{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T07:08:14Z","timestamp":1789542494869,"version":"build-2803163510"},"reference-count":112,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T00:00:00Z","timestamp":1726617600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ITF RESEARCH PHARMA","award":["MITAL5GV"],"award-info":[{"award-number":["MITAL5GV"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: Folic acid (FA), which in its chemical form is pteroylglutamic acid, is the fully oxidised, water-soluble, monoglutamic form of vitamin B9. This compound is part of the folate group but with higher bioavailability, and it is found in vitamin supplements and fortified foods and drugs. Folate metabolism is complex and associated with various metabolic pathways, all of which confer protection on the cell and allow its survival. Methods: We conducted a non-systematic search of articles published in English and Spanish including controlled trials, cohort studies, systematic re-views, and meta-analyses were included, as well as key studies in animal models related to pharmacokinetic studies. Search terms encompassed: \u201cfolic acid\u201d, \u201cfolates\u201d, \u201c5-metyltetrahydrofolate\u201d, \u201c5-MTHF\u201d, \u201cneural tube defects\u201d, \u201csupplementation\u201d, \u201cfortification\u201d, AND \u201chomocysteine\u201d Results: A crucial role demonstrated for FA is to help prevent neural tube defects (NTDs). However, more studies are definitely still needed to establish 5-MTHF as a safe and effective therapeutic approach comparable with FA. Moreover, there is a lack of clinical studies that evaluate the efficacy of 5-MTHF supplementation in the prevention of NTDs. The present evidence-based narrative review discusses differences between FA and 5-MTHF in terms of structure, metabolism, bioavailability, clinical efficacy, and safety. Conclusions: Despite the potential value of 5-MTHF as an alternative to FA, clinical studies would be urgently needed to support the efficacy, dosage, timing, and\/or safety of its use as a supplement.<\/jats:p>","DOI":"10.3390\/nu16183154","type":"journal-article","created":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T09:49:19Z","timestamp":1726652959000},"page":"3154","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Supplementation with Folic Acid or 5-Methyltetrahydrofolate and Prevention of Neural Tube Defects: An Evidence-Based Narrative Review"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7323-4420","authenticated-orcid":false,"given":"Mar\u00eda de Lourdes","family":"Samaniego-Vaesken","sequence":"first","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1289-3745","authenticated-orcid":false,"given":"Carmen","family":"Morais-Moreno","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6559-8002","authenticated-orcid":false,"given":"Alejandra","family":"Carretero-Krug","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2836-4642","authenticated-orcid":false,"given":"Ana Mar\u00eda","family":"Puga","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5103-3732","authenticated-orcid":false,"given":"Ana Mar\u00eda","family":"Montero-Bravo","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4401-1233","authenticated-orcid":false,"given":"Teresa","family":"Partearroyo","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5158-4999","authenticated-orcid":false,"given":"Varela-Moreiras","family":"Gregorio","sequence":"additional","affiliation":[{"name":"Grupo USP-CEU de Excelencia \u201cNutrici\u00f3n para la vida (Nutrition for Life)\u201d, Ref: E02\/0720, Departamento de Ciencias Farmac\u00e9uticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"},{"name":"Instituto Universitario CEU Alimentaci\u00f3n y Sociedad, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanizaci\u00f3n Montepr\u00edncipe, 28660 Boadilla del Monte, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1146\/annurev-nutr-043020-091647","article-title":"Folic Acid and the Prevention of Birth Defects: 30 Years of Opportunity and Controversies","volume":"42","author":"Crider","year":"2022","journal-title":"Annu. 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