Vitamin B-9 (Folic Acid)

Folate and folic acid are forms of a water-soluble B vitamin. Folate occurs naturally in food, and folic acid is the synthetic form of this vitamin. Since 1998, folic acid has been added to cold cereals, flour, breads, pasta, bakery items, cookies, and crackers, as required by federal law. Foods that are naturally high in folate include leafy vegetables (such as spinach, broccoli, and lettuce), okra, asparagus, fruits (such as bananas, melons, and lemons) beans, yeast, mushrooms, meat (such as beef liver and kidney), orange juice, and tomato juice.

Folic acid is used for preventing and treating low blood levels of folate (folate deficiency), as well as its complications, including "tired blood" (anemia) and the inability of the bowel to absorb nutrients properly. Folic acid is also used for other conditions commonly associated with folate deficiency, including ulcerative colitis, liver disease, alcoholism, and kidney dialysis.

Women who are pregnant or might become pregnant take folic acid to prevent miscarriage and "neural tube defects," birth defects such as spina bifida that occur when the fetus's spine and back do not close during development. Women also take folic acid before and during pregnancy to prevent other complications such as increased blood pressure during pregnancy and to improve the growth and development of the child.

Some people use folic acid to prevent various types of cancer, including colon cancer or cervical cancer, as well as to reduce nerve pain in people with high levels of blood sugar (diabetes). It is also used to prevent heart disease and stroke, as well as to reduce blood levels of a chemical called homocysteine. High homocysteine levels might be a risk for heart disease.

Folic acid is used for pimples on the skin, gum inflammation, memory loss, Alzheimer's disease, age-related hearing loss, preventing the eye disease age-related macular degeneration (AMD), reducing signs of aging, weak bones (osteoporosis), a disorder that causes a strong urge to move ones legs (restless legs syndrome; RLS), sleep problems, depression or feeling down, seizures, nerve pain, muscle or bone pain, AIDS, a skin disease called vitiligo, an inflammatory disease called gout, and an inherited disease called Fragile-X syndrome. It is also used for reducing harmful side effects of treatment with the medications nitroglycerin, lometrexol or methotrexate. Folic acid is used to help the body make sperm.

Some people apply folic acid directly to the gum for treating gum infections.

If it is difficult for the patient to take folic acid by mouth, it is sometimes given with a needle for preventing and treating low blood levels of folate (folate deficiency). Folic acid is also given with a needle for chronic fatigue syndrome, a condition with chronic fever, aches, and tiredness.

Folic acid is often used in combination with other B vitamins.

How does it work?

Folate is needed for the proper development of the human body. It is involved in producing the genetic material called DNA and in numerous other bodily functions.

Folate deficiency.
Kidney disease.
High amounts of homocysteine in the blood (hyperhomocysteinemia).
Reducing harmful effects of a medicine called methotrexate.
Birth defects (neural tube defects).
Age-related vision loss (age-related macular degeneration).
Depression.
High blood pressure.
Gum problems due to a drug called phenytoin.
Gum disease during pregnancy.
A skin discoloration disorder called vitiligo.
Acne.
Alzheimer's disease.
Autism.
Beta-thalassemia.
Cervical cancer.
Esophageal cancer.
High amounts of homocysteine in the blood caused by the drug fenofibrate.
Stomach cancer.
Gout.
Hearing loss.
Low birth weight.
Male infertility.
A type of skin cancer called melanoma.
Pancreatic cancer.
Cancer of the throat.
A disorder that causes a strong urge to move ones legs (restless legs syndrome; RLS).
Cancer due to a disease called ulcerative colitis.
Alcoholism.
Liver disease.

Adults

By Mouth:

For folic acid deficiency: the typical dose is 250 mcg (micrograms) to 1 mg (milligrams) per day.

For preventing neural tube defects: at least 400 mcg of folic acid per day from supplements or fortified food should be taken by women capable of becoming pregnant and continued through the first month of pregnancy. Women with a history of previous pregnancy complicated by such neural tube defects usually take 4 mg per day beginning one month before and continuing for three months after conception.

For reducing colon cancer risk: 400 mcg per day.
For treating high levels of homocysteine in the blood:

o 200 mcg to 15 mg/day has been used, although 800 mcg to 1 mg/day appears to be more effective.

In people with end-stage renal disease, high homocysteine levels may be more difficult to treat, and doses of 800 mcg to 40 mg/day have been used. Other dosage plans such as 2.5-5 mg 3 times weekly have also been used. Doses higher than 15 mg daily do not seem to be more effective.

For improving the response to medications for depression: 200-500 mcg daily has been used.

For vitiligo: 5 mg is typically taken twice daily.

For reduction of toxicity associated with methotrexate therapy for rheumatoid arthritis (RA) or psoriasis: 1 mg/day is probably enough, but up to 5 mg/day may be used.

For preventing macular degeneration: folic acid 2.5 mg, vitamin B12 (cyanocobalamin) 1000 mg, and vitamin B6 (pyridoxine) 50 mg daily.

Applied to the Skin:

For gum problems in pregnancy: a mouthwash containing folic acid has been used twice daily for one minute.

Children

By Mouth:

For gum problems due to a drug called phenytoin (6-15 years): folic acid 500 mcg daily has been used.

Folic acid is SAFE for most people when taken by mouth or injected into the body. Most adults do not experience any side effects when used in doses less than 1 mg daily.

Folic acid is POSSIBLY UNSAFE when taken by mouth in large doses, long-term. High doses of folic acid might cause abdominal cramps, diarrhea, rash, sleep disorders, irritability, confusion, nausea, stomach upset, behavior changes, skin reactions, seizures, gas, excitability, and other side effects.

There is some concern that taking too much folic acid for a long period of time might cause serious side effects. Some research suggests that taking folic acid in doses of 800 mcg to 1.2 mg might increase the risk of heart attack in people who have heart problems. Other research suggests that taking these high doses might also increase the risk of cancer such as lung or prostate cancer

Pregnancy and breast-feeding: Folic acid is LIKELY SAFE when taken by mouth appropriately during pregnancy and breast-feeing. Taking 300-400 mcg of folic acid daily is commonly used during pregnancy to prevent birth defects.

Procedures to widen narrowed arteries (angioplasty): Using folic acid, vitamin B6, and vitamin B12 intravenously (by IV) or by mouth might worsen narrowed arteries. Folic acid should not be used by people recovering from this procedure.

Cancer: Early research suggests that taking 800 mcg to 1 mg of folic acid daily might increase the risk of cancer. Until more is known, people with a history of cancer should avoid high doses of folic acid.

Heart disease: Early research suggests that taking folic acid plus vitamin B6 might increase the risk for heart attack in people with a history of heart disease.

Malaria: Early research suggests that taking folic acid plus iron might increase the risk of death or need for treatment in hospital in areas of the world where malaria is common.

Anemia caused by vitamin B12 deficiency: Taking folic acid might mask anemia caused by vitamin B12 deficiency and delay appropriate treatment.

Seizure disorder: Taking folic acid supplements might make seizures worse in people with seizure disorders, particularly in high doses.