Vegetables, cereals and meat are foods of interest in the aetiology of colon cancer. While vegetable consumption is considered to be protective against colon cancer, the role of cereals in colon carcinogenesis remains controversial. Colon cancer mortality has rapidly increased in Japan since the 1950s. We examined the trend of consumption of vegetables, cereals and meat in Japan during the period from 1950 to 1995. Vegetable consumption has been almost constant during the period, whereas cereal consumption has declined drastically. Meat consumption increased up until the 1970s, but the increase has been minimal thereafter. These consumption patterns suggest that cereals are an important dietary factor determining the risk of colon cancer in Japan.