Scientists at the National Cancer Center in Tokyo report the findings of their research into the role of diet in colon cancer in the July 10th issue of the International Journal of Cancer. The researchers found that both the meat-laden "Western" diet and the traditional, salty diet of the Japanese apparently increase the risk of colon cancer, at least for women.

This was a relatively large study where more than 42,000 adults were followed for 10 years. It seems that women,  but not men, with either a Western pattern of eating or a diet heavy in traditional Japanese foods like salted fish and pickled vegetables had a higher risk of colon cancer compared with women who were considered healthy eaters by the researchers.

The investigators defined three dietary patterns based on survey respondents' reported eating habits. The “Western” diet was marked by high intakes of meat, poultry, cheese and bread and butter. The "traditional" diet was structured around rice, miso soup, salted fish and pickled vegetables. The "healthy" one included high amounts of fruits, vegetables, soy products, beans and dairy.

Overall, women whose diets were the most Western had more than double the risk of developing colon cancer as women with the least Westernized diets. Similarly, women who ate the most traditional foods were twice as likely as those who ate the fewest to be diagnosed with colon cancer.

The healthy eating pattern was not linked to colon cancer risk at all.

Summary of the study available here.