Folic Acid


Folic acid is a member of the water-soluble B vitamin group. Isolated in 1946 from spinach leaves, its name comes from folium, the Latin word for leaf. In the body, folic acid is converted to a more biologically active form.

Folic acid occurs in a wide variety of foods. Best sources include dark green leafy vegetables, brewer’s yeast, liver, and eggs. Other good sources are beets, broccoli, brussels sprouts, orange juice, cabbage, cauliflower, cantaloupe, kidney and lima beans, wheat germ, and whole grain cereals and breads. The body’s “friendly” intestinal bacteria also produce folic acid.

Dosage Info

Dosage Range

200-800mcg daily. However, physicians may occasionally administer doses to severely deficient patients ranging from 5,000-15,000mcg daily. (1)

Most Common Dosage

400mcg daily.

Dosage Forms

Tablets, capsules, liquids, liposomal sprays, and effervescent tablets.

Interactions and Depletions



Reported Uses

Like vitamin B12, folic acid is necessary for the production of both DNA and RNA. It is therefore essential for proper cellular division and the transmission of the genetic code to all newly formed cells. It is also essential for the health of red blood cells (2) and the production of proteins and various amino acids.

In women, folic acid is crucial for closure of the fetus’ neural tube during pregnancy. This makes adequate folic acid levels essential for preventing neural tube birth defects such as spina bifida. (3) , (4) , (5) In general, pregnancy increases a woman’s requirements for folic acid. (6) , (7) Women with higher intakes of folic acid may have a reduced risk of ovarian cancer. (8) Also, of importance to women, folic acid may treat cervical dysplasia and decrease the necessity of hysterectomies. (9)

Studies also suggest that many people with major depression or schizophrenia may benefit from folic acid supplementation. (10) Benefit may also be extended to alcoholics, who are commonly deficient in folic acid. (11) One form of anemia that arises from folic acid deficiency can also be reversed with supplementation. (12)


Studies have shown cognitive skills such as knowing, thinking, learning, and judging can be impaired in older adults with low levels of certain B vitamins. Supplementation with folate, vitamin B12, and vitamin B6 has been effective in enhancing cognitive performance in older adults. (13) In fact, studies in older adults noted that subjects with low levels of vitamin B12 or folate had more of a risk of developing Alzheimer's disease. (14) , (15)

Folic acid can also lower homocysteine levels, even when the levels are increased by lipid lowering medications. (16) , (17) , (18) , (19) , (20) Because homocysteine is an amino acid that is a significant risk factor for atheroslerosis, folic acid may prevent the development and progression of the disease. (21) The same effect has been noted when folic acid is given in conjunction with vitamin B6. (22) Hemodialysis patients were treated with B-vitamins and folic acid which significantly lowered homocysteine levels. (23) Dietary supplementation with the B-vitamins prevented hyperhomocysteinemia but did not prevent the development of vascular dysfunction or atherosclerotic lesions. (24) Other studies involving hundreds of patients who had undergone successful coronary angioplasty have evaluated these individuals following six months of therapy on vitamin B6, vitamin B12, and folic acid, comparing the results to patients on placebo. After one year, the patients on the vitamin therapy had lower rates of related cardiovascular events including heart attacks and repeated angioplasty. (25) , (26) Homocysteine can also interfere with normal bone structure, folic acid’s homocysteine-lowering function may also be of benefit in the prevention of osteoporosis. (27) , (28) , (29)

Finally, folic acid in mouthwash form may offer treatment for inflammation of the gums, or gingivitis. (30)

Toxicities & Precautions


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This dietary supplement is considered safe when used in accordance with proper dosing guidelines.

Large doses of this dietary supplement may mask vitamin B12 deficiency. (31)

Pregnancy / Breast Feeding

To date, the medical literature has not reported any adverse effects related to fetal development during pregnancy or to infants who are breast-fed. Proper nutrition is essential during pregnancy for the healthy development of the fetus. Numerous vitamins and minerals are a vital part of proper nutrition. If you are pregnant, think you might be pregnant, trying to get pregnant, or breast-feeding an infant, talk to your healthcare professional about supplementing your diet with appropriate vitamins and minerals.

Age Limitations

To date, the medical literature has not reported any adverse effects specifically related to the use of this dietary supplement in children. Vitamins and minerals are an essential part of proper growth and development. Talk to your healthcare professional about the appropriate use of vitamins and minerals in children. Do not use any vitamin or mineral in children under 2 years of age unless first discussed with your healthcare professional.


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