What is folic acid?

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From the Guidelines

Folic Acid Definition and Importance

Folic acid, also known as vitamin B9, is a crucial nutrient that plays a significant role in various bodily functions, including cell growth and development. It is particularly important for pregnant women, as it helps prevent birth defects of the brain and spine, such as neural tube defects 1.

Recommended Dosage and Timing

The recommended dosage of folic acid for pregnant women is 400-800 micrograms per day, starting at least one month before conception and continuing through the first trimester 1. Women with certain health risks, such as epilepsy, insulin-dependent diabetes mellitus, or obesity, may require a higher dosage of 4-5 mg of folic acid daily 1.

Benefits and Risks

The benefits of folic acid supplementation include a reduced risk of neural tube defects by nearly 75% 1. The risks associated with folic acid supplementation are minimal, with no serious harms reported at usual doses 1.

Clinical Considerations

Clinicians should advise all women who are capable of pregnancy to take folic acid supplements, as most pregnancies in the United States are unplanned 1. The effective amount of additional folic acid supplementation in settings where food is fortified with folic acid is unclear 1.

Key Points

  • Folic acid is essential for preventing birth defects of the brain and spine
  • Recommended dosage: 400-800 micrograms per day for pregnant women
  • Higher dosage (4-5 mg) may be required for women with certain health risks
  • Folic acid supplementation reduces the risk of neural tube defects by nearly 75%
  • Minimal risks associated with folic acid supplementation at usual doses

From the FDA Drug Label

Folic acid, N-[ρ-[[(2-amino-4-hydroxy-6-pteridinyl) methyl]-amino]benzoyl]-L-glutamic acid, is a B complex vitamin containing a pteridine moiety linked by a methylene bridge to para-aminobenzoic acid, which is joined by a peptide linkage to glutamic acid. Folic acid is a B complex vitamin that is necessary for nucleoprotein synthesis and erythropoiesis. It is a precursor to tetrahydrofolic acid, which is involved in the biosynthesis of purines and thymidylates of nucleic acids.

  • Folic acid is also known as a pteridine moiety linked to para-aminobenzoic acid and glutamic acid.
  • It is found in foods such as liver, kidneys, yeast, and leafy green vegetables. 2 2

From the Research

Definition of Folic Acid

  • Folic acid is the synthetic form of vitamin B9, found in supplements and fortified foods, while folate occurs naturally in foods 3, 4, 5, 6.
  • It is crucial for homeostatic function of the biological system and is not endogenously produced 4, 5, 6.

Importance of Folic Acid

  • Folic acid is extremely important in the synthesis of nucleic acids (DNA and RNA) and different proteins 3.
  • It acts as a coenzyme for the transfer of 1 carbon in the biosynthesis of purine, pyrimidine, and amino acids 3.
  • Folic acid is critically important in rapidly proliferating tissues, including fetus and trophoblastic tissue to prevent neural tube defect (NTD) 3.
  • It plays a very important role in the prevention of neural tube defects and megaloblastic anemia, the proper functioning of the nervous system, as well as reducing the risk of developing certain cancers 5, 6.

Health Benefits of Folic Acid

  • Folic acid supplementation is recommended for pregnant women to prevent neural tube defects, maternal anaemia, puerperal sepsis, low birthweight, and preterm birth 3, 7.
  • It is also important for the prevention of megaloblastic anemia, various cardiovascular diseases, obstetrical complications, neuropsychiatric diseases, and tumors 6.
  • Folic acid has a preventive effect in many diseases, including neural tube defects, megaloblastic anemia, and certain cancers 5, 6.

Folic Acid Deficiency

  • Decreased blood folic acid levels can inhibit DNA replication, repair, RNA synthesis, histone and DNA methylation, methionine production, and homocysteine remethylation reactions, leading to neural tube defects and other health problems 3.
  • Folate deficiency can lead to genetic, epigenetic, and metabolic changes, and is related to the development of megaloblastic anemia, cardiovascular diseases, and neuropsychiatric diseases 6.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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