Zhong Jiamin, Li Peiwei, Zheng Fang, Li Yating, Lu Wei, Chen Hanwen, Cai Jianting, Xia Dajing, Wu Yihua
Department of Toxicology of School of Public Health and Department of Gynecologic Oncology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Department of Gastroenterology, Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, 310009, China.
Food Funct. 2024 Aug 12;15(16):8217-8237. doi: 10.1039/d4fo00350k.
Experimental studies have shown that vitamin C has anti-cancer effects, but previous meta-analyses have indicated that the role of vitamin C in digestive system cancers (DSCs) is controversial. In this study, a systematic review and meta-analysis of the relationship between dietary intake/plasma concentration of vitamin C and the risk of DSC was conducted, evaluating 32 prospective studies with 1 664 498 participants. Dose-response and subgroup analyses were also performed. Systematic literature searches were performed in PubMed, EMBASE and Web of Science databases until 9 September 2023. Vitamin C intake significantly reduced DSCs risk (RR = 0.88, 95% confidence interval (CI) 0.83 to 0.93). The subgroup analyses showed the risks of oral, pharyngeal, and esophageal (OPE) cancers (0.81, 0.72 to 0.93), gastric cancer (0.81, 0.68 to 0.95), and colorectal cancer (0.89, 0.82 to 0.98) were negatively correlated with vitamin C intake, and the effect of vitamin C was different between colon cancer (0.87, 0.77 to 0.97) and rectal cancer (1.00, 0.84 to 1.19). However, plasma vitamin C concentration was only inversely associated with gastric cancer risk (0.74, 0.59 to 0.92). Dose-response analysis revealed that 250 and 65 mg day vitamin C intakes had the strongest protective effect against OPE and gastric cancers respectively. These estimates suggest that vitamin C intake could significantly reduce gastrointestinal cancer incidence, including OPE, gastric, and colon cancers. Plasma vitamin C has a significant reduction effect on the incidence of gastric cancer only, but additional large-scale clinical studies are needed to determine its impact on the incidence of DSCs.
实验研究表明维生素C具有抗癌作用，但先前的荟萃分析表明维生素C在消化系统癌症（DSCs）中的作用存在争议。在本研究中，对维生素C的膳食摄入量/血浆浓度与DSC风险之间的关系进行了系统评价和荟萃分析，评估了32项涉及1664498名参与者的前瞻性研究。还进行了剂量反应和亚组分析。截至2023年9月9日，在PubMed、EMBASE和科学网数据库中进行了系统的文献检索。维生素C摄入量显著降低了DSC风险（风险比=0.88，95%置信区间（CI）为0.83至0.93）。亚组分析显示，口腔、咽和食管癌（OPE）（0.81，0.72至0.93）、胃癌（0.81，0.68至0.95）和结直肠癌（0.89，0.82至0.98）的风险与维生素C摄入量呈负相关，维生素C在结肠癌（0.87，0.77至0.97）和直肠癌（1.00，0.84至1.19）中的作用有所不同。然而，血浆维生素C浓度仅与胃癌风险呈负相关（0.74，0.59至0.92）。剂量反应分析表明，每天摄入250毫克和65毫克维生素C分别对OPE和胃癌具有最强的保护作用。这些估计表明，维生素C摄入量可显著降低胃肠道癌症的发病率，包括OPE、胃癌和结肠癌。血浆维生素C仅对胃癌发病率有显著降低作用，但需要更多大规模临床研究来确定其对DSC发病率的影响。
