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Moravcová M, Siatka T, Krčmová LK, Matoušová K, Mladěnka P. Biological properties of vitamin B 12. Nutr Res Rev 2024:1-33. [PMID: 39376196 DOI: 10.1017/s0954422424000210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/09/2024]
Abstract
Vitamin B12, cobalamin, is indispensable for humans owing to its participation in two biochemical reactions: the conversion of l-methylmalonyl coenzyme A to succinyl coenzyme A, and the formation of methionine by methylation of homocysteine. Eukaryotes, encompassing plants, fungi, animals and humans, do not synthesise vitamin B12, in contrast to prokaryotes. Humans must consume it in their diet. The most important sources include meat, milk and dairy products, fish, shellfish and eggs. Due to this, vegetarians are at risk to develop a vitamin B12 deficiency and it is recommended that they consume fortified food. Vitamin B12 behaves differently to most vitamins of the B complex in several aspects, e.g. it is more stable, has a very specific mechanism of absorption and is stored in large amounts in the organism. This review summarises all its biological aspects (including its structure and natural sources as well as its stability in food, pharmacokinetics and physiological function) as well as causes, symptoms, diagnosis (with a summary of analytical methods for its measurement), prevention and treatment of its deficiency, and its pharmacological use and potential toxicity.
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Affiliation(s)
- Monika Moravcová
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Tomáš Siatka
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Lenka Kujovská Krčmová
- Department of Clinical Biochemistry and Diagnostics, University Hospital Hradec Králové, Hradec Králové, Czech Republic
- Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Kateřina Matoušová
- Department of Clinical Biochemistry and Diagnostics, University Hospital Hradec Králové, Hradec Králové, Czech Republic
| | - Přemysl Mladěnka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
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Crider KS, Qi YP, Yeung LF, Mai CT, Head Zauche L, Wang A, Daniels K, Williams JL. Folic Acid and the Prevention of Birth Defects: 30 Years of Opportunity and Controversies. Annu Rev Nutr 2022; 42:423-452. [PMID: 35995050 PMCID: PMC9875360 DOI: 10.1146/annurev-nutr-043020-091647] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
For three decades, the US Public Health Service has recommended that all persons capable of becoming pregnant consume 400 μg/day of folic acid (FA) to prevent neural tube defects (NTDs). The neural tube forms by 28 days after conception. Fortification can be an effective NTD prevention strategy in populations with limited access to folic acid foods and/or supplements. This review describes the status of mandatory FA fortification among countries that fortify (n = 71) and the research describing the impact of those programs on NTD rates (up to 78% reduction), blood folate concentrations [red blood cell folate concentrations increased ∼1.47-fold (95% CI, 1.27, 1.70) following fortification], and other health outcomes. Across settings, high-quality studies such as those with randomized exposures (e.g., randomized controlled trials, Mendelian randomization studies) are needed to elucidate interactions of FA with vitamin B12 as well as expanded biomarker testing.
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Affiliation(s)
- Krista S Crider
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | - Yan Ping Qi
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | - Lorraine F Yeung
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | - Cara T Mai
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | - Lauren Head Zauche
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
| | - Arick Wang
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | | | - Jennifer L Williams
- Neural Tube Defects Surveillance and Prevention Team, Infant Outcomes Monitoring, Research, and Prevention Branch, Division of Birth Defects and Infant Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
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Bortolus R, Filippini F, Cipriani S, Trevisanuto D, Cavallin F, Zanconato G, Somigliana E, Cesari E, Mastroiacovo P, Parazzini F. Efficacy of 4.0 mg versus 0.4 mg Folic Acid Supplementation on the Reproductive Outcomes: A Randomized Controlled Trial. Nutrients 2021; 13:nu13124422. [PMID: 34959975 PMCID: PMC8704306 DOI: 10.3390/nu13124422] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/04/2021] [Accepted: 12/08/2021] [Indexed: 01/13/2023] Open
Abstract
Folic acid (FA) supplementation prevents neural tube defects (NTDs), but the effects on other reproductive outcomes are unclear. While common recommendation is 0.4 mg/day in addition to regular nutrition, the most appropriate dose of FA is still under debate. We investigated the effects of a higher dose of periconception FA on reducing adverse reproductive outcomes. In this multicenter double-blind randomized controlled trial (RCT), 1060 women (aged 18-44 years and planning a pregnancy) were randomly assigned to receive 4.0 mg or 0.4 mg of FA daily. The primary outcome was the occurrence of congenital malformations (CMs). A composite outcome including one or more adverse pregnancy outcomes was also evaluated. A total of 431 women had a natural conception within 1 year. The primary outcome occurred in 8/227 (3.5%) women receiving 4.0 mg FA and 9/204 (4.4%) women receiving 0.4 mg FA (RR 0.80; 95%CI 0.31 to 2.03). The composite outcome occurred in 43/227 (18.9%) women receiving 4.0 mg FA and 75/204 (36.8%) women receiving 0.4 mg FA (RR 0.51; 95%CI 0.40 to 0.68). FA 4.0 mg supplementation was not associated with different occurrence of CMs, compared to FA 0.4 mg supplementation. However, FA 4.0 mg supplementation was associated with lower occurrence of other adverse pregnancy outcomes.
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Affiliation(s)
- Renata Bortolus
- Office for Research Promotion, Verona University Hospital, 37134 Verona, Italy; (R.B.); (F.F.)
| | - Francesca Filippini
- Office for Research Promotion, Verona University Hospital, 37134 Verona, Italy; (R.B.); (F.F.)
| | - Sonia Cipriani
- Department of Woman, Newborn and Child, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (S.C.); (E.S.)
| | - Daniele Trevisanuto
- Department of Woman’s and Child’s Health, University of Padua, 35128 Padova, Italy;
| | | | - Giovanni Zanconato
- Department of Surgery, Odontostomatology and Maternal and Child Health, University of Verona, 37134 Verona, Italy;
| | - Edgardo Somigliana
- Department of Woman, Newborn and Child, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (S.C.); (E.S.)
- Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy
| | - Elena Cesari
- Department of Obstetrics and Gynaecology, Sant’Antonio Abate Hospital, 21013 Gallarate, Italy;
| | | | - Fabio Parazzini
- Department of Woman, Newborn and Child, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (S.C.); (E.S.)
- Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy
- Correspondence:
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Carter B, Zenasni Z, Moat SJ, Hudson PR, Russell IT, McCaddon A. Plasma Methylmalonic Acid Concentration in Folic Acid-Supplemented Depressed Patients with Low or Marginal Vitamin B-12: A Randomized Trial. J Nutr 2021; 151:3738-3745. [PMID: 34510193 PMCID: PMC8643600 DOI: 10.1093/jn/nxab280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/29/2021] [Accepted: 08/02/2021] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Individuals with low serum vitamin B-12 and high serum folate have higher plasma concentrations of methylmalonic acid (MMA). Whether folic acid (FA) causes an increase in MMA is not known. OBJECTIVES We aimed to determine the impact of FA supplementation on plasma MMA concentration in people with low or marginal serum vitamin B-12. METHODS We conducted a multicenter double-blind placebo-controlled randomized trial of oral FA (5 mg/d for 12 wk) in middle-aged patients treated with antidepressant medication participating in the FoLATED (Folate Augmentation of Treatment-Evaluation for Depression) trial. Participants defined as having "low" serum vitamin B-12 (vitamin B-12 ≥150 and <220 ng/L) or "marginal" serum vitamin B-12 (vitamin B-12 ≥ 220 and <280 ng/L) were included. The primary outcome of this substudy was MMA at week 12. A mixed-effects linear regression was fitted and reported using the adjusted mean difference (aMD). RESULTS A total of 177 participants were included (85 randomly assigned to placebo and 92 to FA); the mean ± SD age was 46.2 ± 11.8 y, and 112 (63.3%) were female. The MMA analysis included 135 participants and the aMD was -0.01 (95% CI: -0.06, 0.04; P = 0.71). Serum folate was measured on 166 participants and increased in the supplementation group; the aMD was 21.6 μg/L (95% CI: 8.13, 25.02 μg/L; P < 0.001). A total of 117 participants were assessed for RBC folate, which also increased in the supplementation group; the aMD was 461 μg/L (95% CI: 387, 535 μg/L; P < 0.001). CONCLUSIONS Supplementation of FA leads to an increase of serum and RBC folate, but does not change plasma MMA concentration in individuals with serum vitamin B-12 between 150 and 280 ng/L. We cannot exclude effects in older people or those with serum vitamin B-12 <150 ng/L. Previously reported associations may arise from effects of impaired vitamin B-12 status on folate metabolism.This trial was registered at www.isrctn.com as ISRCTN37558856.
