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Folic Acid

Uses

Folic acid is a B vitamin needed for cell replication and growth. Folic acid helps form building blocks of DNA, the body’s genetic information, and building blocks of RNA, needed for protein synthesis in all cells. Therefore, rapidly growing tissues, such as those of a fetus, and rapidly regenerating cells, like red blood cells and immune cells, have a high need for folic acid. Folic acid deficiency results in a form of anemia that responds quickly to folic acid supplementation.

What Are Star Ratings?

This supplement has been used in connection with the following health conditions:

Used for Why
3 Stars
Abnormal Pap Smear
10 mg daily under medical supervision
Large amounts of folic acid have been shown to improve the abnormal Pap smears of some women who are taking birth control pills.

Large amounts of —10 mg per day—have been shown to improve the abnormal Pap smears of women who are taking birth control pills. Folic acid does not improve the Pap smears of women who are not taking oral contraceptives. High blood levels of folate (the food form of folic acid) have been linked to protection against the development of cervical dysplasia but these higher levels may only be a marker for eating more fruit and vegetables.

3 Stars
Birth Defects
At least 400 mcg daily
Supplementing with folic acid before and during the early weeks of pregnancy dramatically reduces the risk of neural tube defects.

Several studies and clinical trials have shown that 50% or more of NTDs can be prevented if women consume a -containing supplement before and during the early weeks of pregnancy. The United States Department of Public Health, the Centers for Disease Control and Prevention (CDC), and the March of Dimes recommend that all women who are capable of becoming pregnant supplement with 400 mcg folic acid daily. Daily supplementation prior to pregnancy is necessary because most pregnancies in the United States are unplanned and the protective effect of folic acid occurs in the first four weeks of fetal development, before most women know they are pregnant.

For women who have had a previous NTD-affected pregnancy, the CDC recommends daily supplementation with 4,000 mcg per day of folic acid. In a preliminary study, this amount of supplemental folic acid before and during early pregnancy resulted in a 71% reduction in the recurrence rate of NTDs.

3 Stars
Depression and Folic Acid Deficiency
See a doctor for evaluation
Taking folic acid can help correct deficiencies associated with depression.
A deficiency of the B vitamin can also disturb mood. A large percentage of depressed people have low folic acid levels. Folic acid supplements appear to improve the effects of lithium in treating manic-depressives. Depressed alcoholics report feeling better with large amounts of a modified form of folic acid. Anyone suffering from chronic depression should be evaluated for possible folic acid deficiency by a doctor. Those with abnormally low levels of folic acid are sometimes given short-term, high amounts of folic acid (10 mg per day).
3 Stars
Gingivitis
5 ml of a 0.1% solution used as a mouth rinse twice per day
Rinsing with a folic acid solution may help reduce inflammation and bleeding.

A 0.1% solution of used as a mouth rinse (5 ml taken twice a day for 30 to 60 days) has reduced gum inflammation and bleeding in people with gingivitis in double-blind trials. The folic acid solution is rinsed in the mouth for one to five minutes and then spit out. Folic acid was also found to be effective when taken in capsule or tablet form (4 mg per day), though in another trial studying pregnant women with gingivitis, only the mouthwash—and not folic acid in pill form—was effective. However, this may have been due to the body’s increased requirement for folic acid during pregnancy.

Phenytoin (Dilantin) therapy causes gum disease (gingival hyperplasia) in some people. A regular program of dental care has been reported to limit or prevent gum disease in people taking phenytoin. Double-blind research has shown that a daily oral rinse with a liquid folic acid preparation inhibited phenytoin-induced gum disease more than either folic acid in pill form or placebo.

3 Stars
High Homocysteine (Vitamin B6, Vitamin B12)
400 to 1,000 mcg of folic acid daily, 10 to 50 mg of vitamin B6 daily, and 50 to 300 mcg of vitamin B12 daily
Vitamin B6, folic acid, and vitamin B12 all play a role in converting homocysteine to other substances within the body and have consistently lowered homocysteine levels in trials.

Vitamin B6 , , and vitamin B12 all play a role in converting homocysteine to other substances within the body. By so doing, they consistently lower homocysteine levels in research trials, a finding that is now well accepted. Several studies have used (and some doctors recommend) 400–1,000 mcg of folic acid per day, 10–50 mg of vitamin B6 per day, and 50–300 mcg of vitamin B12 per day.

Of these three vitamins, supplementation lowers homocysteine levels the most for the average person. It also effectively lowers homocysteine in people on kidney dialysis. In 1996, the FDA required that all enriched flour, rice, pasta, cornmeal, and other grain products contain 140 mcg of folic acid per 3½ ounces. This level of fortification has led to a measurable decrease in homocysteine levels. However, even higher levels of food fortification with folic acid have been reported to be more effective in lowering homocysteine, suggesting that the FDA-mandated supplementation is inadequate to optimally protect people against high homocysteine levels. Therefore, people wishing to lower their homocysteine levels should continue to take folic acid supplements despite the FDA-mandated fortification program.

