Fiber May Bind Colon Carcinogens
Fiber may bind colon carcinogens
High-fiber diets have been associated with a reduced risk of human colon cancer. Possible explanations include: that fiber's bulk makes it less likely that carcinogens passing through the digestive tract will touch the colon's surface; that, by accelerating food's passage through the digestive tract, fiber reduces a carcinogen's time in contact with the colon's walls; and that fiber may bind to the carcinogens, pulling them out of the body before they can do harm. New research by food chemists at the University of Lund in Sweden offers further support for this last hypothesis.
The researchers used three chemicals known to produce tumors in the intestinal tract of laboratory animals. These heterocyclic amines--members of the quinoline family--form during the cooking of meats at high temperatures. In test tube environments meant to roughly simulate conditions that might occur during digestion, each was mixed with one of 13 different food fibers, including whole rye flour, whole barley flour, oat bran and wheat bran, among others. …