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Affiliation(s)
- Ben Carter
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Zohra Zenasni
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Stuart J Moat
- School of Medicine, Cardiff University, University Hospital of Wales, Cardiff, United Kingdom,Department of Medical Biochemistry and Immunology & Toxicology, Cardiff and Vale University Health Board, Cardiff, United Kingdom
| | | | - Ian T Russell
- Swansea Trials Unit, Swansea University Medical School, Swansea, United Kingdom
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Saldanha LG, Dwyer JT, Haggans CJ, Mills JL, Potischman N. Perspective: Time to Resolve Confusion on Folate Amounts, Units, and Forms in Prenatal Supplements. Adv Nutr 2020; 11:753-759. [PMID: 32134106 PMCID: PMC7360441 DOI: 10.1093/advances/nmaa017] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/01/2020] [Accepted: 02/05/2020] [Indexed: 12/26/2022] Open
Abstract
Folate-containing prenatal supplements are commonly consumed in the United States, but inconsistencies in units of measure and chemical forms pose challenges for providing authoritative advice on recommended amounts. New regulations require folate to be declared as micrograms of dietary folate equivalents (DFE) on product labels, whereas intake recommendations for reducing the risk of neural tube defects (NTDs) and the Tolerable Upper Intake Level are expressed as micrograms of folic acid. Today, >25% of prenatal supplements contain folate as synthetic salts of L-5-methyltetrahydrofolate (L-5-MTHF), but recommendations do not include this form of the vitamin. Harmonizing units of measure and addressing newer forms of folate salts in intake recommendations and in the prevention of NTDs would resolve the confusion.
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Affiliation(s)
- Leila G Saldanha
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD, USA
| | - Johanna T Dwyer
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD, USA
| | - Carol J Haggans
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD, USA
| | - James L Mills
- Epidemiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Nancy Potischman
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD, USA
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6
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Wang B, Sahyoun NR, Shao K, Dutta E, Clarke J. Assessment of the Dose-Response Relationship Between Folate Exposure and Cognitive Impairment: Synthesizing Data from Documented Studies. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2020; 40:276-293. [PMID: 31536147 DOI: 10.1111/risa.13404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/09/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
The dose-response relationship between folate levels and cognitive impairment among individuals with vitamin B12 deficiency is an essential component of a risk-benefit analysis approach to regulatory and policy recommendations regarding folic acid fortification. Epidemiological studies provide data that are potentially useful for addressing this research question, but the lack of analysis and reporting of data in a manner suitable for dose-response purposes hinders the application of the traditional evidence synthesis process. This study aimed to estimate a quantitative dose-response relationship between folate exposure and the risk of cognitive impairment among older adults with vitamin B12 deficiency using "probabilistic meta-analysis," a novel approach for synthesizing data from observational studies. Second-order multistage regression was identified as the best-fit model for the association between the probability of cognitive impairment and serum folate levels based on data generated by randomly sampling probabilistic distributions with parameters estimated based on summarized information reported in relevant publications. The findings indicate a "J-shape" effect of serum folate levels on the occurrence of cognitive impairment. In particular, an excessive level of folate exposure is predicted to be associated with a higher risk of cognitive impairment, albeit with greater uncertainty than the association between low folate exposure and cognitive impairment. This study directly contributes to the development of a practical solution to synthesize observational evidence for dose-response assessment purposes, which will help strengthen future nutritional risk assessments for the purpose of informing decisions on nutrient fortification in food.
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Affiliation(s)
- Bing Wang
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Nadine R Sahyoun
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
| | - Kan Shao
- Department of Environmental and Occupational Health, Indiana University, Bloomington, IN, USA
| | - Enakshy Dutta
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Jennifer Clarke
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE, USA
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7
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Berry RJ. Lack of historical evidence to support folic acid exacerbation of the neuropathy caused by vitamin B12 deficiency. Am J Clin Nutr 2019; 110:554-561. [PMID: 31187858 PMCID: PMC6785032 DOI: 10.1093/ajcn/nqz089] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/17/2019] [Indexed: 12/22/2022] Open
Abstract
In 1998 a Tolerable Upper Intake Level (UL) for folic acid was established based on case reports from the 1940s suggesting that high-dosage folic acid intake, used to treat patients with pernicious anemia, had the potential to precipitate or speed-up the development of neurological problems. This UL has been employed in the decision-making process used by more than 80 countries to establish programs to fortify staple foods with folic acid to prevent neural tube birth defects. Some have claimed that this UL is flawed and has become an obstacle to the wider adoption of neural tube defect prevention programs and have called for re-evaluation of the scientific validity of this UL. Case reports cannot establish causality, but they can reveal patterns in the timing of the onset and treatment of patients with pernicious anemia. These patterns can be compared with secular trends of usual medical practice for the treatment of pernicious anemia and with the changes in usage of folic acid preparations, including recommended therapeutic dosage and precautions for its usage surrounding the synthesis of folic acid in 1945 and vitamin B12 in 1948. Folic acid package inserts, early editions of hematology textbooks, and international expert reports provide valuable historical information. The recommended therapeutic daily dosage for folic acid of 5-20 mg was unchanged from 1946 through to 1971. The likely cause of the neurological problems encountered is the development of vitamin B12 neuropathy when pernicious anemia was treated with high-dosage folic acid before vitamin B12 was widely available in the early 1950s. Thus, the historical record does not provide compelling evidence that folic acid can potentially cause neurologic complications among those with low vitamin B12 status and lends support for reconsidering the basis for the UL of folic acid.
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Affiliation(s)
- Robert J Berry
- Centers for Disease Control and Prevention, National Center on Birth Defects and Developmental Disabilities, Division of Congenital and Developmental Disorders, Atlanta, GA
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Centeno Tablante E, Pachón H, Guetterman HM, Finkelstein JL. Fortification of wheat and maize flour with folic acid for population health outcomes. Cochrane Database Syst Rev 2019; 7:CD012150. [PMID: 31257574 PMCID: PMC6599881 DOI: 10.1002/14651858.cd012150.pub2] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Folate is a B-vitamin required for DNA synthesis, methylation, and cellular division. Wheat and maize (corn) flour are staple crops consumed widely throughout the world and have been fortified with folic acid in over 80 countries to prevent neural tube defects. Folic acid fortification may be an effective strategy to improve folate status and other health outcomes in the overall population. OBJECTIVES To evaluate the health benefits and safety of folic acid fortification of wheat and maize flour (i.e. alone or in combination with other micronutrients) on folate status and health outcomes in the overall population, compared to wheat or maize flour without folic acid (or no intervention). SEARCH METHODS We searched the following databases in March and May 2018: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and MEDLINE In Process, Embase, CINAHL, Web of Science (SSCI, SCI), BIOSIS, Popline, Bibliomap, TRoPHI, ASSIA, IBECS, SCIELO, Global Index Medicus-AFRO and EMRO, LILACS, PAHO, WHOLIS, WPRO, IMSEAR, IndMED, and Native Health Research Database. We searched the International Clinical Trials Registry Platform and ClinicalTrials.gov for ongoing or planned studies in June 2018, and contacted authors for further information. SELECTION CRITERIA We included randomised controlled trials (RCTs), with randomisation at the individual or cluster level. We also included non-RCTs and prospective observational studies with a control group; these studies were not included in meta-analyses, although their characteristics and findings were described. Interventions included wheat or maize flour fortified with folic acid (i.e. alone or in combination with other micronutrients), compared to unfortified flour (or no intervention). Participants were individuals over two years of age (including pregnant and lactating women), from any country. DATA COLLECTION AND ANALYSIS Two review authors independently assessed study eligibility, extracted data, and assessed risk of bias. MAIN RESULTS We included 10 studies: four provided data for quantitative analyses (437 participants); five studies were randomised trials (1182 participants); three studies were non-RCTs (1181 participants, 8037 live births); two studies were interrupted time series (ITS) studies (1 study population of 2,242,438, 1 study unreported). Six studies were conducted in upper-middle-income countries (China, Mexico, South Africa), one study was conducted in a lower-middle-income country (Bangladesh), and three studies were conducted in a high-income country (Canada). Seven studies examined wheat flour fortified with folic acid alone or with other micronutrients. Three studies included maize flour fortified with folic acid alone or with other micronutrients. The duration of interventions ranged from two weeks to 36 months, and the ITS studies included postfortification periods of up to seven years. Most studies had unclear risk of bias for randomisation, blinding, and reporting, and low/unclear risk of bias for attrition and contamination.Neural tube defects: none of the included RCTs reported neural tube defects as an outcome. In one non-RCT, wheat flour fortified with folic acid and other micronutrients was associated with significantly lower occurrence of total neural tube defects, spina bifida, and encephalocoele, but not anencephaly, compared to unfortified flour (total neural tube defects risk ratio (RR) 0.32, 95% confidence interval (CI) 0.21 to 0.48; 1 study, 8037 births; low-certainty evidence).Folate status: pregnant women who received folic acid-fortified maize porridge had significantly higher erythrocyte folate concentrations (mean difference (MD) 238.90 nmol/L, 95% CI 149.40 to 328.40); 1 study, 38 participants; very low-certainty evidence) and higher plasma folate (MD 14.98 nmol/L, 95% CI 9.63 to 20.33; 1 study, 38 participants; very low-certainty evidence), compared to no intervention. Women of reproductive age consuming maize flour fortified with folic acid and other micronutrients did not have higher erythrocyte folate (MD -61.80 nmol/L, 95% CI -152.98 to 29.38; 1 study, 35 participants; very low-certainty evidence) or plasma folate (MD 0.00 nmol/L, 95% CI -0.00 to 0.00; 1 study, 35 participants; very low-certainty evidence) concentrations, compared to women consuming unfortified maize flour. Adults consuming folic acid-fortified wheat flour bread rolls had higher erythrocyte folate (MD 0.66 nmol/L, 95% CI 0.13 to 1.19; 1 study, 30 participants; very low-certainty evidence) and plasma folate (MD 27.00 nmol/L, 95% CI 15.63 to 38.37; 1 study, 30 participants; very low-certainty evidence), versus unfortified flour. In two non-RCTs, serum folate concentrations were significantly higher among women who consumed flour fortified with folic acid and other micronutrients compared to women who consumed unfortified flour (MD 2.92 nmol/L, 95% CI 1.99 to 3.85; 2 studies, 657 participants; very low-certainty evidence).Haemoglobin or anaemia: in a cluster-randomised trial among children, there were no significant effects of fortified wheat flour flatbread on haemoglobin concentrations (MD 0.00 nmol/L, 95% CI -2.08 to 2.08; 1 study, 334 participants; low-certainty evidence) or anaemia (RR 1.07, 95% CI 0.74 to 1.55; 1 study, 334 participants; low-certainty evidence), compared to unfortified wheat flour flatbread. AUTHORS' CONCLUSIONS Fortification of wheat flour with folic acid may reduce the risk of neural tube defects; however, this outcome was only reported in one non-RCT. Fortification of wheat or maize flour with folic acid (i.e. alone or with other micronutrients) may increase erythrocyte and serum/plasma folate concentrations. Evidence is limited for the effects of folic acid-fortified wheat or maize flour on haemoglobin levels or anaemia. The effects of folic acid fortification of wheat or maize flour on other primary outcomes assessed in this review is not known. No studies reported on the occurrence of adverse effects. Limitations of this review were the small number of studies and participants, limitations in study design, and low-certainty of evidence due to how included studies were designed and reported.
