Dietary fiber in the Japanese diet as investigated in connection with colon cancer risk.

The low risk of colon cancer among the Japanese suggests a high intake of dietary fiber. Composite diets for 1959, 1970, and 1979 were prepared using food consumption data from the National Nutrition Survey in Japan and analyzed for non-starch polysaccharides (NSP) at the Dunn Clinical Nutrition Centre in Cambridge. The results showed that average intake of NSP by Japanese in the above years did not exceed 13 g per day, which is as low as the corresponding intake by the Scandinavians and the British, whose risk of colon cancer is known to be high.