Long Bangce, Jiang Chenglin, Liu Zhongjian, Wan Ping, Guo Qiang
Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China.
Department of Gastroenterology, The First People's Hospital of Yunnan Province, No. 157 Jinbi Road, Kunming, 650032, Yunnan, China.
Nutr Metab (Lond). 2025 Jul 25;22(1):84. doi: 10.1186/s12986-025-00973-6.
Recent studies have indicated that dietary nitrate intake from plant sources offers numerous health benefits. However, the relationships between the intake of plant-derived nitrates and nitrites and the risk of digestive system cancers (DSCs) remain unclear. This study aimed to quantify the associations between dietary nitrate and nitrite from plant sources and the risk of DSCs via a systematic review and meta-analysis.
We conducted extensive literature searches of the PubMed, Embase, Scopus, Web of Science, CINAHL, Cochrane Library, CNKI, VIP, Wanfang, and CBM databases up to April 2024. STATA 14.0 was applied for meta-regression and meta-analysis, and fixed or random effects models were used to calculate the pooled relative risks and 95% confidence intervals. Sensitivity and subgroup analyses were conducted to explore sources of heterogeneity.
Our analysis included 13 articles with a total of 897,585 participants, which included 10 different types of digestive tumors. The pooled results indicated no significant association between high (median: >134.9 mg/day) [RR = 0.92; 95% CI (0.82-1.03); P = 0.14] or moderate (median: 83.0-133.1 mg/day) [RR = 0.95; 95% CI (0.89-1.02); P = 0.186] nitrate intake and DSCs. Similarly, neither high (median: >0.91 mg/day) [RR = 0.91; 95% CI (0.84-1.00); P = 0.05] nor moderate (median: 0.75 mg/day) [RR = 0.96; 95% CI (0.89-1.04); P = 0.355] nitrite intake was correlated with DSCs. However, a negative association was observed between nitrate or nitrite intake and DSCs when the data were stratified by subgroup variables such as study type, sex, region, antioxidant intake, and fibre intake. A meta-regression dose‒response analysis revealed that the risk of gastric cancer was negatively associated with the median intake of plant-derived nitrates [slope= -0.0047 per mg/day; 95% CI (-0.0086--0.0008); P = 0.022].
Plant-derived nitrate and nitrite intakes were not significantly associated with DSCs. This relationship may be affected by subgroup variables, and a dose‒response analysis indicated that higher nitrate intake was linked to a reduced risk of gastric cancer.
近期研究表明，从植物来源摄入膳食硝酸盐对健康有诸多益处。然而，植物源性硝酸盐和亚硝酸盐的摄入量与消化系统癌症（DSCs）风险之间的关系仍不明确。本研究旨在通过系统评价和荟萃分析来量化植物来源的膳食硝酸盐和亚硝酸盐与DSCs风险之间的关联。
我们对截至2024年4月的PubMed、Embase、Scopus、Web of Science、CINAHL、Cochrane图书馆、中国知网、维普、万方和中国生物医学文献数据库进行了广泛的文献检索。使用STATA 14.0进行荟萃回归和荟萃分析，并采用固定或随机效应模型计算合并相对风险和95%置信区间。进行敏感性和亚组分析以探索异质性来源。
我们的分析纳入了13篇文章，共897,585名参与者，其中包括10种不同类型的消化肿瘤。汇总结果表明，高（中位数：>134.9毫克/天）[RR = 0.92；95% CI（0.82 - 1.03）；P = 0.14]或中等（中位数：83.0 - 133.1毫克/天）[RR = 0.95；95% CI（0.89 - 1.02）；P = 0.186]的硝酸盐摄入量与DSCs之间无显著关联。同样，高（中位数：>0.91毫克/天）[RR = 0.91；95% CI（0.84 - 1.00）；P = 0.05]或中等（中位数：0.75毫克/天）[RR = 0.96；95% CI（0.89 - 1.04）；P = 0.355]的亚硝酸盐摄入量与DSCs均无相关性。然而，当按研究类型、性别、地区、抗氧化剂摄入量和纤维摄入量等亚组变量对数据进行分层时，观察到硝酸盐或亚硝酸盐摄入量与DSCs之间存在负相关。荟萃回归剂量反应分析显示，胃癌风险与植物源性硝酸盐的中位数摄入量呈负相关[斜率 = -0.0047每毫克/天；95% CI（-0.0086 - -0.0008）；P = 0.022]。
植物源性硝酸盐和亚硝酸盐的摄入量与DSCs无显著关联。这种关系可能受亚组变量影响，剂量反应分析表明较高的硝酸盐摄入量与降低的胃癌风险相关。
