1996 年 15 巻 2 号 p. 77-84
The daily intake of total dietary fiber (TDF) was evaluated from data collected by the National Nutrition Survey in Japan over a period of 41 years since1947. The interrelationships between dietary fiber, other nutrient intake and the mortality from colon cancer (MCC) were determined by a simple correlation coefficient and a time-series correlation coefficient. TDF intake per capita decreased rapidly from 27.4 g in 1947 to 15.8 g in 1963, and subsequently decreased at a lesser rate to15.3 g in 1987. The interrelationship between MCC and TDF intake could be represented by two linear regression lines, with similar findings also being observed for fat, fat energy ratio and fat/TDF. MCC has increased rapidly since the daily intake of TDF dropped to less than 18 g. A time-series analysis indicates that MCC has a significantly positive maximum correlation with the intake of total fat and with the fat energy ratio after a 16-year delay. MCC was negatively correlated with TDF after a 15-27 year delay, the maximum correlation existing with a 24-year lag (r = 0.918). Fat/TDF showed the most striking correlation with MCC with a 16-year lag (r =- 0.994) among all the parameters. It is suggested that the cause of increased MCC in Japan is positively related to the increased intake of fat. In addition, the decrease in TDF intake has accelerated MCC after a delay of 24 years. The importance of fat/ TDF as a nutritional criterion for the incidence of colon cancer needs to be betterrecognized.
