Could high serum folate be associated with adverse effects?

Document Type : Letter to the Editor


1 Department of Biology, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran

2 Research Center for Animal Development Applied Biology & Biology Department, Mashhad Branch, Islamic Azad University, Mashhad, Iran

3 Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

4 Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

5 Cancer Genetics Research Unit, Reza Radiotherapy and Oncology Center, Mashhad, Iran


Folate is an important water-soluble vitamin that is presented naturally in foods in particular vegetables, fruits, and whole grains. To which extent is this vitamin needed in our daily regimen is not fully known. Several studies have indicated that many complications, such as megaloblastic anemia, cardiovascular disease, neural tube defects, and numerous cancers, occur in humans when the body becomes deficient in folic acid. On the other hand, a few studies have shown thier concerns regarding the supplementation of folic acid, resulting in the development of existing tumors and alteration of normal patterns of DNA methylation. Although there is no clear evidence of aberrant DNA methylation and gene expression changes in response to “high” levels of folate  or folic acid intake, there are still some concerns. Therefore, its adverse effects especially on fetus and later stages of life should be carefully investigated.


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