The necessity of folic acid intake in preventing neural tube defects, a systematic review

The necessity of folic acid intake in preventing neural tube defects, a systematic review
zahra baradaran,^1,* Mojgan Yaghoubi,² Rasul Saberi,³ Ailar Hashtroody,⁴ AmirAli Moodi Ghalibaf,⁵
1. Student Research Committee, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran.
2. Midwifery Department, Faculty of Medical Science, Islamic Azad University, Mashhad, Iran.
3. Biology Department, Faculty of Basic Science, Islamic Azad University, Mashhad, Iran.
4. Student research commitee ,Health Services Management Department, Faculty of Health, Qazvin University of Medical Sciences, Qazvin, Iran.
5. Student Research Committee, FacuAlty of Medicine, Mashhad University of Medical Sciences, Mashhad,Iran
Introduction: Neural tube defects (NTDs) are severe birth defects of the central nervous system that result from a failure of neural tube closure process. The global incidence of NTD varies between 1 and 10/1000 births. This variation is likely to indicate different contributions from risk factors such as folic acid deficiency, maternal diabetes and a high glycemic index diet. Folate is a key micronutrient needed for normal cellular function. The use of folic acid will effectively reduce NTD by public health measures before and during early pregnancy.
Methods: We searched the literature available in PubMed, Google scholar, Sciencedirect, SID and Magiran databases for English articles published between 2000 and 2020. For this purpose, we used the words Prevention-NTDs, NTD dietary improvement, Neural tube defects and folic acid deficiency and neural tube defects as keyphrases. Among 100 articles found, 20 were irrelevant then excluded and 80 related articles were used.
Results: In 1965 the first observation of a link between folate deficiency and NTDs was published. in 1984–1991 The Hungarian randomized controlled trial of periconceptional multivitamin supplementation containing folic acid (0.8 mg) showed a substantial reduction in the first incidence of NTDs. However, Folic acid deficiency does not cause NTD in mice when genetic predisposition is not present. Another important risk factor of NTD is maternal obesity. Infants of obese mothers are more likely to have NTDs than children of normal weight. Therefore, obesity is not affected by supplementation of folate.However, Some of NTDs are potentially folic acid resistant. This notion is established in NTD mouse models in which folic acid inhibits other genetic forms while others are resistant to folic acid.possible adjunct therapy used in animal studies is inositol, which is successful in preventing a significant proportion of spinal NTDs, for which folic acid is ineffective.
Conclusion: The results show that the consumption of folic acid can be effective in the first occurrence of NTD. However, the relationship between folic acid, genetic and environmental factors is not yet well understood. Such models provide an opportunity to explore potential risks and create new preventative therapies.
Keywords: NTD,Prevention,Improvement,Diet,Folic acid deficiency