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Affiliation(s)
| | - Helena Pachón
- Food Fortification Initiative & Emory University1518 Clifton Rd NE, Room 2049AtlantaGeorgiaUSA
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9
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Mills JL, Dimopoulos A, Bailey RL. What is standing in the way of complete prevention of folate preventable neural tube defects? ACTA ACUST UNITED AC 2018; 106:517-9. [PMID: 27418028 DOI: 10.1002/bdra.23518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 04/07/2016] [Indexed: 01/21/2023]
Affiliation(s)
- James L Mills
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Aggeliki Dimopoulos
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Regan L Bailey
- Department of Nutrition Science, Purdue University, West Lafayette, Indiana
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Kaur L, Puri M, Saraswathy KN, Trivedi SS, Sachdeva MP. Recurrent pregnancy losses vis-à-vis anemia and vitamin (Folate/B12) imbalance. INTERNATIONAL JOURNAL OF HEALTH GOVERNANCE 2018. [DOI: 10.1108/ijhg-05-2018-0018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Purpose
Recurrent pregnancy losses (RPL), a major contributor of reproductive wastage, affect maternal health both physically and mentally. Folate and B12 (Vitamin B12) deficiency anemia is common in the reproductive age group women in developing countries like India. And due to proven role of folate in various maternal and fetal anomalies, women are routinely prescribed folic acid under various national policies. However, B12 supplementation is rare, despite known deleterious effects of its deficiency. The purpose of this paper is to understand RPL through anemia with special reference to folate and B12 imbalance.
Design/methodology/approach
Multiparous women with normal obstetric outcomes (n=135) and women with Idiopathic RPL (n=105) were recruited in the study. All women were non-pregnant and belonged to North Indian population. Hb, serum folate and B12 and plasma homocysteine were measured in all the women. Anemia was classified according to WHO guidelines (Hemoglobin (Hb)<12g/dL).
Findings
The incidence of Anemia was more among normal multiparous women (73 percent) as compared to women with RPL (60 percent). However, unlike folate deficiency anemia among controls, B12 deficiency anemia was observed in women with RPL. Moreover, these women, despite being less anemic, with high B12 deficiency and folate sufficiency (presumably due to folate supplementation) had more imbalanced vitamin metabolism, as evident from homocysteine levels. The study suggests that anemic or non-anemic deficiencies of B12 and folate among women with RPL may be combated by screening for both vitamins, rather than supplementing folate indiscriminately to all.
Research limitations/implications
One of the limitations is that ferritin levels for iron deficiency anemia could not be measured in this study.
Originality/value
The present study is the first study, to the best of our knowledge, where we looked for the role of imbalance of folate and B12 in women with RPL.
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Mills JL, Molloy AM, Reynolds EH. Do the benefits of folic acid fortification outweigh the risk of masking vitamin B 12 deficiency? BMJ 2018; 360:k724. [PMID: 29496696 PMCID: PMC6889897 DOI: 10.1136/bmj.k724] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adding folate to cereals can prevent neural tube defects and other health problems, say James Mills and Anne Molloy, but Edward Reynolds is concerned that prolonged excessive folate risks harm unless vitamin B12 is also supplemented
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Affiliation(s)
- James L Mills
- Epidemiology Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
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12
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Arias LD, Parra BE, Muñoz AM, Cárdenas DL, Duque TG, Manjarrés LM. Study Exploring the Effects of Daily Supplementation with 400 μg of Folic Acid on the Nutritional Status of Folate in Women of Reproductive Age. Birth Defects Res 2017; 109:564-573. [PMID: 28398657 DOI: 10.1002/bdr2.1004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 12/19/2016] [Accepted: 12/28/2016] [Indexed: 11/08/2022]
Abstract
BACKGROUND This investigation determines the nutritional state of serum and red blood cell (RBC) folate concentration and their relation with intake of folate, B6 ,and B12 , with serum vitamin B12 , and with genetic variants after provision of 400 μg/day of folic acid for 3 months to a group of 34 Colombian women of reproductive age. METHODS We evaluated nutrient intake using 24-hr recall, assessing the levels of serum folate, RBC folate, serum B12 , and homocysteine, as well as determining genetic variants of the enzyme MTHFR (C677T and A1298C) and CβS (844ins68pb). RESULTS The results show that following intake of 400 μg/day of folic acid, the risk of folate deficiency as seen in regular dietary intake disappears and the nutritional status of this nutrient is increased (p < 0.001). With respect to vitamin B12, the risk of serum deficiency with folic acid consumption increased slightly, and those that were found to be B12 deficient after supplementation also had decreased levels of serum homocysteine. Genetic factors did not influence the nutritional status of folate, although an association was found between the intake of nutrients and biochemical indicators. CONCLUSION Given the results of our study, subsequent studies evaluating folic acid supplementation should also consider evaluating the status of B12 and B6 , and serum and RBC folate, as they participate interdependently in the cycle of folate and methionine and in homocysteine metabolism.Birth Defects Research 109:564-573, 2017.© 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Laidy D Arias
- Research Group in Food and Human Nutrition, School of Nutrition and Dietetics, Universidad de Antioquia, Medellín, Colombia
| | - Beatriz E Parra
- Research Group in Food and Human Nutrition, School of Nutrition and Dietetics, Universidad de Antioquia, Medellín, Colombia
| | - Angélica M Muñoz
- Research Group in Food and Human Nutrition, School of Nutrition and Dietetics, Universidad de Antioquia, Medellín, Colombia
| | - Diana L Cárdenas
- Research Group in Food and Human Nutrition, School of Nutrition and Dietetics, Universidad de Antioquia, Medellín, Colombia
| | | | - Luz M Manjarrés
- Research Group in Food and Human Nutrition, School of Nutrition and Dietetics, Universidad de Antioquia, Medellín, Colombia
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Vitamin B 12 deficiency from the perspective of a practicing hematologist. Blood 2017; 129:2603-2611. [PMID: 28360040 DOI: 10.1182/blood-2016-10-569186] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 03/20/2017] [Indexed: 02/07/2023] Open
Abstract
B12 deficiency is the leading cause of megaloblastic anemia, and although more common in the elderly, can occur at any age. Clinical disease caused by B12 deficiency usually connotes severe deficiency, resulting from a failure of the gastric or ileal phase of physiological B12 absorption, best exemplified by the autoimmune disease pernicious anemia. There are many other causes of B12 deficiency, which range from severe to mild. Mild deficiency usually results from failure to render food B12 bioavailable or from dietary inadequacy. Although rarely resulting in megaloblastic anemia, mild deficiency may be associated with neurocognitive and other consequences. B12 deficiency is best diagnosed using a combination of tests because none alone is completely reliable. The features of B12 deficiency are variable and may be atypical. Timely diagnosis is important, and treatment is gratifying. Failure to diagnose B12 deficiency can have dire consequences, usually neurological. This review is written from the perspective of a practicing hematologist.
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Paul L, Selhub J. Interaction between excess folate and low vitamin B12 status. Mol Aspects Med 2016; 53:43-47. [PMID: 27876554 DOI: 10.1016/j.mam.2016.11.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/18/2016] [Indexed: 01/05/2023]
Abstract
Current epidemiological evidence suggests that an imbalance of high folate status and low vitamin B12 status is associated with negative health outcomes in older adults and children. Such an imbalance during pregnancy also predisposes women to diabetes and their offspring to insulin resistance and adiposity and low birthweight. In older adults, vitamin B12 status can remain low despite adequate intake due to age-related decline in vitamin B12 absorption. Pregnant women are exposed to folic acid at varying doses depending on the prenatal care prescribed in different countries. This review summarizes the current knowledge on the interaction between folate and vitamin B12 and the associated health outcomes.
