DNA and RNA, and amino acids, and formation of red blood cells. It is famous as the “pregnancy vitamin” because of its widely use in pregnancy and its ability to prevent the baby from developing birth defects in the nervous system.
Para – aminobenzoic acid (PABA; vitamin B10) is a part of the structure of folic acid. This is why folic acid is sometimes referred to as “vitamin within a vitamin”. It is chemically pteroylglutamic acid.
Functions of Folic Acid:
- It is required for the synthesis of DNA and RNA.
- It is necessary for the formation of red blood cells.
- It acts as a coenzyme for the synthesis of methionine, which is the precursor for SAMe (S – adenosylmethionine).
- As the coenzyme THFA (tetrahydrofolic acid), it helps with the metabolism of proteins.
- It plays an important role in the development of the central nervous system.
- It helps reduce blood levels of homocysteine.
- It is important in the production and quality of sperms and the maturation of ovum.
Food Sources and Absorption:
Most foods contain some folic acid. The highest concentrations are 
found in green leafy vegetables (such as spinach, kale, beet greens, and chard), brewer`s yeast, nuts, and the liver. They contain more than 100 mcg of folic acid per 100 grams. Other food sources are legumes, asparagus, broccoli, sweet potatoes, okra, artichoke, parsnips, citrus fruits, pineapple, bananas, cantaloupe, and berries. It also is produced in the body by intestinal bacteria. Folic acid is easily destroyed by heating, especially in large volume of water.
Approximately 50% of dietary folic acid is absorbed from the upper part of the small intestine. Total amount of folic acid in an average person is about 10 mg, with the liver containing the largest store. About 200 mcg of folic acid a day is needed to maintain its store in the body. The body store is enough for only 4 – 6 months.
Dietary folic acid needs vitamins C and B3 to convert to its active form THFA (tetrahydrofolic acid) before entering into the blood stream. Also about 60 – 90 mcg of folic acid is excreted into the small intestine via bile every day, which may contribute to folic acid deficiency.
Athletic Benefits of Folic Acid:
- Along with vitamins B6 and B12, folic acid is highly important for the conversion of creatine into phosphocreatine (CP), maximizing the benefits of creatine monohydrate.
- In conjunction with vitamins C and B12, folic acid helps with the metabolism of proteins.
- May delay fatigue and exercise– induced exhaustion.
Non – Athletic Benefits of Vitamin Folic Acid:
The following conditions may benefit from folic acid:
- Prevention of birth defects, such as spina bifida, meningocele,
encephalocele, anencephaly, cleft palate, and harelip. - Abnormal Pap smear.
- Depression.
- Schizophrenia.
- Anemia.
- Periodontal disease.
- Cervical cancer.
- Cervical dysplasia.
- Dementia.
- Gout.
- Breast cancer.
- Colon cancer (prevention).
- Atherosclerosis.
- High homocysteine levels.
- Chronic fatigue syndrome.
- Skin problems, such as psoriasis, acne, seborrheic dermatitis, vitiligo, and ulcers.
- Inflammatory bowel disease (IBD).
- Infertility (both in men and women).
- Restless leg syndrome.
- Lung cancer (prevention).
- Down`s syndrome.
- Preeclampsia.
- Sickle cell anemia.
- Epilepsy.
- Celiac disease.
- Chronic hemolytic anemias.
Deficiency of Folic Acid:
When dietary intake of folic acid is less than 100 mcg per day, the folic acid store would be sufficient for only 4 – 6 months followed by developing symptoms of folic acid deficiency. They include anemia, fatigue, irritability, loss of appetite, inflammation of the tongue, depression, impaired judgment, and paranoia.
The contributing factors to deficiency of folic acid are:
- Alcoholism.
- Old age.
- Poor diet.
- Malabsorption.
- Celiac disease.
- Crohn`s disease.
- Pregnancy.
- Breastfeeding.
- Psoriasis.
- Diabetic neuropathy of the GI tract.
- Dialysis.
- Birth control pills.
- High doses of vitamin C (more than 2000 mg per day).
- Congestive heart failure.
- Medications: sulfasalazine, pyrimethamine, triamterene, cholestyramine, phenformin, metformin, barbiturates, phenytoin, primidone, tetracycline, methotrexate, and nitrofurantoin.
- Leukemia.
- Lymphoma.
- Liver disease.
Dosage and Side Effects:
The RDA for folic acid in adults is 400 mcg. It is increased during pregnancy and breastfeeding to 600 mg and 500 mg per day, respectively. The performance daily intake (PDI) for athletes and physically active adults is 800 – 1200 mcg.
Although folic acid is added to all multivitamin products, it is also available in tablets as 400 mcg, 800 mcg, and 1000 mcg.
Up to 2000 mcg of folic acid per day usually has no side effects. However, very higher doses may cause insomnia, irritability, stomach upset, diarrhea, and skin eruptions.
Interactions:
- Anti – seizure medications (phenobarbital, phenytoin, and primidone): folic acid may decrease their effectiveness.
- Methotrexate: folic acid may decrease the effectiveness of this medication.
- Pyrimethamine: folic acid may decrease the effectiveness of this medication.
