Factor analysis of digestive cancer mortality and food consumption in 65 Chinese counties.

Dietary factors were analyzed for the regional difference of GI tract cancer mortality rates in China. Sixty-five rural counties were selected among a total of 2,392 counties to represent a range of rates for seven most prevalent cancers. The dietary data in the selected 65 counties were obtained by three-day dietary record of households in 1983. The four digestive cancer mortality rates (annual cases per 100,000 standardized truncated rates for ages 35-64) and per capita food consumption were analyzed by the principal components factor analysis. Esophageal cancer associated with poor area, dietary pattern rich in starchy tubers, and salt, lack of consumption of meat, eggs, vegetables and rice. Stomach cancer seemed to be less associated with diet in this study because of its small model Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy, suggesting some other carcinogenic factors would play more important role in the development of this cancer in China. The colon and rectal cancer showed close relation to diet; rich in sea vegetables, eggs, soy sauce, meat and fish, while lack in consumption of milk and dairy products. Rapeseed oil was more important risk factor for colon cancer than that of rectum. Rice, processed starch and sugar were closely associated with colon cancer, supporting the insulin/colon cancer hypothesis.