Exploratory correlations of dietary nutrients with prostate cancer mortality using over two decades of observations in Korea.

Prostate cancer is now the eighth leading cause of cancer mortality among Korean males. We investigated the relationship between various nutrients in the diet and prostate cancer deaths. Nutrient intake data were obtained from the Korean Nutrition Survey between 1963 and 1995 and the Korean National Health and Nutrition Examination Survey since 1998. Prostate cancer mortality rates for these time periods were obtained from the National Statistics Office. The correlations between different nutrients in the diet and mortality were calculated using Spearman's rank correlation analysis with a lag period. Carbohydrates and grains showed significant negative correlations while protein, fat, iron, and riboflavin, and the food groups including fruits, seafood, seasonings and drinks, meat, eggs, fish, and milk showed significant positive correlations. In addition, the correlation results for age-specific rates virtually coincided with the crude rate correlations. However, we urge caution in interpreting these results because they could merely be a consequence of the changing patterns of food consumption and the recording of deaths in Korea.