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Affiliation(s)
- Ligi Paul
- Jean Mayer USDA Human Nutrition Research Center for Aging at Tufts University, Boston, MA, 02111, USA.
| | - Jacob Selhub
- Jean Mayer USDA Human Nutrition Research Center for Aging at Tufts University, Boston, MA, 02111, USA
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Porter K, Hoey L, Hughes CF, Ward M, McNulty H. Causes, Consequences and Public Health Implications of Low B-Vitamin Status in Ageing. Nutrients 2016; 8:E725. [PMID: 27854316 PMCID: PMC5133110 DOI: 10.3390/nu8110725] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 10/26/2016] [Accepted: 11/09/2016] [Indexed: 12/11/2022] Open
Abstract
The potential protective roles of folate and the metabolically related B-vitamins (vitamins B12, B6 and riboflavin) in diseases of ageing are of increasing research interest. The most common cause of folate and riboflavin deficiencies in older people is low dietary intake, whereas low B12 status is primarily associated with food-bound malabsorption, while sub-optimal vitamin B6 status is attributed to increased requirements in ageing. Observational evidence links low status of folate and the related B-vitamins (and/or elevated concentrations of homocysteine) with a higher risk of degenerative diseases including cardiovascular disease (CVD), cognitive dysfunction and osteoporosis. Deficient or low status of these B-vitamins alone or in combination with genetic polymorphisms, including the common MTHFR 677 C → T polymorphism, could contribute to greater disease risk in ageing by causing perturbations in one carbon metabolism. Moreover, interventions with the relevant B-vitamins to optimise status may have beneficial effects in preventing degenerative diseases. The precise mechanisms are unknown but many have been proposed involving the role of folate and the related B-vitamins as co-factors for one-carbon transfer reactions, which are fundamental for DNA and RNA biosynthesis and the maintenance of methylation reactions. This review will examine the evidence linking folate and related B-vitamins with health and disease in ageing, associated mechanisms and public health implications.
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Affiliation(s)
- Kirsty Porter
- Northern Ireland Centre for Food and Health, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Leane Hoey
- Northern Ireland Centre for Food and Health, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Catherine F Hughes
- Northern Ireland Centre for Food and Health, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Mary Ward
- Northern Ireland Centre for Food and Health, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Helene McNulty
- Northern Ireland Centre for Food and Health, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
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Ami N, Bernstein M, Boucher F, Rieder M, Parker L. Folate and neural tube defects: The role of supplements and food fortification. Paediatr Child Health 2016; 21:145-54. [PMID: 27398055 DOI: 10.1093/pch/21.3.145] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Periconceptional folic acid significantly reduces the risk of neural tube defects. It is difficult to achieve optimal levels of folate by diet alone, even with fortification of flour, especially because flour consumption in Canada is slightly decreasing. Intermittent concerns have been raised concerning possible deleterious effects of folate supplementation, including the masking of symptoms of vitamin B12 deficiency and an association with cancer, especially colorectal cancer. Both concerns have been disproved. The Canadian Paediatric Society endorses the following steps to enhance folate intake in women of child-bearing age: encouraging the consumption of folate-rich foods such as leafy vegetables, increasing the level of folate food fortification, taking a supplement containing folate and B12, and providing free folate supplementation to disadvantaged women of child-bearing age. These recommendations are consistent with those of the Society of Obstetricians and Gynaecologists of Canada.
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17
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Walker D. Fortification of flour with folic acid is an overdue public health measure in the UK. Arch Dis Child 2016; 101:593. [PMID: 26933152 DOI: 10.1136/archdischild-2015-309983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/14/2016] [Indexed: 11/03/2022]
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18
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Ami N, Bernstein M, Boucher F, Rieder M, Parker L. Le folate et les anomalies du tube neural : le rôle des suppléments et des aliments enrichis. Paediatr Child Health 2016. [DOI: 10.1093/pch/21.3.150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Affiliation(s)
- James L Mills
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
| | - Aggeliki Dimopoulos
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
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20
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Bortolus R, Blom F, Filippini F, van Poppel MNM, Leoncini E, de Smit DJ, Benetollo PP, Cornel MC, de Walle HEK, Mastroiacovo P. Prevention of congenital malformations and other adverse pregnancy outcomes with 4.0 mg of folic acid: community-based randomized clinical trial in Italy and the Netherlands. BMC Pregnancy Childbirth 2014; 14:166. [PMID: 24884885 PMCID: PMC4045958 DOI: 10.1186/1471-2393-14-166] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 04/25/2014] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND In 2010 a Cochrane review confirmed that folic acid (FA) supplementation prevents the first- and second-time occurrence of neural tube defects (NTDs). At present some evidence from observational studies supports the hypothesis that FA supplementation can reduce the risk of all congenital malformations (CMs) or the risk of a specific and selected group of them, namely cardiac defects and oral clefts. Furthermore, the effects on the prevention of prematurity, foetal growth retardation and pre-eclampsia are unclear.Although the most common recommendation is to take 0.4 mg/day, the problem of the most appropriate dose of FA is still open.The aim of this project is to assess the effect a higher dose of peri-conceptional FA supplementation on reducing the occurrence of all CMs. Other aims include the promotion of pre-conceptional counselling, comparing rates of selected CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age, abruptio placentae. METHODS/DESIGN This project is a joint effort by research groups in Italy and the Netherlands. Women of childbearing age, who intend to become pregnant within 12 months are eligible for the studies. Women are randomly assigned to receive 4 mg of FA (treatment in study) or 0.4 mg of FA (referent treatment) daily. Information on pregnancy outcomes are derived from women-and-physician information.We foresee to analyze the data considering all the adverse outcomes of pregnancy taken together in a global end point (e.g.: CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age). A total of about 1,000 pregnancies need to be evaluated to detect an absolute reduction of the frequency of 8%. Since the sample size needed for studying outcomes separately is large, this project also promotes an international prospective meta-analysis. DISCUSSION The rationale of these randomized clinical trials (RCTs) is the hypothesis that a higher intake of FA is related to a higher risk reduction of NTDs, other CMs and other adverse pregnancy outcomes. Our hope is that these trials will act as catalysers, and lead to other large RCTs studying the effects of this supplementation on CMs and other infant and maternal outcomes. TRIAL REGISTRATION Italian trial: ClinicalTrials.gov Identifier: NCT01244347.Dutch trial: Dutch Trial Register ID: NTR3161.
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Affiliation(s)
- Renata Bortolus
- Office for Research Promotion, Department of the Hospital Management and Pharmacy, Verona University Hospital, P.le A. Stefani, 1-37126 Verona, Italy
| | - Fenneke Blom
- Community Genetics, Department of Clinical Genetics, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Francesca Filippini
- Office for Research Promotion, Department of the Hospital Management and Pharmacy, Verona University Hospital, P.le A. Stefani, 1-37126 Verona, Italy
| | - Mireille NM van Poppel
- Department of Public and Occupational Health, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Emanuele Leoncini
- Alessandra Lisi International Centre on Birth Defects and Prematurity-ICBD, WHO Collaborating Centre, Rome, Italy
| | | | | | - Martina C Cornel
- Community Genetics, Department of Clinical Genetics, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Hermien EK de Walle
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Pierpaolo Mastroiacovo
- Alessandra Lisi International Centre on Birth Defects and Prematurity-ICBD, WHO Collaborating Centre, Rome, Italy
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21
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Blancquaert D, De Steur H, Gellynck X, Van Der Straeten D. Present and future of folate biofortification of crop plants. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:895-906. [PMID: 24574483 DOI: 10.1093/jxb/ert483] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Improving nutritional health is one of the major socio-economic challenges of the 21st century, especially with the continuously growing and ageing world population. Folate deficiency is an important and underestimated problem of micronutrient malnutrition affecting billions of people worldwide. More and more countries are adapting policies to fight folate deficiency, mostly by fortifying foods with folic acid. However, there is growing concern about this practice, calling for alternative or complementary strategies. In addition, fortification programmes are often inaccessible to remote and poor populations where folate deficiency is most prevalent. Enhancing folate content in staple crops by metabolic engineering is a promising, cost-effective strategy to eradicate folate malnutrition worldwide. Over the last decade, major progress has been made in this field. Nevertheless, engineering strategies have thus far been implemented on a handful of plant species only and need to be transferred to highly consumed staple crops to maximally reach target populations. Moreover, successful engineering strategies appear to be species-dependent, hence the need to adapt them in order to biofortify different staple crops with folate.
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Affiliation(s)
- Dieter Blancquaert
- Laboratory of Functional Plant Biology, Department of Physiology, Ghent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium
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22
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Qi YP, Do AN, Hamner HC, Pfeiffer CM, Berry RJ. The prevalence of low serum vitamin B-12 status in the absence of anemia or macrocytosis did not increase among older U.S. adults after mandatory folic acid fortification. J Nutr 2014; 144:170-6. [PMID: 24306216 PMCID: PMC5291239 DOI: 10.3945/jn.113.183095] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Whether folic acid fortification and supplementation at the population level have led to a higher prevalence of vitamin B-12 deficiency in the absence of anemia remains to be examined among a nationally representative sample of older U.S. adults. We assessed the prevalence of low vitamin B-12 status in the absence of anemia or macrocytosis before and after fortification among adults aged >50 y using cross-sectional data from the NHANES 1991-1994 (prefortification) and 2001-2006 (postfortification). We compared the prefortification and postfortification prevalence of multiple outcomes, including serum vitamin B-12 deficiency (<148 pmol/L) and marginal deficiency (148-258 pmol/L) with and without anemia (hemoglobin <130 g/L for men, <120 g/L for women) and with and without macrocytosis (mean cell volume >100 fL) using multinomial logistic regression, adjusting for age, sex, ethnicity, body mass index, C-reactive protein, and vitamin B-12 supplement use. Prefortification and postfortification serum vitamin B-12 deficiency without anemia [4.0 vs. 3.9%; adjusted prevalence ratio (aPR) (95% CI): 0.98 (0.67, 1.44)] or without macrocytosis [4.2 vs. 4.1%; aPR (95% CI): 0.96 (0.65, 1.43)] remained unchanged. Marginal deficiency without anemia [25.1 vs. 20.7%; aPR (95% CI): 0.82 (0.72, 0.95)] or without macrocytosis [25.9 vs. 21.3%; aPR (95% CI): 0.82 (0.72, 0.94)] were both significantly lower after fortification. After fortification, higher folic acid intake was associated with a lower prevalence of low serum B-12 status in the absence of anemia or macrocytosis. Results suggest that the prevalence of low serum B-12 status in the absence of anemia or macrocytosis among older U.S. adults did not increase after fortification. Thus, at the population level, we found no evidence to support concerns that folic acid adversely affected the clinical presentation of vitamin B-12 deficiency among older adults.
