Studies have suggested a role of black raspberries, by way of the polyphenolic compounds they contain, in reducing the risk of a variety of cancers. Wancai Yang, from the University of Illinois at Chicago (Illinois, USA), and colleagues examined the potential activity of black raspberries in the colorectal tract of two mouse models of colorectal cancer. The first strain – Apc1638 – is engineered to develop intestinal tumors, whereas the second strain – Muc2 – induces colitis, an  inflammation of the large intestine that is suspected to contribute to the development of colorectal cancer.  Both sets of mice ate a Western-style diet, high in fat and low in vitamin D and calcium, or the same diet with an additional 10% freeze-dried black raspberry powder.  After 12 weeks, the researchers found that Apc1638 mice that ate the additional raspberries displayed a 45% reduction in tumor incidence and a 60% reduction in the number of tumors. As well, the Muc2 mice fed the additional raspberries showed a reduction in chronic inflammation, with a 50% reduction in both tumor incidence and the number of tumors.  The team concludes that: “Collectively, our data suggest that [black raspberries] are highly effective in preventing intestinal tumor development … through targeting multiple signaling pathways.”