title: Association between dietary antioxidant vitamins intake/blood level and risk of gastric cancer.
abstract: We aimed to systematically evaluate the association between dietary intake/blood levels of antioxidant vitamins (vitamin C, vitamin E, β-carotene, and α-carotene) and gastric cancer risk. Systematic literature searches were conducted until April 2013 in Pubmed and Embase to identify relevant studies. Either a fixed- or a random-effects model was adopted to estimate overall odds ratios (ORs). Dose-response, meta-regression, subgroup, and publication bias analyses were applied. Forty articles were finally included in the present study. Higher dietary intake of vitamin C, vitamin E, β-carotene, and α-carotene was inversely associated with gastric cancer risk (for vitamin C, pooled OR=0.58, 95% CI 0.51-0.65; for vitamin E, pooled OR=0.65, 95% CI 0.57-0.74; for β-carotene, pooled OR=0.59, 95% CI 0.49-0.70; for α-carotene, pooled OR=0.69, 95% CI 0.52-0.93). Subgroup analyses suggested the effects of these antioxidant vitamins were different in gastric cancer subtypes. As indicated by dose-response analysis, a 100 mg/day increment of vitamin C intake conferred an OR of 0.78 (95% CI 0.67-0.90); a 15 mg/day increment of vitamin E intake conferred an OR of 0.79 (95% CI 0.66-0.94); and a 5 mg/day increment in β-carotene intake conferred an OR of 0.80 (95% CI 0.60-1.04). No significant association was observed between blood vitamin C, α-tocopherol, γ- tocopherol, β-carotene and α-carotene levels and gastric cancer risk. In conclusion, dietary intake of vitamin C, vitamin E, β-carotene and α-carotene was inversely associated with gastric cancer risk while no such association was observed for blood levels of these antioxidant vitamins, thus the results should be interpreted cautiously.
authors: Department of Epidemiology and Health Statistics, Zhejiang University School of Public Health, Hangzhou, China.
authors: Peiwei
authors: P
authors: Li
authors: Honghe
authors: H
authors: Zhang
authors: Jiamin
authors: J
authors: Chen
authors: Yu
authors: Y
authors: Shi
authors: Jianting
authors: J
authors: Cai
authors: Jun
authors: J
authors: Yang
authors: Yihua
authors: Y
authors: Wu
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage*; D004032:Diet; D005260:Female; D006801:Humans; D008297:Male; D012306:Risk; D013274:Stomach Neoplasms / Q000097:blood* / Q000453:epidemiology*; D014815:Vitamins / Q000008:administration & dosage* / Q000097:blood*
chemical_list: D000975:Antioxidants; D014815:Vitamins
keywords: antioxidant vitamin; blood level; dietary intake; gastric cancer; risk