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Affiliation(s)
- Yan Ping Qi
- Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Atlanta, GA,To whom correspondence should be addressed.
| | - Ann N. Do
- Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Atlanta, GA
| | - Heather C. Hamner
- Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Atlanta, GA
| | - Christine M. Pfeiffer
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA
| | - Robert J. Berry
- Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Atlanta, GA
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Abstract
Optimal functioning of the central and peripheral nervous system is dependent on a constant supply of appropriate nutrients. Particularly important for optimal functioning of the nervous system is cobalamin (vitamin B12). Cobalamin deficiency is particularly common in the elderly and after gastric surgery. Many patients with clinically expressed cobalamin deficiency have intrinsic factor-related malabsorption such as that seen in pernicious anemia. The commonly recognized neurological manifestations of cobalamin deficiency include a myelopathy with or without an associated neuropathy. This review deals with neurological aspects of vitamin B12 deficiency and attempts to highlight recent developments.
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Affiliation(s)
- Neeraj Kumar
- Department of Neurology, Mayo Clinic, Rochester, MN, USA.
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24
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Abstract
John Scott (1940-2013) was born in Dublin where he was to spend the rest of his career, both as an undergraduate and subsequently Professor of Biochemistry and Nutrition at Trinity College. His research with the talented group of scientists and clinicians that he led has had a substantial impact on our understanding of folate metabolism, mechanisms of its catabolism and deficiency. His research established the leading theory of folate involvement with vitamin B12 in the pathogenesis of vitamin B12 neuropathy. He helped to establish the normal daily intake of folate and the increased requirements needed either in food or as a supplement before and during pregnancy to prevent neural tube defects. He also suggested a dietary supplement of vitamin B12 before and during pregnancy to reduce the risk of neural tube defects. It would be an appropriate epitaph if fortification of food with folic acid became mandatory in the UK and Ireland, as it is in over 70 other countries.
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Affiliation(s)
- A Victor Hoffbrand
- Emeritus Professor of Haematology, University College London, London, UK; Honorary Consultant Haematologist, Royal Free Hospital, London, UK
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25
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Hughes CF, Ward M, Hoey L, McNulty H. Vitamin B12 and ageing: current issues and interaction with folate. Ann Clin Biochem 2013; 50:315-29. [DOI: 10.1177/0004563212473279] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A compromised vitamin B12 status is common in older people despite dietary intakes that typically far exceed current recommendations. The maintenance of an optimal status of vitamin B12 is not only dependent on adequate dietary intake but more critically on effective absorption which diminishes with age. The measurement of vitamin B12 is complicated by the lack of a gold standard assay. There are a number of direct and functional indicators of vitamin B12 status; however, none of these are without limitations and should be used in combination. Vitamin B12 is of public health importance, not only because deficiency leads to megaloblastic anaemia and irreversible nerve damage, but also because emerging evidence links low B12 to an increased risk of a number of age-related diseases, including cardiovascular disease, cognitive dysfunction, dementia and osteoporosis. Furthermore, there are concerns relating to potential adverse effects for older adults with low vitamin B12 status of over-exposure to folic acid in countries where there is mandatory fortification of food with folic acid. The aim of this review is to examine the known and emerging issues related to vitamin B12 in ageing, its assessment and inter-relationship with folate.
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Affiliation(s)
- Catherine F Hughes
- The Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK
| | - Mary Ward
- The Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK
| | - Leane Hoey
- The Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK
| | - Helene McNulty
- The Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK
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Pachón H, Kancherla V, Handforth B, Tyler V, Bauwens L. Folic acid fortification of wheat flour: A cost-effective public health intervention to prevent birth defects in Europe. NUTR BULL 2013. [DOI: 10.1111/nbu.12023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - V. Kancherla
- Department of Epidemiology; Emory University; Atlanta; USA
| | | | | | - L. Bauwens
- International Federation for Spina Bifida and Hydrocephalus; Brussels; Belgium
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Rabovskaja V, Parkinson B, Goodall S. The cost-effectiveness of mandatory folic acid fortification in Australia. J Nutr 2013; 143:59-66. [PMID: 23223683 DOI: 10.3945/jn.112.166694] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The Australian government recently introduced mandatory folic acid fortification of bread to reduce the incidence of neural tube defects (NTDs). The economic evaluation of this policy contained a number of limitations. This study aimed to address the limitations and to reconsider the findings. Cost-effectiveness analysis was used to assess the cost and benefits of mandatory versus voluntary folic acid fortification. Outcomes measures were quality-adjusted life-years (QALYs), life-years gained (LYG), avoided NTD cases, and additional severe neuropathy cases. Costs considered included industry costs and regulatory costs to the government. It was estimated that mandatory fortification would prevent 31 NTDs, whereas an additional 14 cases of severe neuropathy would be incurred. Overall, 539 LYG and 503 QALYs would be gained per year of mandatory compared with voluntary fortification. Mandatory fortification was cost-effective at A$10,723 per LYG and at A$11,485 per QALY. Probabilistic sensitivity analysis showed that at A$60,000 and A$151,000 per QALY, the probability that mandatory fortification was the most cost-effective strategy was 79% and 85%, respectively. Threshold analysis of loss of consumer choice indicated that with a compensation value above A$1.21 [assuming a willingness to pay (WTP) threshold of A$60,000 per QALY] or A$3.19 (assuming a WTP threshold of A$151,000 per statistical life-year) per capita per year mandatory fortification would not be cost-effective. Mandatory fortification was found to be cost-effective; however, inclusion of the loss of consumer choice can change this result. Even with mandatory fortification, mean folate intake will remain below the recommended NTD preventive level.
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Affiliation(s)
- Viktoria Rabovskaja
- Centre for Health Economics Research and Evaluation, University of Technology, Sydney, Australia.
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Fajardo V, Alonso-Aperte E, Varela-Moreiras G. Lack of data on folate in convenience foods: Should ready-to-eat products be considered relevant for folate intake? The European challenge. J Food Compost Anal 2012. [DOI: 10.1016/j.jfca.2012.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Wehby GL, Goco N, Moretti-Ferreira D, Felix T, Richieri-Costa A, Padovani C, Queiros F, Guimaraes CVN, Pereira R, Litavecz S, Hartwell T, Chakraborty H, Javois L, Murray JC. Oral cleft prevention program (OCPP). BMC Pediatr 2012. [PMID: 23181832 PMCID: PMC3532199 DOI: 10.1186/1471-2431-12-184] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Oral clefts are one of the most common birth defects with significant medical, psychosocial, and economic ramifications. Oral clefts have a complex etiology with genetic and environmental risk factors. There are suggestive results for decreased risks of cleft occurrence and recurrence with folic acid supplements taken at preconception and during pregnancy with a stronger evidence for higher than lower doses in preventing recurrence. Yet previous studies have suffered from considerable design limitations particularly non-randomization into treatment. There is also well-documented effectiveness for folic acid in preventing neural tube defect occurrence at 0.4 mg and recurrence with 4 mg. Given the substantial burden of clefting on the individual and the family and the supportive data for the effectiveness of folic acid supplementation as well as its low cost, a randomized clinical trial of the effectiveness of high versus low dose folic acid for prevention of cleft recurrence is warranted. Methods/design This study will assess the effect of 4 mg and 0.4 mg doses of folic acid, taken on a daily basis during preconception and up to 3 months of pregnancy by women who are at risk of having a child with nonsyndromic cleft lip with/without palate (NSCL/P), on the recurrence of NSCL/P. The total sample will include about 6,000 women (that either have NSCL/P or that have at least one child with NSCL/P) randomly assigned to the 4 mg and the 0.4 mg folic acid study groups. The study will also compare the recurrence rates of NSCL/P in the total sample of subjects, as well as the two study groups (4mg, 0.4 mg) to that of a historical control group. The study has been approved by IRBs (ethics committees) of all involved sites. Results will be disseminated through publications and presentations at scientific meetings. Discussion The costs related to oral clefts are high, including long term psychological and socio-economic effects. This study provides an opportunity for huge savings in not only money but the overall quality of life. This may help establish more specific clinical guidelines for oral cleft prevention so that the intervention can be better tailored for at-risk women. ClinicalTrials.gov Identifier NCT00397917
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Bower C. Mandatory fortification of flour with folic acid to prevent neural-tube defects. ACTA ACUST UNITED AC 2012; 3:309-14. [PMID: 19803989 DOI: 10.2217/17455057.3.3.309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Firm evidence from randomized, controlled trials that maternal periconceptional folic acid reduced the risk of neural-tube defects was published in the early 1990s. Despite promotion of periconceptional folic acid supplement use, no more than 50% of women take them and so mandatory fortification of a staple food has been considered by many countries as an important adjunct to any public-health approach for the prevention of neural-tube defects. Even 15 years after the confirming evidence, some countries have yet to commit to mandatory fortification and, in those that have, there is limited and poorly coordinated monitoring and evaluation of its effectiveness and safety.
