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Folate, folic acid and 5-methyltetrahydrofolate are not the same thing

Scaglione et al., Xenobiotica, doi:10.3109/00498254.2013.845705
Feb 2014  
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Review of folate as an essential micronutrient and possible forms for supplementation in case of deficiency - folic acid, folinic acid or 5-methyltetrahydrofolate (5-MTHF). Authors note that 5-MTHF has important advantages over synthetic folic acid, and may prevent potential negative effects of unconverted folic acid in the peripheral circulation.
See Karakousis et al. for another review covering vitamin B9 for COVID-19.
Scaglione et al., 4 Feb 2014, peer-reviewed, 2 authors.
This PaperVitamin B9All
Folate, folic acid and 5-methyltetrahydrofolate are not the same thing
Francesco Scaglione, Giscardo Panzavolta
Xenobiotica, doi:10.3109/00498254.2013.845705
1. Folate, an essential micronutrient, is a critical cofactor in one-carbon metabolism. Mammals cannot synthesize folate and depend on supplementation to maintain normal levels. Low folate status may be caused by low dietary intake, poor absorption of ingested folate and alteration of folate metabolism due to genetic defects or drug interactions. 2. Folate deficiency has been linked with an increased risk of neural tube defects, cardiovascular disease, cancer and cognitive dysfunction. Most countries have established recommended intakes of folate through folic acid supplements or fortified foods. External supplementation of folate may occur as folic acid, folinic acid or 5-methyltetrahydrofolate (5-MTHF). 3. Naturally occurring 5-MTHF has important advantages over synthetic folic acid -it is well absorbed even when gastrointestinal pH is altered and its bioavailability is not affected by metabolic defects. Using 5-MTHF instead of folic acid reduces the potential for masking haematological symptoms of vitamin B 12 deficiency, reduces interactions with drugs that inhibit dihydrofolate reductase and overcomes metabolic defects caused by methylenetetrahydrofolate reductase polymorphism. Use of 5-MTHF also prevents the potential negative effects of unconverted folic acid in the peripheral circulation. 4. We review the evidence for the use of 5-MTHF in preventing folate deficiency.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article. The authors thank Chiara Cipollina and Mary Hines for providing editorial assistance on behalf of inScience Communications, Springer Healthcare. This assistance was sponsored by Zambon.
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