Folic acid, also called folate or folacin, is a B vitamin with a solid reputation for protecting against birth defects and heart disease. If adults were to get an adequate amount of this vitamin, it is estimated that 50,000 deaths from cardiovascular disease could be prevented each year in the United States alone. Moreover, common birth defects could be cut nearly in half. Other ailments, such as depression, Alzheimer's disease, and certain types of cancer may respond to the effects of folic acid as well.
Because the body can't retain this water-soluble vitamin for long--any excess is excreted in the urine--many people have a folic acid deficiency. To make matters worse, half of the folic acid content in foods can be lost through cooking, processing, or long-term storage. This makes supplements (particularly a high-potency multivitamin or a B-vitamin complex) one of the most practical ways to get enough of this vital nutrient.
Folic acid is involved in every bodily function that requires cell division. It is used to generate red blood cells, help wounds heal, build muscle, and produce brain and nervous-system chemicals. It should always be taken in combination with vitamin B12, because taking only one of these B vitamins can mask a deficiency in the other. Folic acid is often included in vitamin B-complex supplements.
Specifically, folic acid may help to:
Lower the risk of heart disease and stroke. Folic acid appears to regulate the body's production and use of homocysteine, an amino acid-like compound that in excess amounts can contribute to the buildup of dangerous plaque in the blood vessels (a precursor of heart disease and stroke). In addition, a small Dutch study has recently shown that by lowering blood levels of homocysteine and improving the ability of the blood vessels to dilate, folic acid may reduce cardiovascular risk in those with a family history of high cholesterol. For heart disease prevention, the vitamin is often taken as part of a B-complex supplement.
Improve fertility and prevent neurological birth defects. Taken as part of a B-complex vitamin that contains biotin and vitamin B12, folic acid can strengthen the reproductive system in women having trouble conceiving. Folic acid also ensures normal cell replication and contributes to the formation of DNA and RNA, making it essential for healthy fetal development. If a woman is taking adequate amounts of folic acid at the time she conceives, and during the first three months of pregnancy, the risk of giving birth to a baby with spina bifida or certain other serious birth defects can be decreased by nearly 50%.
Combat depression. Because folic acid is often deficient in those who are depressed, a supplement may help. Studies of depressed people with low blood levels of folic acid show that taking it in supplement form can improve the effectiveness of antidepressants. Folic acid also appears to reduce the high levels of homocysteine associated with some forms of depression. Taking folic acid as part of a B-complex vitamin supplement is often recommended to combat depression.
Reduce the incidence of certain cancers. Some studies suggest that folic acid can help prevent cancers of the lung, cervix, rectum, and colon. Just how the body might use the vitamin to help stave off cancer is unclear, but it is theorized that folic acid keeps cells from mutating and proliferating. More study is needed in this area.
Guard against Alzheimer's disease. Preliminary research indicates a link between low blood levels of this B vitamin and Alzheimer's disease. In a recent study, the most advanced cases of this memory-robbing disease were associated with the lowest levels of folic acid. Conversely, people with the highest level of cognitive functioning also had the highest levels of folic acid. Additional research is needed to determine the role of folic acid in the development of Alzheimer's. Meanwhile, it's probably wise for those suffering from this condition to take a B-complex supplement containing folic acid.
Retard the symptoms of gum disease. When applied topically to the gums, folic acid in liquid form can often help to reduce gum inflammation and bleeding and promote faster healing.
Fight anemia. Taking folic acid in tandem with vitamin B12 may be beneficial if you have anemia caused by a deficiency of either one of these vitamins. Together they work to boost the production of red blood cells. Be sure to always take the two vitamins together, and under a doctor's supervision, because a high intake of one can mask a deficiency of the other. Vitamin B12 deficiency can cause irreversible nerve damage and dementia.
Slow the progress of multiple sclerosis. Some studies show that MS patients have low levels of vitamin B12 or have trouble processing it well. Taking a vitamin B complex, plus extra vitamin B12 and folic acid, can help to maintain nerve structure and function in those with this disabling nerve disorder.
Note: Folic acid has also been found to be useful for a number of other disorders, particularly when taken in combination with B12 or in a B-complex supplement. For information on these additional ailments, see our Dosage Recommendations Chart for Folic acid.
