May 6/Food & Farm Week -- "Certain dietary fibers have been shown to reduce the incidence of colon tumors in rats fed high-fat diets. Although insoluble fibers are most commonly associated with this anticancer potential, certain soluble fibers, Such as psyllium, flaxseed and soybean, have also been shown to inhibit chemically induced colon cancer in rodents," scientists writing in the journal Cereal Foods World report.
"The main purpose of this research was to evaluate the effect of wheat bran, flaxseed and soybean alone and in combination on azoxymethane-induced colon tumorigenesis in Fisher-344 rats maintained on high-fat diets. A total of 165 male Fisher-344 rats was divided into 11 test diet groups. After three weeks on test diets, the rats were given injections of ethane AOM (15mg/kg of body weight) and remained on their respective experimental diets until killed by exsanguination under anesthesia at week 10. The colons were removed and prepared for evaluation of colonic aberrant crypt formations (ACF). Results indicate that both insoluble (wheat bran) in various combinations with soluble (soy, flax) fibers significantly reduced both the number and size of ACE. The soybean diet resulted in a significant decrease (p<0.05) in the number of ACF compared with wheat bran or flax," wrote C.L. Nochera and colleagues, Grand Valley State University.