Maternal dietary nitrate intake and risk of neural tube defects: A systematic review and dose-response meta-analysis. (August 2018)

• Record Type: Journal Article
• Authors: Kakavandi, Nader Rahimi; Hasanvand, Amin; Ghazi-Khansari, Mahmoud; Sezavar, Ahmad Habibian; Nabizadeh, Hassan; Parohan, Mohammad
• Is Part Of: Food and chemical toxicology. Volume 118(2018)
• Page Start: 287
• Page End: 293
• Publication Date: 2018-08
• Subjects: Meta-analysis -- Nitrate -- Neural tube defects -- Systematic review; Toxicology -- Periodicals; Food poisoning -- Periodicals; Food Poisoning -- Periodicals; Toxicology -- Periodicals; Toxicologie -- Périodiques; Intoxications alimentaires -- Périodiques; Food poisoning; Toxicology; Periodicals; Electronic journals; 615.9
• DOI: 10.1016/j.fct.2018.05.033
• Languages: English
• ISSNs: 0278-6915

Abstract

Abstract: Despite growing evidence for the potential teratogenicity of nitrate, knowledge about the dose-response relationship of dietary nitrate intake and risk of specific birth defects such as neural tube defects (NTDs) is limited. Therefore, the aim of this meta-analysis was to synthesize the knowledge about the dose-response relation between maternal dietary nitrate intake and the risk of NTDs. We conducted a systematic search in PubMed, ISI Web of Science and Scopus up to February 2018 for observational studies. Risk ratios (RRs) and 95% confidence intervals (95% CI) were calculated using a random-effects model for highest versus lowest intake categories. The linear and non-linear relationships between nitrate intake and risk of NTDs were also investigated. Overall, 5 studies were included in the meta-analyses. No association was observed between nitrate intake and NTDs risk in high versus low intake (RR: 1.33; 95% CI: 0.89–1.99, p = 0.158) and linear dose-response (RR: 1.03; 95% CI: 0.99–1.07, p = 0.141) meta-analysis. However, there were positive relationships between nitrate intake and risk of NTDs in non-linear (pnon-linearity <0.05) model. Findings from this dose-response meta-analysis indicate that maternal nitrate intake higher than ∼3 mg/day is positively associated with NTDs risk. Highlights: Maternal exposure to nitrate from diet is associated with an increased risk of NTDs; however, the results are inconclusive. This is the first review to investigate the dose-response association between maternal nitrate intake and risk of NTDs. The risk of NTDs increased with increasing intake of maternal dietary nitrate above ∼3 mg/day.