ABSTRACT
A population-based case-control study of the colorectal cancer was conducted in Shanghai (1988-1990). The contributions of diet and nutrients as risk factors of colon cancer were reported in a previously paper (1990). The study involved 575 incident cases of rectal cancer and 1400 controls at age range from 30-70.The study showed that increased consumption of cruciferous vegetables (Veg), fresh beans, fresh fruits, garlic, sea weeds and Veg oil were inversely related to the risk of rectal cancer. The intake of pork elevated the risk. Dietary fiber, vitamin C and carotene, independent of other nutrients, had the protective effect against developing rectal cancer. The intakes of several lipids, including total fat, saturated, mono-unsaturated, polyunsatura-ted,oleic, linoleic, and linolcnic,were slightly related with the risk of the cancer. Cholesterol significantly decreased the risk for females and had a significant linear trend. Investigation of nutrients revealed that ?-tocopherol and FOCC (fatty acid of odd carbon chain) decreased the relative risk for females. Analyses compared with other studies carried out in the Western countries (high incidence areas) showed that there may be a difference in risk factors of rectal cancer in diet between the Eastern countries (low incidence areas) and the West.