ReviewEuropean journal of clinical nutrition2016
What is the safe upper intake level of folic acid for the nervous system? Implications for folic acid fortification policies.
Review in European journal of clinical nutrition, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
23 citing papers in PubMed, 41 citations in OpenAlex.
- Reassessing Mandatory Folic Acid Fortification for Neural Tube Defect Prevention: Evidence, Uncertainty, and Policy Implications.Nutrients · 2026Review
- Taurine and Betaine, Alone and in Combination, Mitigate Lysis of Canine Erythrocytes in an In Vitro Model of Iron-Deficiency Anemia.Veterinary and animal science · 2026Article
- Longitudinal Trends and Analytical Consistency of Folate and Vitamin BBiomedicines · 2026Article
- Fortification, folate and vitamin B12 balance, and the nervous system. Is folic acid excess potentially harmful?European journal of clinical nutrition · 2025Review
- Biological, dietetic and pharmacological properties of vitamin BNPJ science of food · 2025Review
- Article
- Article
- Association between dietary folate intake and the risk of osteoporosis in adults: a cross-sectional study.BMC musculoskeletal disorders · 2024Article
- Vitamin B12 status and folic acid supplementation influence mitochondrial heteroplasmy levels in mice.PNAS nexus · 2024Article
- Association between dietary folate intake and severe headache or migraine in adults: a cross-sectional study of the National Health and Nutrition Examination Survey.Frontiers in nutrition · 2024Article
- Uncovering the Hidden Dangers and Molecular Mechanisms of Excess Folate: A Narrative Review.Nutrients · 2023Review
- Integrated surveillance strategy to support the prevention of neural tube defects through food fortification with folic acid: the experience of Costa Rica.Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery · 2023Review
- Molecular pathways and nutrigenomic review of insulin resistance development in gestational diabetes mellitus.Frontiers in nutrition · 2023Review
- Review
- Food matrix structure (from Biscuit to Custard) has an impact on folate bioavailability in healthy volunteers.European journal of nutrition · 2021Article
- High folic acid or folate combined with low vitamin B-12 status: potential but inconsistent association with cognitive function in a nationally representative cross-sectional sample of US older adults participating in the NHANES.The American journal of clinical nutrition · 2020Article
- Folic Acid Fortification and Neural Tube Defect Risk: Analysis of the Food Fortification Initiative Dataset.Nutrients · 2020Article
- Nutritional and medical food therapies for diabetic retinopathy.Eye and vision (London, England) · 2020Review
- Biomarkers of Nutrition for Development (BOND): Vitamin B-12 Review.The Journal of nutrition · 2018Review
- Testicular MTHFR deficiency may explain sperm DNA hypomethylation associated with high dose folic acid supplementation.Human molecular genetics · 2018Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
1 author at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Between 1945 and 1959 it was convincingly documented that folic acid can precipitate or aggravate the neurological and haematological consequences of vitamin B12 deficiency by increasing the demand for vitamin B12. Since then there has been much misunderstanding of the issues, mainly by advocates of folic acid fortification who have been inclined to minimise or even dismiss the risks by misinterpreting the evidence as only a 'masking' of the anaemia of pernicious anaemia. Recent studies in the era of fortification are rediscovering the risks to the nervous system, especially cognitive function, of excess folate in the presence of vitamin B12 deficiency. I have reviewed the Reports of four Expert Advisory Committees in Europe and the USA, which suggest that the safe upper tolerable limit (UL) for folic acid is 1 mg in adults. These reports are unsound and there is already evidence of neurological harm from long-term exposure to doses of folic acid between 0.5 and 1 mg in the presence of vitamin B12 deficiency. There is an urgent need to review the safe UL for folic acid and to consider the addition of vitamin B12 to folic acid fortification policies.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.