Resistant Starch May Reduce Colon Cancer Risk From Red Meat

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A diet high in red meat increases risk of colon cancer. But eating resistant starch—a carbohydrate that acts like fiber—may reduce that risk, according to a study in August’s Cancer Prevention Research.

“Red meat and resistant starch have opposite effects on the colorectal cancer–promoting microRNAs,” said first author Karen Humphreys, Ph.D., a research associate at the Flinders Centre for Innovation in Cancer at Australia’s Flinders University. “This finding supports consumption of resistant starch as a means of reducing the risk.”

In a 2011 study, colon cancer risk increased by 29% for every 100g of red or processed meat eaten per day, plateauing around 140g. But no one knew exactly why.

This new study offers insights, said Sonia Kupfer, M.D., director of the Gastrointestinal Cancer Risk and Prevention Clinic at the University of Chicago Medical Center. “It may be that protective factors and risk factors work through the same pathways.” She noted other possible mechanisms: “Heme iron and heterocyclic amines from red meat cooked at high temperature alter gene expression and increase proliferation. Butyrate from microbes decreases proliferation. This paper starts to provide intriguing ways in which we can think about these dietary factors mechanistically altering the colonic epithelium. But there might be other effects as well,” she said. “Dietary substances can be complex.”