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Affiliation(s)
- Carol Bower
- Telethon Institute for Child Health Research, Centre for Child Health Research, The University of Western Australia, PO Box 855, West Perth, Western Australia 6874, Australia.
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Rapkin RB, Creinin MD. The combined oral contraceptive pill containing drospirenone and ethinyl estradiol plus levomefolate calcium. Expert Opin Pharmacother 2011; 12:2403-10. [DOI: 10.1517/14656566.2011.610791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Fleischman AR, Oinuma M. Fortification of corn masa flour with folic acid in the United States. Am J Public Health 2011; 101:1360-4. [PMID: 21680940 PMCID: PMC3134499 DOI: 10.2105/ajph.2011.300135] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2011] [Indexed: 11/04/2022]
Abstract
Food fortification is an effective public health tool for addressing micronutrient deficiencies. The mandatory fortification of enriched cereal grains (e.g., wheat flour) with folic acid, which began in the United States in 1998, is an example of a successful intervention that significantly reduced the rate of neural tube defects (NTDs). However, despite the drop in NTD rates across all racial/ethnic groups after fortification, Hispanics continue to have the highest rates of this condition. One possible way to reduce this disparity is to fortify corn masa flour to increase the overall intake of folic acid in Hispanic women. We present the available evidence in favor of this approach, address possible safety issues, and outline next steps in the fortification of corn masa flour with folic acid in the United States.
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Mills JL, Carter TC, Scott JM, Troendle JF, Gibney ER, Shane B, Kirke PN, Ueland PM, Brody LC, Molloy AM. Do high blood folate concentrations exacerbate metabolic abnormalities in people with low vitamin B-12 status? Am J Clin Nutr 2011; 94:495-500. [PMID: 21653798 PMCID: PMC3142724 DOI: 10.3945/ajcn.111.014621] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND In elderly individuals with low serum vitamin B-12, those who have high serum folate have been reported to have greater abnormalities in the following biomarkers for vitamin B-12 deficiency: low hemoglobin and elevated total homocysteine (tHcy) and methylmalonic acid (MMA). This suggests that folate exacerbates vitamin B-12-related metabolic abnormalities. OBJECTIVE We determined whether high serum folate in individuals with low serum vitamin B-12 increases the deleterious effects of low vitamin B-12 on biomarkers of vitamin B-12 cellular function. DESIGN In this cross-sectional study, 2507 university students provided data on medical history and exposure to folic acid and vitamin B-12 supplements. Blood was collected to measure serum and red blood cell folate (RCF), hemoglobin, plasma tHcy, and MMA, holotranscobalamin, and ferritin in serum. RESULTS In subjects with low vitamin B-12 concentrations (<148 pmol/L), those who had high folate concentrations (>30 nmol/L; group 1) did not show greater abnormalities in vitamin B-12 cellular function in any area than did those with lower folate concentrations (≤30 nmol/L; group 2). Group 1 had significantly higher holotranscobalamin and RCF, significantly lower tHcy, and nonsignificantly lower (P = 0.057) MMA concentrations than did group 2. The groups did not differ significantly in hemoglobin or ferritin. Compared with group 2, group 1 had significantly higher mean intakes of folic acid and vitamin B-12 from supplements and fortified food. CONCLUSIONS In this young adult population, high folate concentrations did not exacerbate the biochemical abnormalities related to vitamin B-12 deficiency. These results provide reassurance that folic acid in fortified foods and supplements does not interfere with vitamin B-12 metabolism at the cellular level in a healthy population.
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Affiliation(s)
- James L Mills
- Division of Epidemiology, Statistics, and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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Remacha AF, Souto JC, Piñana JL, Sardà MP, Queraltó JM, Martí-Fabregas J, García-Moll X, Férnandez C, Rodriguez A, Cuesta J. Vitamin B12 deficiency, hyperhomocysteinemia and thrombosis: a case and control study. Int J Hematol 2011; 93:458-464. [PMID: 21475950 DOI: 10.1007/s12185-011-0825-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/07/2011] [Accepted: 03/22/2011] [Indexed: 12/31/2022]
Abstract
This study aimed at assessing the relationship between thrombosis, hyperhomocysteinemia and vitamin B12 deficiency using a case-control study carried out in 326 patients with thrombosis (case group) and 351 patients from the same hospital (control group). Apart from the classic risk factors, a number of hematological variables were evaluated, including serum vitamin B12 (B12), red cell folate (RCF), and serum homocysteine (Hcy). An evaluation of serum methylmalonic acid (MMA) and a clinical study were carried out to investigate B12 pathology. Results of univariate analysis demonstrated decreased B12 levels in thrombosis (Student's t test, p < 0.0001). Vitamin B12 below 200 pmol/l (LB200) or below 150 pmol/l (LB150), and red cell folate below 600 nmol/l were found in 17.2, 8.6, and 2.2% of cases with thromboembolism, respectively. An increase in Hcy was detected in 86 cases with thrombosis (26.3%). An abnormality in vitamin B12 and/or renal function was found in 80% of cases with hyperHcy and thrombosis. The MMA increase demonstrated that vitamin B12 deficiency was present in these patients with low levels of vitamin B12 in serum, and the MMA levels were in concordance with Hcy levels. The clinical study revealed B12 malabsorption in most cases with LB200. Multivariate analysis showed that serum vitamin B12 (RR 0.998, CI 0.997-0.999) was moderately related to thromboembolism. The results indicated that vitamin B12 deficiency was common among patients with hyperhomocysteinemia and thrombosis. Moreover, HyperHcy was caused by vitamin B12 deficiency and/or chronic renal failure in most patients with thrombosis. As the main cause of vitamin B12 deficiency was vitamin malabsorption, parenteral vitamin B12 with or without folic acid should be administered for the treatment of this condition. However, it remains to be demonstrated whether this treatment approach prevents recurrent thromboses in patients with vitamin B12 deficiency and thrombosis, as suggested by some case reports.
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Affiliation(s)
- Angel F Remacha
- Department of Hematology, Complejo Hospitalario Toledo, Hospital Virgen de la Salud, Avenida Barber 30, 45004, Toledo, Spain.
| | | | - José Luis Piñana
- Department of Hematology, Hospital de Sant Pau, Barcelona, Spain
| | | | | | | | | | - Cristina Férnandez
- Department of Hematology, Complejo Hospitalario Toledo, Hospital Virgen de la Salud, Avenida Barber 30, 45004, Toledo, Spain
| | - Alvaro Rodriguez
- Department of Hematology, Complejo Hospitalario Toledo, Hospital Virgen de la Salud, Avenida Barber 30, 45004, Toledo, Spain
| | - Jorge Cuesta
- Department of Hematology, Complejo Hospitalario Toledo, Hospital Virgen de la Salud, Avenida Barber 30, 45004, Toledo, Spain
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Crider KS, Bailey LB, Berry RJ. Folic acid food fortification-its history, effect, concerns, and future directions. Nutrients 2011; 3:370-84. [PMID: 22254102 PMCID: PMC3257747 DOI: 10.3390/nu3030370] [Citation(s) in RCA: 359] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 02/21/2011] [Accepted: 03/11/2011] [Indexed: 01/16/2023] Open
Abstract
Periconceptional intake of folic acid is known to reduce a woman’s risk of having an infant affected by a neural tube birth defect (NTD). National programs to mandate fortification of food with folic acid have reduced the prevalence of NTDs worldwide. Uncertainty surrounding possible unintended consequences has led to concerns about higher folic acid intake and food fortification programs. This uncertainty emphasizes the need to continually monitor fortification programs for accurate measures of their effect and the ability to address concerns as they arise. This review highlights the history, effect, concerns, and future directions of folic acid food fortification programs.
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Affiliation(s)
- Krista S. Crider
- The Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA 30033, USA;
- Author to whom correspondence should be addressed; ; Tel.: +1-404-498-3893
| | - Lynn B. Bailey
- The Food Science and Human Nutrition Department, University of Florida, Gainesville, FL 32611, USA;
| | - Robert J. Berry
- The Division of Birth Defects and Developmental Disabilities, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA 30033, USA;
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Obican SG, Finnell RH, Mills JL, Shaw GM, Scialli AR. Folic acid in early pregnancy: a public health success story. FASEB J 2010; 24:4167-74. [PMID: 20631328 DOI: 10.1096/fj.10-165084] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Folate is a water-soluble B vitamin that must be obtained in the diet or through supplementation. For >50 yr, it has been known that folate plays an integral role in embryonic development. In mice, inactivation of genes in the folate pathway results in malformations of the neural tube, heart, and craniofacial structures. It has been shown that diets and blood levels of women who had a fetus with a neural tube defect are low for several micronutrients, particularly folate. Periconceptional use of folic acid containing supplements decreased recurrent neural tube defects in the offspring of women with a previously affected child and the occurrence of a neural tube defect and possibly other birth defects in the offspring of women with no prior history. Based on these findings, the U.S. Public Health Service recommended that all women at risk take folic acid supplements, but many did not. Mandatory food fortification programs were introduced in numerous countries, including the United States, to improve folate nutritional status and have resulted in a major decrease in neural tube defect prevalence. The success story of folate represents the cooperation of embryologists, experimentalists, epidemiologists, public health scientists, and policymakers.
