Association between dietary vitamin C intake and risk of esophageal cancer: A dose-response meta-analysis.
While several epidemiological studies have investigated the association between vitamin C and risk of esophageal cancer, the results remain inconsistent. In the present study, a meta-analysis was conducted to assess the impact of dietary vitamin C intake on esophageal cancer risk. Online databases were searched up to March 29, 2015, for studies on the association between dietary vitamin C intake and esophageal cancer risk. Pooled risk ratios (RRs) or odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Dose-response analyses were performed using the method of restricted cubic splines with four knots at percentiles of 5, 35, 65 and 95% of the distribution. Publication bias was estimated using Egger's tests and funnel plots. In all, 15 articles were included in this meta-analysis, including 20 studies, containing 7063 controls and 3955 cases of esophageal cancer. By comparing the highest vs. the lowest categories of vitamin C intake, we found that vitamin C was inversely associated with the risk of esophageal cancer [overall OR = 0.58, 95% CI = 0.49-0.68, I(2) = 56%]. A linear dose-response relationship was found. With an increase in dietary vitamin C intake of 50 mg/day, the risk of esophageal cancer statistically decreased by 13% (OR = 0.87, 95% CI = 0.80-0.93, p(linearity) = 0.0002). In conclusion, our analysis suggested that the higher intake of dietary vitamin C might have a protective effect against esophageal cancer.
Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, Henan, 450001, China.
Yacong
Y
Bo
The North Hospital of the Ninth People's Hospital of Shanghai City, Shanghai, 201999, China.
Yan
Y
Lu
Henan Tumor Hospital, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China.
Yan
Y
Zhao
Henan Tumor Hospital, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China.
Erjiang
E
Zhao
Henan Tumor Hospital, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China.
Ling
L
Yuan
Henan Tumor Hospital, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China.
Weiquan
W
Lu
Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, Henan, 450001, China.
Lingling
L
Cui
Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, Henan, 450001, China.
Quanjun
Q
Lu
D001205:Ascorbic Acid / Q000008:administration & dosage*; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004938:Esophageal Neoplasms / Q000453:epidemiology*; D006801:Humans; D016017:Odds Ratio; D012307:Risk Factors; D014815:Vitamins / Q000008:administration & dosage*
D014815:Vitamins; D001205:Ascorbic Acid
dietary vitamin C; dose-response; esophageal cancer; intake; meta-analysis