BACKGROUND: Most cured meats contain nitrites. Nitrites generate oxidative-nitrative stress and were shown in animal models to cause emphysema. Prospective epidemiologic data on cured meats and chronic obstructive pulmonary disease (COPD), however, are sparse. OBJECTIVE: We examined the relation between cured meat consumption and the prospective risk of newly diagnosed COPD in women. DESIGN: This was a prospective cohort study of 71 531 women from the Nurses' Health Study who completed a validated dietary questionnaire at baseline in 1984 and had no baseline COPD or a report of asthma. Participants were aged 38-63 y in 1984 and were followed for 16 y. RESULTS: A total of 750 new cases of COPD were documented during the follow-up. Cured meat consumption was positively associated with COPD risk after adjustment for age, smoking, and multiple other potential confounders. The adjusted relative risks of COPD across categories of cured meat consumption (never or almost never, 1-3 servings/mo, 1 serving/wk, 2-3 servings/wk, and > or = 4 servings/wk) were 1.0, 1.14 (95% CI: 0.78, 1.66), 1.15 (95% CI: 0.79, 1.69), 1.40 (95% CI: 0.96, 2.05), and 1.51 (95% CI: 1.00, 2.27), respectively, (P for trend = 0.005). This positive association was present among both past (P for trend = 0.02) and current (P for trend = 0.03) smokers. No association was observed among never smokers, probably because of the small number of COPD cases in these women. CONCLUSION: Frequent cured meat consumption was associated with an increased risk of newly diagnosed COPD among women who smoke.