3 Stars
Neuropathy (Vitamin B6, Vitamin B12)
2,000 mcg methylcobalamin (B12); 3,000 mcg methylfolate (B9); and 35 mg pyridoxal 5-phosphate once to twice daily
B vitamins, and vitamin B12 in particular, may be helpful in treating various types of neuropathies. People with type 2 diabetes taking metformin should be monitored for B12 deficiency.
Vitamin B12 has demonstrated neuroprotective and analgesic effects and has been found to have benefits in treating peripheral neuropathy from various causes. Vitamin B12 deficiency is common in people with type 2 diabetes, and a widely used anti-diabetes medication, metformin, has been found to induce vitamin B12 deficiency. Vitamin B12 deficiency has been associated in some, but not all, studies with increased risk of diabetic neuropathy. A possible link between low folate levels and diabetic neuropathy has also been reported. Preliminary trials using combinations of active forms of oral vitamin B12, folate, and vitamin B6 found they have a positive effect on diabetic neuropathy symptoms and quality of life. In a comparison trial, vitamin B12 injections were found to be more effective than the pain medication, nortriptyline, for reducing diabetic neuropathy symptoms. One meta-analysis of 17 clinical trials found the combination of intramuscular or intravenous vitamin B12 plus intravenous alpha-lipoic acid may be more effective than vitamin B12 alone. The possible role of vitamin B12 and other B vitamins in preventing or treating chemotherapy-induced neuropathy is suggested by laboratory and animal research, but findings from human trials have not been conclusive.
3 Stars
Pregnancy and Postpartum Support
800 mcg daily, beginning before pregnancy
Supplementing with folic acid protects against the formation of birth defects, such as spina bifida. It also may lead to fewer infections for mothers and higher birth weight for babies.

Most doctors, many other healthcare professionals, and the March of Dimes recommend that all women of childbearing age supplement with 400 mcg per day of . Such supplementation could protect against the formation of neural tube defects (such as spina bifida) during the time between conception and when pregnancy is discovered.

The requirement for the B vitamin folic acid doubles during pregnancy, to 800 mcg per day from all sources. Deficiencies of folic acid during pregnancy have been linked to low birth weight and to an increased incidence of neural tube defects (e.g., spina bifida) in infants. In one study, women who were at high risk of giving birth to babies with neural tube defects were able to lower their risk by 72% by taking folic acid supplements prior to and during pregnancy. Several preliminary studies have shown that a deficiency of folate in the blood may increase the risk of stunted growth of the fetus. This does not prove, however, that folic acid supplementation results in higher birth weights. Although some trials have found that folic acid and iron, when taken together, have improved birth weights, other trials have found supplementation with these nutrients to be ineffective.

The relationship between folate status and the risk of miscarriage is also somewhat unclear. In some studies, women who have had habitual miscarriages were found to have elevated levels of homocysteine (a marker of folate deficiency). In a preliminary study, 22 women with recurrent miscarriages who had elevated levels of homocysteine were treated with 15 mg per day of and 750 mg per day of vitamin B6, prior to and throughout their next pregnancy. This treatment reduced homocysteine levels to normal and was associated with 20 successful pregnancies. It is not known whether supplementing with these vitamins would help prevent miscarriages in women with normal homocysteine levels. As the amounts of folic acid and vitamin B6 used in this study were extremely large and potentially toxic, this treatment should be used only with the supervision of a doctor.

In other studies, however, folate levels did not correlate with the incidence of habitual miscarriages.

Preliminary and double-blind evidence has shown that women who use a multivitamin-mineral formula containing folic acid beginning three months before becoming pregnant and continuing through the first three months of pregnancy have a significantly lower risk of having babies with neural tube defects (e.g., spina bifida) and other congenital defects.

In addition to achieving significant protection against birth defects, women who take supplements during pregnancy have been reported to have fewer infections, and to give birth to babies with higher birth weights and better Apgar scores. (An Apgar score is an evaluation of the well-being of a newborn, based on his or her color, crying, muscle tone, and other signs.) However, if a woman waits until after discovering her pregnancy to begin taking folic acid supplements, it will probably be too late to prevent a neural tube defect.

3 Stars
Schizophrenia and Folic Acid Deficiency
If deficient: 10 to 20 mg a day under medical supervision
People with schizophrenia may have a tendency to be deficient in folic acid and they may see improvements when given supplements.
People with schizophrenia may have a greater tendency to be deficient in than the general population, and they may show improvement when given supplements. A preliminary trial found that, among schizophrenic patients with folic acid deficiency, those given folic acid supplements had more improvement, and shorter hospital stays than those not given supplements. In a double-blind trial, a very high amount of folic acid (15 mg daily) was given to schizophrenic patients being treated with psychiatric medications who had low or borderline folic acid levels. The patients receiving the folic acid supplements had significant improvement, which became more significant over the six-month course of the trial. The symptoms of folic acid deficiency can be similar to those of schizophrenia, and two cases of wrong “schizophrenia” diagnoses have been reported. In one of these cases, an initial supplement of 20 mg daily of folic acid and a maintenance supplemental intake of 10 mg daily, led to resolution of symptoms.
3 Stars
Type 2 Diabetes
6 mg methylfolate daily
Folic acid supplementation may improve blood glucose control and insulin sensitivity in people with type 2 diabetes. Folic acid also lowers homocysteine levels and preliminary evidence suggests it may help to prevent and treat diabetes complications.

