Abstract
This study assessed the period taken for changes in dietary intake to exert the greatest influence on colorectal cancer (CRC) incidence in Japan. Using published data on dietary consumption of eight selected food groups (1965-2000) and age-standardized incidence rates of CRC (1975-2006), we constructed a causal multiple regression model for CRC with a 6- to 16-year lag time (every 2 years) between the time of intake and assessment of CRC incidence. The analyses showed that the patterns of the estimated effects of food group consumption varied with lag time, and suggested that there were positive contributions of animal fat, milk and dairy products, and potatoes, negative contributions of fish, legumes, green and yellow vegetables, and fruits, and no marked contribution of meat to CRC incidence.
