Student Research Committee, Department and Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Department of Clinical Nutrition and Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Int J Vitam Nutr Res. 2024 Jun;94(3-4):264-274. doi: 10.1024/0300-9831/a000789. Epub 2023 Jul 20.
Animal models have suggested the carcinogenic effect of iron due to its oxidative potential. The lung is particularly vulnerable to oxidative stress. However, epidemiological studies investigating the association between dietary iron and the risk of lung cancer have reported inconclusive results. In this systematic review and meta-analysis, we aimed to clarify this association. We searched PubMed, Web of Science, Scopus and Google scholar for eligible articles published through May 2023 reporting the Relative Risk (RR), Hazard Ratio (HR) or Odds Ratio (OR) with 95% confidence interval (95% CI). Case-control and cohort studies that examined the relationship between dietary iron and lung cancer risk were included and review and meta-analyses articles, experimental studies, abstracts, letters to editor and studies with insufficient data were excluded. Finally, three case-control studies and 6 cohort studies were included. Random effect models were used to calculate the pooled results. Nine studies (cases =21,943, participants =1,542,993) were included. There were no significant associations between the highest dietary total iron (heme and non-heme) (RR: 1.09, 95% CI: 0.78 to 1.51) or heme iron (RR: 1.01, 95% CI: 0.73 to 1.38) intake compared to the lowest intake with lung cancer risk. Null-associations were also observed in the subgroup analysis based on smoking status and lung cancer histology. However, in the subgroup of women (cases =5074), heme iron was associated with a 14% increase in the risk of lung cancer (RR: 1.14, 95% CI: 1.01 to 1.29). The current results demonstrated that there is no significant relationship between dietary iron intake and the risk of lung cancer. However, a positive association was observed between dietary heme iron and the risk of lung cancer in women, which may require further investigation.
动物模型研究表明，铁具有氧化潜能，可能具有致癌作用。肺部特别容易受到氧化应激的影响。然而，调查膳食铁与肺癌风险之间关联的流行病学研究结果尚无定论。在本系统评价和荟萃分析中，我们旨在阐明这种关联。我们检索了 PubMed、Web of Science、Scopus 和 Google Scholar，以获取截至 2023 年 5 月发表的符合条件的文章，这些文章报告了相对风险（RR）、危险比（HR）或比值比（OR）及其 95%置信区间（95%CI）。纳入了研究膳食铁与肺癌风险之间关系的病例对照和队列研究，并排除了综述和荟萃分析文章、实验研究、摘要、给编辑的信和数据不足的研究。最终，纳入了 3 项病例对照研究和 6 项队列研究。使用随机效应模型计算汇总结果。纳入了 9 项研究（病例=21943，参与者=1542993）。最高膳食总铁（血红素和非血红素）（RR：1.09，95%CI：0.78 至 1.51）或血红素铁（RR：1.01，95%CI：0.73 至 1.38）摄入与最低摄入相比与肺癌风险无显著关联。根据吸烟状况和肺癌组织学进行亚组分析也观察到了零关联。然而，在女性亚组（病例=5074）中，血红素铁与肺癌风险增加 14%相关（RR：1.14，95%CI：1.01 至 1.29）。目前的结果表明，膳食铁摄入量与肺癌风险之间没有显著关系。然而，在女性中观察到膳食血红素铁与肺癌风险之间存在正相关，这可能需要进一步研究。