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Affiliation(s)
- Sarah G Obican
- Department of Obstetrics and Gynecology, George Washington University School of Medicine, Washington, District of Columbia, USA
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Circulating unmetabolized folic acid and 5-methyltetrahydrofolate in relation to anemia, macrocytosis, and cognitive test performance in American seniors. Am J Clin Nutr 2010; 91:1733-44. [PMID: 20357042 DOI: 10.3945/ajcn.2009.28671] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Folate deficiency has serious consequences for the fetus. Folic acid fortification of food addresses this problem. However, clinical consequences of vitamin B-12 deficiency may be worsened by high folic acid intakes, perhaps as a direct result of unmetabolized folic acid, which does not occur naturally in body tissues. OBJECTIVE We attempted to attribute associations that we previously found between higher folate status and anemia and cognitive test performance to circulating unmetabolized folic acid or 5-methyltetrahydrofolate (5MeTHF). DESIGN The subjects (n = 1858) were senior participants in the US National Health and Nutrition Examination Survey (1999-2002) who had normal renal function and reported no history of stroke, recent anemia therapy, or diseases of the liver, thyroid, or coronary arteries. Subjects had undergone a phlebotomy, a complete blood count, and cognitive and dietary assessments. RESULTS Circulating unmetabolized folic acid was detected in approximately 33% of the subjects and was related to an increased odds of anemia in alcohol users. In seniors with a serum vitamin B-12 concentration <148 pmol/L or a plasma methylmalonic acid concentration > or =210 nmol/L, the presence compared with the absence of detectable circulating unmetabolized folic acid was related to lower cognitive test scores and lower mean cell volume. In the same subgroup, higher serum 5MeTHF was related to an increased odds of anemia and a marginally significantly decreased odds of macrocytosis. In seniors with a normal vitamin B-12 status, a higher serum 5MeTHF concentration was related to higher cognitive test scores. CONCLUSION Results of this epidemiologic study were somewhat consistent with reports on the folic acid treatment of patients with pernicious anemia, but some findings were unexpected.
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Berry RJ, Bailey L, Mulinare J, Bower C, Dary O. Fortification of Flour with Folic Acid. Food Nutr Bull 2010; 31:S22-35. [DOI: 10.1177/15648265100311s103] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Background After randomized, controlled trials established that consumption of folic acid before pregnancy and during the early weeks of gestation reduces the risk of a neural tube defect (NTD)-affected pregnancy, the United States Public Health Service recommended in 1992 that all women capable of becoming pregnant consume 400 μg folic acid daily. In 1998, folic acid fortification of all enriched cereal grain product flour was fully implemented in the United States and Canada. Objective To provide guidance on national fortification of wheat and maize flours to prevent 50 to 70% of the estimated 300,000 NTD-affected pregnancies worldwide. Methods An expert workgroup reviewed the latest evidence of effectiveness of folic acid flour fortification and the safety of folic acid. Results Recent estimates show that in the United States and Canada, the additional intake of about 100 to 150 μg/day of folic acid through food fortification has been effective in reducing the prevalence of NTDs at birth and increasing blood folate concentrations in both countries. Most potential adverse effects associated with folic acid are associated with extra supplement use not mandatory fortification. Fortification of wheat flour has a proven record of prevention in other developed countries. In 2009, 51 countries had regulations written for mandatory wheat flour fortification programs that included folic acid. Conclusions NTDs remain an important cause of perinatal mortality and infantile paralysis worldwide. Mandatory fortification of flour with folic acid has proved to be one of the most successful public health interventions in reducing the prevalence of NTD-affected pregnancies. Most developing countries have few, if any, common sources of folic acid, unlike many developed countries, which have folic acid available from ready-to-eat cereals and supplements. Expanding the number of developed and developing countries with folic acid flour fortification has tremendous potential to safely eliminate most folic acid-preventable NTDs.
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Wehby GL, Castilla EE, Lopez-Camelo JS, Murray JC. Predictors of multivitamin use during pregnancy in Brazil. Int J Public Health 2009; 54:78-87. [PMID: 19296054 DOI: 10.1007/s00038-009-8103-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVES The study aimed at identifying predictors of multivitamin use during pregnancy in Brazil. METHODS Birth registry data of 1,774 infants at maternity hospitals in Brazil were used. The effects of maternal health and fertility risk indicators, enabling factors and other maternal characteristics on multivitamin use were evaluated both pooled and stratified by African ancestry. RESULTS About 14% of the women used multivitamins during pregnancy. Number of previous live births, maternal age and education, number of ultrasound exams and year of pregnancy had significant effects on multivitamin use in the group reporting African ancestry. Maternal acute illnesses and education had significant effects on use in the group without African ancestry. Significant geographic variation in multivitamin use was observed in both groups. CONCLUSIONS The study identifies several risk indicators, health care access and enabling factors that are predictive of multivitamin use with differences by African ancestry. The study highlights the importance of increasing the awareness of women of childbearing age of the benefits of multivitamin use and identifies barriers that need to be addressed to promote use.
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Affiliation(s)
- George L Wehby
- College of Public Health, Department of Health Management and Policy, University of Iowa, E204, GH, Iowa City, IA 52242, USA.
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Piyathilake CJ, Macaluso M, Alvarez RD, Bell WC, Heimburger DC, Partridge EE. Lower risk of cervical intraepithelial neoplasia in women with high plasma folate and sufficient vitamin B12 in the post-folic acid fortification era. Cancer Prev Res (Phila) 2009; 2:658-64. [PMID: 19542191 DOI: 10.1158/1940-6207.capr-08-0175] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The purpose of this study was to determine the influence of plasma folate and vitamin B12 concentrations on cervical cancer risk in the U.S. after the folic acid fortification era. The study included 376 premenopausal women of childbearing age who tested positive for infections with high-risk (HR) human papillomaviruses (HPVs) and were diagnosed with cervical intraepithelial neoplasia (CIN) grade 2 or higher (CIN 2+, cases) or <or=CIN 1 (noncases). CIN 2+ (yes/no) was the dependent variable in logistic regression models that specified plasma folate concentrations combined with plasma B12 concentrations as the independent predictors of primary interest, adjusting for age, race, education, smoking, parity, number of life-time male sexual partners, use of contraceptives, waist circumference, physical activity, healthy eating index, and circulating concentrations of vitamins A, C, tocopherol, and total carotene. Women with supraphysiologic concentrations of plasma folate (>19.8 ng/mL) who also had sufficient plasma vitamin B12 (>or=200.6 pg/mL) had 70% lower odds of being diagnosed with CIN 2+ (P = 0.04) when compared with women with plasma folate of <or=19.8 ng/mL and plasma vitamin B12 of <200.6 pg/mL. Our results do not corroborate the concern that supraphysiologic plasma folate concentrations seen in the post-U.S. folic acid fortification era increase the risk of CIN in premenopausal women of childbearing age. In fact, higher folate is associated with significantly lower risk of CIN, especially when vitamin B12 is sufficient, demonstrating the importance of vitamin B12 in the high-folate environment created by the folic acid fortification program.
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Affiliation(s)
- Chandrika J Piyathilake
- Department of Nutrition Sciences, University of Alabama at Birmingham, 1675 University Boulevard, Webb 326, Birmingham, AL 35294, USA.
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Periconceptional Folic Acid Supplementation: A New Indication for Therapeutic Drug Monitoring. Ther Drug Monit 2009; 31:319-26. [DOI: 10.1097/ftd.0b013e31819f3340] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bentley TG, Weinstein MC, Willett WC, Kuntz KM. A cost-effectiveness analysis of folic acid fortification policy in the United States. Public Health Nutr 2009; 12:455-67. [PMID: 18590584 PMCID: PMC3856722 DOI: 10.1017/s1368980008002565] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To quantify the health and economic outcomes associated with changes in folic acid consumption following the fortification of enriched grain products in the USA. DESIGN Cost-effectiveness analysis. SETTING Annual burden of disease, quality-adjusted life years (QALY) and costs were projected for four steady-state strategies: no fortification, or fortifying with 140, 350 or 700 microg folic acid per 100 g enriched grain. The analysis considered four health outcomes: neural tube defects (NTD), myocardial infarctions (MI), colon cancers and B12 deficiency maskings. SUBJECTS The US adult population subgroups defined by age, gender and race/ethnicity, with folate intake distributions from the National Health and Nutrition Examination Surveys (1988-1992 and 1999-2000), and reference sources for disease incidence, utility and economic estimates. RESULTS The greatest benefits from fortification were predicted in MI prevention, with 16 862 and 88 172 cases averted per year in steady state for the 140 and 700 microg fortification levels, respectively. These projections were between 6261 and 38 805 for colon cancer and 182 and 1423 for NTD, while 15-820 additional B12 cases were predicted. Compared with no fortification, all post-fortification strategies provided QALY gains and cost savings for all subgroups, with predicted population benefits of 266 649 QALY gained and $3.6 billion saved in the long run by changing the fortification level from 140 microg/100 g enriched grain to 700 microg/100 g. CONCLUSIONS The present study indicates that the health and economic gains of folic acid fortification far outweigh the losses for the US population, and that increasing the level of fortification deserves further consideration to maximise net gains.
