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The 13th World Conference on Tobacco OR Health
Building capacity for a tobacco-free world
July 12-15, 2006, Washington, DC, USA
Objective: to analyse the possible interaction between tobacco consumption and vegetable intake.
Methods: We analyze data from a hospital-based case-control study on lung cancer including 295 histologically confirmed cases and 322 controls. Controls were individuals attending the hospital for trivial surgery. There was a minimum age limit of 35 years and sampling was carried out a sex-frequency basis. Three categories of vegetable intake and another 3 of tobacco habit were created yielding 9 categories in total. The analysis was performed with logistic regression taking the status of case or control as the dependent variable. The results were adjusted for age, sex, and occupation.
Results: Green leafy vegetables were found to have a statistically significant protective effect on non-smokers. Among smokers, the risk declined in light-moderate smokers and in heavy smokers when the intake of vegetables increases. Taking those individuals non smokers and consuming vegetables less than 5 times per week as the reference category, the risk of lung cancer for those nonsmokers consuming vegetables more than once per day was 0,37 (CI 95% 0,15-0,92). The risk of lung cancer for those light-moderate smokers consuming vegetables less than 5 times per week was 3,14 (CI 95% 1,21-8,17) and for those consuming vegetables more than once per day was 2,29 (CI% 1,04-5,02). The risk of lung cancer for heavy smokers consuming vegetables less than 5 times per week was 17,47 (CI% 5,75-53,10) and for those consuming vegetables more than once per day was 6,98 (CI% 3,04-15,98).