietary soluble fibers are fermented by gut bacteria into short-chain fatty acids (SCFA),
which are considered broadly health-promoting. Accordingly, consumption of such fibers
ameliorates metabolic syndrome. However, incorporating soluble fiber inulin, but not
insoluble fiber, into a compositionally defined diet, induced icteric hepatocellular carcinoma
(HCC). Such HCC was microbiota-dependent and observed in multiple strains of dysbiotic
mice but not in germ-free nor antibiotics-treated mice. Furthermore, consumption of an inulin …

In this article, Singh et al. have shown that feeding innate immune-deficient mice a diet
enriched in soluble fibers (including inulin, pectin, and fructo-oligosaccharides) but not
insoluble fibers could induce liver cancer (Figure 1)(Singh et al., 2018). Fiber-induced liver
cancer did not occur in WT mice, however, WT mice fed a high-fat diet (HFD) could be
susceptible to liver cancer upon consumption of soluble fibers. These induced cancers are
initiated with cholestasis, followed by hepatocyte death and neutrophilic inflammation in the …