See http://www.westonaprice.org/health-topics/food-in-china-variety-and-monotony/ http://www.westonaprice.org/health-topics/food-in-china-vari... - it discuss

See http://www.westonaprice.org/health-topics/food-in-china-variety-and-monotony/ http://www.westonaprice.org/health-topics/food-in-china-vari... - it discuss results of studies in China from 1980-1990 that showed that regions in China where people consumed pretty much all calories from rice or vegetables or those where people do eat a lot of meat have similar cancer rates making highly problematic any claim that excessive carbo is associated with increased cancer risk.