The RDA for folic acid is 400 mcg daily.
If You Get Too Little
A moderate folic acid deficiency exhibits no symptoms, but it does increase vulnerability to heart disease. In women, a deficiency can increase the risk of bearing a child with birth defects. In rare cases, people can develop a severe deficiency, which may lead to a serious form of anemia called megaloblastic anemia, and to chronic diarrhea, a sore red tongue, and poor growth in children. Those most susceptible to a severe deficiency are alcoholics, people on certain types of medications (for epilepsy or cancer), and people with disorders that affect their ability to absorb nutrients, such as Crohn's disease or celiac sprue.
If You Get Too Much
According to the National Academy of Sciences, the daily intake of folic acid in adults should not exceed 1,000 mcg. Very high doses of this vitamin offer no additional therapeutic value. They can also trigger seizures in people with epilepsy.
General Dosage Information
Special tips: Always take an individual folic acid supplement with an extra 1,000 mcg of vitamin B12.
--Taking folic acid in the sublingual (under the tongue) form enhances absorption.
--As a break from pills, you can also try mixing folic acid powder into a shake or fruit juice.
For general health: If you are an adult make sure you get 400 to 800 mcg folic acid daily through foods and supplements.
For heart disease prevention, aging, and multiple sclerosis: Take 400 mcg folic acid a day.
For female infertility and depression: Take one B-50 complex pill with 400 mcg folic acid; 50 mcg vitamin B12 and biotin; and 50 mg all other B vitamins.
For women trying to become pregnant and to prevent birth defects: Take 800 mcg a day. Because a considerable amount of fetal development will have occured before a pregancy test registers as positive, it's a good idea to start taking your folate supplement at least three months before you start trying to get pregnant.
For cancer prevention: Take 400 to 800 mcg a day.
For Alzheimer's disease prevention: Take one B-100 complex pill with 400 mcg folic acid; 100 mcg vitamin B12 and biotin; and 100 mg all other B vitamins. Also take an extra 50 mg of vitamin B6.
For gum disease: Every other day apply folic acid liquid to the gums with a cotton swab, then gently brush vitamin C powder along the gum line with a very soft toothbrush. On alternate days break open a vitamin E capsule and rub the oil onto the gums.
For anemia: Take 400 mcg folic acid and 1,000 mcg B12 twice a day for one month.
Be sure to check out our Dosage Recommendations Chart for Folic Acid, which lists therapeutic dosages for specific ailments at a glance.
Adults should take no more than 1,000 mcg of folic acid a day.
Folic acid can be taken with or without food, at any time of the day.
Good food sources of folic acid include asparagus; beets; broccoli; avocados; Brussels sprouts; beans, dried; chickpeas; soybeans; lentils; oranges; peas, fresh; turkey; cabbage, savoy; bok choy; and spinach.
When taking a folic acid supplement for any reason, combine it with an additional 1,000 mcg of vitamin B12 to prevent a deficiency of either vitamin (one can mask a deficiency in the other). Combination supplements containing both are available, and may be less expensive than buying each vitamin separately. Folic acid also comes as part of a B-complex vitamin.
Taking folic acid supplements may be more effective than getting it from natural food sources. One study showed that people who got 400 mcg of folic acid a day from supplements, or from foods fortified with this vitamin, experienced increased folic acid blood levels; those who got the same dose from food naturally high in folic acid did not.
Supplements are especially important for people who may not eat a diet with sufficient folic acid or who lose the ability to absorb it from food. The elderly are at risk, as well as smokers, alcoholics, people with digestive disorders, vegetarians, and women who are pregnant or lactating.
If you take medication to control seizures, consult your doctor before taking folic acid supplements. They can reduce the effectiveness of certain anticonvulsant drugs.
Note: For information on interactions with specific generic drugs, see our WholeHealthMD Drug/Nutrient Interactions Chart.
Always take vitamin B12 when taking folic acid. When taken on its own, folic acid can hide a type of anemia caused by B12 deficiency, which, if not detected, can lead to irreversible nerve damage and dementia.
If you have a medical or psychiatric condition, or if you are subject to seizures, talk to your doctor before taking folic acid supplements.