The importance of dietary factors in colon carcinogenesis was analyzed as part of a case-control study from Northern Sweden encompassing 312 cases and 623 controls. Data on 28 different food items, each divided into consumption before and after the age of 25, were collected by a food frequency questionnaire. Mantel-Haenszel odds ratios (MH-ORs) were calculated for various food items and nutritients and are given in parentheses where A represents consumption before and B after the age of 25. Reduced MH-ORs were seen for daily cheese intake (A=0.64, B=0.41) and also for intake of crisp bread, boiled and fried fish although not significantly. A non-significantly decreased risk was seen for fibre-rich food. When food items were grouped with regard to their content of certain nutrients, decreased risks were associated with food rich in selenium (A=0.74, B=0.82). Also food rich in vitamin C gave a reduced MH-OR but only for intake before the age of 25 (A=0.75, B=1.09). For daily consumption of 2 or more cups of tea a reduced MH-OR of 0.61 was seen. Frequent intake of smoked food gave increased MH-ORs for both age groups (A=1.52, B=1.36) whereas high fat intake was not identified as a risk factor for colon cancer. Intake of alcohol or coffee was not associated with colon cancer risk in this study.