The risk of lung cancer among cooking adults: a meta-analysis of 23 observational studies.

Purpose: Cooking has been regarded as a potential risk factor for lung cancer. We aim to investigate the evidence of cooking oil fume and risk of lung cancer.

Methods: Medline and Embase were searched for eligible studies. We conducted a meta-analysis to summarize the evidences of case-control or cohort studies, with subgroup analysis for the potential discrepancy. Sensitivity analysis was employed to test the robustness.

Results: We included 23 observational studies, involving 9411 lung cancer cases. Our meta-analysis found that, for cooking female, the pooled OR of cooking oil fume exposure was 1.98 (95% CI 1.54, 2.54, I  = 79%, n = 15) among non-smoking population and 2.00 (95% CI 1.46, 2.74, I  = 75%, n = 10) among partly smoking population. For cooking males, the pooled OR of lung cancer was 1.15 (95% CI 0.71, 1.87; I  = 80%, n = 4). When sub grouped by ventilation condition, the pooled OR for poor ventilation was 1.20 (95% CI 1.10, 1.31, I  = 2%) compared to good ventilation. For different cooking methods, our results suggested that stir frying (OR = 1.89, 95% CI 1.23, 2.90; I  = 66%) was associated with increased risk of lung cancer while not for deep frying (OR = 1.41, 95% CI 0.87, 2.29; I  = 5%). Sensitivity analysis suggested our results were stable.

Conclusion: Cooking oil fume is likely to be a risk factor for lung cancer for female, regardless of smoking status. Poor ventilation may increase the risk of lung cancer. Cooking methods may have different effect on lung cancer that deep frying may be healthier than stir frying.