SynthesisNutrients2022
Women Taking a Folic Acid Supplement in Countries with Mandatory Food Fortification Programs May Be Exceeding the Upper Tolerable Limit of Folic Acid: A Systematic Review.
Synthesis in Nutrients, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 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.
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Who cites it
24 citing papers in PubMed, 40 citations in OpenAlex.
- Serum Concentrations of Folate Forms Following Supplementation of Multimicronutrients with 400 µg or 800 µg Mix of (6S)-5-Methyltetrahydrofolate and Folic Acid (1:1) in Women of Childbearing Age.Molecular nutrition & food research · 2024Trial
- Optimal folic acid dosage in lowering homocysteine: Precision Folic Acid Trial to lower homocysteine (PFAT-Hcy).European journal of nutrition · 2024Trial
- Folic acid prevention of neural tube defects requires retinoic acid produced by ALDH1L1.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- High folic acid supplementation is associated with vaginal bleeding in early pregnancy in a fetal sex-specific manner: findings from two prospective cohort studies.Reproductive health · 2026Article
- Congenital heart disease and folate pathway gene polymorphisms: findings from a North Indian cohort.BMC cardiovascular disorders · 2026Article
- Excess folic acid disrupts placental endocrine functionFrontiers in nutrition · 2026Article
- Fortification, folate and vitamin B12 balance, and the nervous system. Is folic acid excess potentially harmful?European journal of clinical nutrition · 2025Review
- Article
- Health professionals require more defined protocols, better funding and patient resources to support couples with recurrent pregnancy loss.Scientific reports · 2025Article
- Maternal dietary folate imbalance alters cerebellar astrocyte morphology and density in offspring.IBRO neuroscience reports · 2025Article
- Biological, dietetic and pharmacological properties of vitamin BNPJ science of food · 2025Review
- Review
- Pharmacokinetics of (6S)-5-Methyltetrahydrofolate dicholine salt compared to folic acid: a randomized double-blind single dose cross-over study.Food & nutrition research · 2025Article
- Association between MTHFR polymorphisms and vitamin D status in infertile women: a mediation analysis.Frontiers in nutrition · 2025Article
- The association of metabolic profile of folate with diabetic kidney disease: evidence from 2011-2020 cycles of the NHANES.Renal failure · 2024Article
- Maternal Serum Folate During Pregnancy and Congenital Heart Disease in Offspring.JAMA network open · 2024Article
- Folic Acid and Selected Risk Factors for Fetal Heart Defects-Preliminary Study Results.Nutrients · 2024Article
- Dietary supplements, guideline alignment and biochemical nutrient status in pregnancy: Findings from the Queensland Family Cohort pilot study.Maternal & child nutrition · 2024Observational
- Uncovering the Hidden Dangers and Molecular Mechanisms of Excess Folate: A Narrative Review.Nutrients · 2023Review
- Does maternal genetic liability to folate deficiency influence the risk of antiseizure medication-associated language impairment and autistic traits in children of women with epilepsy?The American journal of clinical nutrition · 2023Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundIn preconception and pregnancy, women are encouraged to take folic acid-based supplements over and above food intake. The upper tolerable limit of folic acid is 1000 mcg per day; however, this level was determined to avoid masking a vitamin B12 deficiency and not based on folic acid bioavailability and metabolism. This review's aim is to assess the total all-source intake of folate in women of childbearing age and in pregnancy in high-income countries with folate food fortification programs.
methodsA systematic search was conducted in five databases to find studies published since 1998 that reported folate and folic acid intake in countries with a mandatory fortification policy.
resultsWomen of childbearing age do not receive sufficient folate intake from food sources alone even when consuming fortified food products; however, almost all women taking a folic acid-based supplement exceed the upper tolerable limit of folic acid intake.
conclusionsFolic acid supplement recommendations and the upper tolerable limit of 1000 mcg set by policy makers warrant careful review in light of potential adverse effects of exceeding the upper tolerable limit on folic acid absorption and metabolism, and subsequent impacts on women's health during their childbearing years.
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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.