DIETARY FACTORS AND LUNG-CANCER AMONG MEN IN WEST SWEDEN

Background. Previous studies have reported an association between tea drinking and lung cancer. In view of these data, the relationship betw een tea drinking as well as other dietary factors and lung cancer was investigated in a case-control study in the west of Sweden. Methods. P atients with suspected lung cancer were collected from pulmonary units at central hospitals in the area investigated, and population control s were matched for age, The material reported here comprises 308 male cases with a confirmed diagnosis of lung cancer and 504 controls. The participants were interviewed by specially trained nurses, using a que stionnaire to assess smoking, dietary habits, occupational exposures a nd conditions in the residential area (local air pollution). This pape r reports the results from dietary factors studied with a food frequen cy technique. Results. The results demonstrated a strong protective ef fect of vegetables (odds ratio [OR] = 0.69, 95% confidence interval [C I] : 0.46-1.05, and OR = 0.37, 95% CI : 0.23-0.61 for intermediate and high consumption classes respectively), A low OR was consistent for a ll histological types of lung cancer. High consumption of fruits did n ot show any similar protective effect. Drinking milk was associated wi th a dose-response related risk increase after adjustment for smoking and vegetable consumption (P for trend = 0.07). Odds ratio was 1.73, 9 5% CI : 1.00-3.01 for high consumption of milk. Conclusions. High inta ke of vegetables had a strong protective effect among males. Diet is t hus a potential confounding factor in studies on lung cancer and envir onmental factors and should thus be taken into consideration in the pl anning of such studies.