OBJECTIVE: To evaluate the association between wholegrain products intake and other dietary, lifestyle, anthropometric and socio-economic factors. DESIGN: Cross-sectional study, with data on diet, lifestyle and socio-economic factors obtained from questionnaires. Anthropometric measurements were collected by trained professionals. Multiple linear and principal components regression analyses were used in statistical analyses. SETTING: Part of the Diet, Cancer and Health study, a prospective cohort study to evaluate the aetiological role of diet on cancer risk, conducted in the greater Copenhagen and Aarhus area, Denmark. SUBJECTS: Men and women (n 54 720) aged 50-64 years. RESULTS: In multiple linear regression analyses focusing on individual dietary factors, intake of wholegrain products was associated with intake of all dietary factors studied (fish, red meat, poultry, processed meat, dairy products, fruits, vegetables, cakes and refined-grain products). The strongest positive associations were seen for intake of vegetables and processed meat, whereas the strongest negative associations were seen for intake of red meat and refined-grain products. Regression analyses on dietary patterns identified by principal components analysis yielded similar results. Also, wholegrain products intake was positively associated with cycling, taking dietary supplements and high school education, and negatively associated with intake of alcohol, BMI and smoking. CONCLUSIONS: Intake of wholegrain products is associated with other dietary factors, healthier lifestyle habits and higher socio-economic status. Therefore future studies need to account for the possible confounding by other dietary and lifestyle-related parameters when investigating relationships between wholegrain products intake and disease risk.