Folic acid, sometimes called B9, is another of the water-soluble B complex vitamins. It is extremely important in cellular metabolism including the synthesis of components of DNA and RNA. Adequate intake can reduce damage to DNA. It is also necessary for normal red blood cell formation and deficiency can lead to one form of anemia that is difficult to distinguish from vitamin B12 deficiency.
Folic acid deficiency is common in diseases of the small intestine that interfere with the absorption of folic acid from food and the recycling of folic acid from the liver back to the intestines. Excessive intake of alcohol can result in folic acid deficiency. It is important to note that folic acid function can be hampered by several drugs including large doses of nonsteroidal anti-inflammatory drugs, methotrexate, trimethoprim, cholestyramine, isoniazid, and triamterene.
We have known for decades that adequate folic acid intake is associated with a reduced risk of neural tube birth defects and is essential during pregnancy. Overwhelming evidence shows that women given folic acid supplements during pregnancy have a lower incidence of delivering babies with neural tube birth defects such as spina bifida. Oral contraceptives cause lower folate levels in women and may result in deficiency if they become pregnant soon after stopping the pill.
In spite of public awareness growing about folic acid, as many as 68-87% of American women of childbearing age still have folic acid intakes below the recommended 400 micrograms per day. They elderly are also at increased risk for folate deficiencies – which may exacerbate the risk associated with heart disease, cancer and neurological impairments which are more prevalent in this population. Several recent studies have suggested that folate supplementation should be considered in elderly people, especially those with elevated plasma total homocysteine levels and cardiovascular disease, as well as in those individuals who experience neuropsychiatric disorders. Topical folic acid formulations are used for gingival hyperplasia that result from phenytoin (Dilantin) therapy and for gingivitis associated with pregnancy.
Dietary Sources: Fruits and veggies: dark leafy greens, oranges and orange juice, beans and peas, and brewer’s yeast is also a good source of folic acid and other B vitamins.
Dosage: The RDA for folic acid for adults over 13 years, 400 micrograms; for pregnant women, 600 micrograms; and lactating women, 500 micrograms. It is also recommended that the elderly receive 500 micrograms a day. Because high dose folate supplements may mask the symptoms of vitamin B12 (cyanocobalamin) deficiencies (which are also common in the elderly), folic acid supplements should be given in conjunction with B12.
Side Effects: Extremely high intakes (1-5 mg/day) have been associated with masking the signs and symptoms of pernicious anemia (vitamin B12 deficiency).
The following abstracts and citations reflect the use of folic acid mentioned in the above overview of folic acid: prevention of neural tube defects, prevention and treatment of heart disease, and prevention and treatment of cancer. Many of the survey studies indicate the inadequate levels of folic acid, as well as other nutrients, in the general population. The recommendation may be for all women of childbearing age to consume at least 400 mg of folic acid each day, but unfortunately, that is not happening.
Folic Acid research shows the following:
1. Reduces risk of colorectal cancer
2. Prevents neural tube defects including brain and spinal cord deformities
3. Reduces homocysteine levels
4. Reduces risk of vascular disease
5. Reduces risk of
6. Improves endothelial function in coronary artery disease
7. Protects against breast cancer
8. Adequate amounts of folic acid intake are unlikely with a typical diet
9. Is an effective treatment in colorectal cancer
10. Enhances cardiovascular health
11. Is an effective treatment in neurological defects
12. Improves dysgeusia (absence of taste)
13. Low levels of folic acid may be associated with Alzheimer’s disease
14. Children with a family history of cardiovascular disease have low levels of folate
15. Lowers risk of atherosclerosis
16. May regulate cell proliferation in ulcerative colitis
Folic Acid Abstracts (14)
Folic Acid Citations (441)