Joint effects of dietary trace metals and DNA repair capacity in lung cancer risk.

In a large case-control study, we previously reported that dietary intakes of zinc (Zn) and copper (Cu), but not selenium (Se), were inversely associated with lung cancer risk. Because Zn, Cu, Se, iron (Fe), and calcium (Ca) are important for maintaining DNA stability, we examined their associations with DNA repair capacity (DRC) measured by the lymphocyte host-cell reactivation assay in 1,139 cases and 1,210 of the controls. Dietary intake was reported in a food frequency questionnaire.