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Affiliation(s)
- Tanya Gk Bentley
- The Faculty of Arts and Sciences, Harvard University PhD Program in Health Policy, Cambridge, MA, USA
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Ganji V, Kafai MR. Hemoglobin and hematocrit values are higher and prevalence of anemia is lower in the post-folic acid fortification period than in the pre-folic acid fortification period in US adults. Am J Clin Nutr 2009; 89:363-71. [PMID: 19056553 DOI: 10.3945/ajcn.2008.26287] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND It is not known whether the improved folate status from mandatory folic acid fortification had any impact on indexes and prevalence of anemias in the United States. OBJECTIVE We investigated trends in indexes and prevalence of anemia and macrocytosis with a focus on comparison of prefortification data with postfortification data. DESIGN Hemoglobin, hematocrit, mean corpuscular volume (MCV) and prevalences and likelihood of anemia and macrocytosis were determined for 26,596 adults examined in the National Health and Nutrition Examination Surveys, 1988-2004. RESULTS From 1988-1994 to 1999-2004, hemoglobin modestly but significantly improved from 15.1 to 15.4 g/dL (approximately 2.0%; P < 0.0001) and from 13.3 to 13.6 g/dL (approximately 2.3%; P < 0.0001) in men and women, respectively. There was a significant increase in MCV from 1988-1994 to 1999-2004 in men (from 90.2 to 90.7; P = 0.0123) and older (>60 y) men (from 91.6 to 92.4; P = 0.0105) and in women (from 90.7 to 91.4; P = 0.0141). Only in women was the prevalence of anemia significantly lower in 1999-2004 than in 1988-1994 (27.9% reduction; P = 0.0005). The odds of having anemia in the postfortification period relative to the prefortification period was 0.64 (95% CI: 0.54, 0.75; P < 0.0001) in women and 0.79 (95% CI: 0.62, 0.99; P < 0.0433) in men. In general, the prevalence of macrocytosis and the odds of having macrocytosis did not change significantly from 1988-1994 to 1999-2004. CONCLUSION The improvement in hemoglobin and the decreased prevalence of anemia from 1988-1994 to 1999-2004, especially in women, may be attributable to improved folate status, increased vitamin/mineral supplements use, and other unknown causes after the initiation of folic acid fortification. The cause of increased MCV in men, and in older persons of both sexes, warrants further investigation.
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Affiliation(s)
- Vijay Ganji
- Division of Nutrition, School of Health Professions, College of Health and Human Sciences, Georgia State University, Atlanta, GA 30302, USA.
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Mills JL, Carter TC. Invited commentary: Preventing neural tube defects and more via food fortification? Am J Epidemiol 2009; 169:18-21; discussion 22-3. [PMID: 18953060 DOI: 10.1093/aje/kwn329] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many neural tube defects can be prevented if women take folic acid around the time of conception. However, the majority of women do not take folic acid at the critical time, so the US government required that food be fortified with folic acid effective January 1, 1998. Whether the amount being added was sufficient to prevent all folate-related neural tube defects has been hotly debated. Mosley et al. (Am J Epidemiol. 2008;169(1):9-17) found no evidence that folic acid supplement use or dietary folate intake was related to neural tube defects, indicating that fortified food is probably providing sufficient folic acid to prevent folate-related defects. Because data on the effectiveness of fortification in the United States are scarce, this is an important contribution. There is great interest in the other effects of fortification. Folic acid reduces homocysteine levels, and homocysteine has been linked to cardiovascular disease and cancer. On the basis of current evidence, however, it seems unlikely that fortification will reduce cardiovascular disease rates. Its effect on cancer remains unclear. Folic acid may be useful in primary prevention but may also stimulate the growth of existing malignancies or premalignant lesions. Although these issues remain unresolved, Mosley et al. have provided important data to address the primary question: Does fortification prevent folate-related neural tube defects?
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Affiliation(s)
- James L Mills
- Division of Epidemiology, Statistics, and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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Bognár M, Ponyi A, Hauser P, Müller J, Constantin T, Jakab Z, Schuler D, Garami M. Improper supplementation habits of folic acid intake by Hungarian pregnant women: improper recommendations. J Am Coll Nutr 2008; 27:499-504. [PMID: 18978170 DOI: 10.1080/07315724.2008.10719731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Neural tube defects (NTDs) are some of the most common congenital anomalies. Proper folic acid supplementation is a dominant risk factor, which has been shown to decrease the incidence of NTDs. In Canada, the incidence of neuroblastoma has presented a considerable decrease of 60% as a result of enrichment cereal grain flours with synthetic folic acid. The aim of this study was to investigate the effect of folic acid intake by pregnant women on the incidence of NTDs and neuroblastoma. METHODS Regular folic acid intake has been recommended to pregnant women in Hungary since the eighties of the last century by health visitors eventually raking effect as an official protocol which had been released in 1997. During 2001, 2002 and 2003, folic acid intake habits of pregnant women were evaluated by health visitors, proving to be successful in collecting data from 95.06% of the pregnant women. The incidence of NTDs has been registered by the Hungarian National Centre of Epidemiology, Department of Human Genetics and Teratology. The Pediatric Cancer Registry provided the incidence of neuroblastoma in children. RESULTS Consistent findings revealed a regular intake of supplementary folic acid products by 68.71% of the pregnant women. Out of these, 93.13% of pregnant women who were taking folic acid, started the supplementation after their 7 weeks of pregnancies, a time designated as the completion period of the development of the neural tube. The dose of folic acid supplementation was evaluated as less than 5 mg/day in 84.75% of the pregnant women. In Hungary, the incidence of NTDs has remained constant, while the incidence of neuroblastoma has shown constant slight increase in spite of the introduction of folic acid supplementation in 1997. CONCLUSIONS Based on our experience, folic acid supplementation was initiated after the recognition of pregnancy and its application in a dose of lower than 5 mg/day neither decreased the incidence of NTDs nor did it have an effect on the neuroblastoma incidence. It is implicated that proper folic acid supplementation, which is started from the conception, can be achieved only with the enrichment of cereal grain flours.
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Affiliation(s)
- Márta Bognár
- Semmelweis University, Faculty of Medicine, 2nd Department of Pediatrics, Budapest, Hungary
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Abstract
The Chilean Ministry of Health legislated to add folic acid (2.2 mg/100 g) to wheat flour to reduce the risk of neural tube defects (NTD), beginning in January 2000. This policy resulted in a significant increase in serum and red blood cell folate in women of childbearing age 1 year after fortification. The frequency of NTD was studied in all births, both live and stillbirths, in a prospective hospital-based design including 25% of national births during 1999–2000 (prefortification period) and 2001–2002 (postfortification period). During the prefortification period, there was a total of 120,566 newborns, and the NTD rate was 17.1/10,000 births. During the postfortification period (2001–2002) there was a total of 117,704 newborns, and the NTD rate was significantly reduced by 43% to 9.7/10,000 births (RR = 0.57; 95% CI, 0.45 to 0.71). This implies a reduction of 43% in the rate of NTD. The costs per NTD case and infant death averted were 1,200 international dollars (I$) and I$11,000, respectively. The cost per disability-adjusted life year (DALY) averted was I$91, or 0.8% of the country's per capita GDP. On the overall, fortification resulted in net cost savings of I$1.8 million. Fortification of wheat flour with folic acid has proven to be an effective and cost saving strategy for the primary prevention of NTD in a middle-income country in a postepidemiological transition, and in a dramatically short period of time.
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Intake and status of folate and related B-vitamins: considerations and challenges in achieving optimal status. Br J Nutr 2008; 99 Suppl 3:S48-54. [DOI: 10.1017/s0007114508006855] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Folate and the metabolically related B-vitamins, vitamin B12and riboflavin, have attracted much scientific and public health interest in recent years. Apart from a well established role in preventing neural tube defects (NTDs), evidence is emerging to support other potential roles for folate and/or related B-vitamins in protecting against cardiovascular disease (especially stroke), certain cancers, cognitive impairment and osteoporosis. However, typical folate intakes are sub-optimal, in that although adequate in preventing clinical folate deficiency (i.e. megaloblastic anaemia) in most people, they are generally insufficient to achieve a folate status associated with the lowest risk of NTDs. Natural food folates have a limited ability to enhance folate status as a result of their poor stability under typical cooking conditions and incomplete bioavailability when compared with the synthetic vitamin, folic acid (as found in supplements and fortified foods). Current folate recommendations to prevent NTDs (based primarily on folic acid supplementation) have been found to be ineffective in several European countries. In contrast, in North America and Chile, the policy of mandatory folic acid-fortification has proven itself in terms of lowering the prevalence of NTD, but remains controversial because of concerns regarding potential risks of chronic exposure to high-dose folic acid. In the case of vitamin B12, the achievement of an optimal status is particularly difficult for many older people because of the common problem of food-bound B12malabsorption. Finally, there is evidence that riboflavin status is generally low in the UK population, and particularly so in younger women; this warrants further investigation.
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