Eating a variety of fruits and vegetables may protect smokers against lung cancer, according to new data from a multicenter cohort study.
The inverse relationship between variety in vegetable consumption and lung cancer risk was independent of quantity and restricted to current smokers.
Frederike L. Büchner of The National Institute of Public Health and the Environment, Bilthoven, The Netherlands, and associates evaluated the relationship between variety in fruit and vegetable consumption, independent of quantity, and risk of primary lung cancer among participants in the ongoing European Prospective Investigation into Cancer and Nutrition (Cancer Epidemiol Biomarkers Prev. 2010;19:2278-2286). The fruits included fresh, dried, and canned fruits but not nuts, seeds, or olives. Vegetables did not include legumes, potatoes, and other tubers.
Of 452,187 participants with complete information, 1613 developed lung cancer over a mean follow-up period of 8.7 years.
The investigators found that with increasing variety of vegetable subgroups, the overall risk of lung cancer decreased (hazard ratio for the highest vs lowest quartile, 0.77) but only among current smokers. When analyzed by cancer subtype, higher variety in fruit and vegetable intake was inversely associated with risk of squamous cell carcinomas, driven mainly by the effect in current smokers.
The researchers note, however, that because smoking is the primary risk factor for lung cancer, public health efforts should focus on smoking prevention and cessation.