Folic acid, sometimes called vitamin B9, is needed along with vitamins B6 and B12 for healthy homocysteine metabolism. Elevated homocysteine levels have been associated with a range of chronic cardiovascular and neurological diseases. A meta-analysis pooled findings from 18 randomized controlled trials with a combined total of over 21,000 participants with type 2 diabetes. The analysis found folic acid supplementation lowered fasting blood glucose levels and reduced insulin resistance, but had no discernible effect on HbA1c, a marker of long-term blood glucose control.

Meta-analyses of studies have found high homocysteine levels are correlated with increased risk of diabetic retinopathy (damage to the visual center of the eye) and nephropathy (kidney damage). Because folic acid supplementation can lower high homocysteine levels in people with type 2 diabetes, it may be protective. In a preliminary trial, a B vitamin supplement providing 6 mg of methylfolate (the active form of folic acid), along with 70 mg of pyridoxal 5-phosphate (active vitamin B6) and 4 mg of methylcobalamin (active vitamin B12), per day improved retinal function and reduced retinal edema in participants with type 2 diabetes-related retinopathy. Several preliminary and placebo-controlled trials using the same B vitamin supplement indicate this combination may reduce symptoms of neuropathy related to type 2 diabetes.

2 Stars
Age-Related Cognitive Decline (Vitamin B12)
100 mcg per day of vitamin B12 and 400 mcg per day of folic acid
In a double-blind trial, supplementing with vitamin B12 and folic acid for 2 years slowed the rate of cognitive decline, compared with placebo, in elderly volunteers.
In a double-blind trial, supplementation with 100 mcg per day of vitamin B12 and 400 mcg per day of folic acid for 2 years slowed the rate of cognitive decline, compared with placebo, in elderly volunteers.
2 Stars
Age-Related Cognitive Decline (In people with high homocysteine)
800 mcg per day
Folic acid has been shown to slow the rate of cognitive decline in people with high homocysteine levels and in elderly people.

In a double-blind trial, elderly people with high homocysteine levels received 800 mcg of per day or a placebo for three years. Compared with placebo, folic acid supplementation significantly slowed the rate of decline of memory and of other measures of cognitive function.

2 Stars
Age-Related Cognitive Decline (Vitamin B6, Vitamin B12)
Refer to label instructions
In women with cardiovascular disease or related risk factors and low dietary intake of folic acid, vitamin B6, and vitamin B12, supplementing with a combination of these nutrients may protect against age-related cognitive decline.

In a study of female health professionals who had cardiovascular disease or cardiovascular disease risk factors, daily supplementation with folic acid (2.5 mg), vitamin B6 (50 mg), and vitamin B12 (1 mg) for 5.4 years had no effect on cognitive function. However, supplementation appeared to prevent age-related cognitive decline in the 30% of women who had low dietary intake of B vitamins.

Supplementation with homocysteine-lowering B vitamins (folic acid, vitamin B12, and vitamin B6) also slowed the rate of brain atrophy in elderly people who had mild cognitive impairment and high homocysteine levels.

2 Stars
Atherosclerosis
Consult a qualified healthcare practitioner
Blood levels of an amino acid called homocysteine have been linked to atherosclerosis and heart disease in most research. Taking folic acid may help lower homocysteine levels.

Blood levels of an amino acid called homocysteine have been linked to atherosclerosis and heart disease in most research, though uncertainty remains about whether elevated homocysteine actually causes heart disease. Although some reports have found associations between homocysteine levels and dietary factors, such as coffee and protein intakes, evidence linking specific foods to homocysteine remains preliminary. Higher blood levels of vitamin B6, vitamin B12, and are associated with low levels of homocysteine and supplementing with these vitamins lowers homocysteine levels.

While several trials have consistently shown that B6, B12, and folic acid lower homocysteine, the amounts used vary from study to study. Many doctors recommend 50 mg of vitamin B6, 100–300 mcg of vitamin B12, and 500–800 mcg of folic acid. Even researchers finding only inconsistent links between homocysteine and heart disease have acknowledged that a B vitamin might offer protection against heart disease independent of the homocysteine-lowering effect. In one trial, people with normal homocysteine levels had demonstrable reversal of atherosclerosis when supplementing B vitamins (2.5 mg folic acid, 25 mg vitamin B6, and 250 mcg of vitamin B12 per day). Similar results were seen in another study. In another study, supplementing with 5 mg per day of folic acid for 18 months reversed atherosclerosis in the carotid artery (an artery that supplies the brain) in people who had one or more risk factors for cardiovascular disease.

For the few cases in which vitamin B6, vitamin B12, and folic acid fail to normalize homocysteine, adding 6 grams per day of betaine (trimethylglycine) may be effective. Of these four supplements, folic acid appears to be the most important. Attempts to lower homocysteine by simply changing the diet rather than by using vitamin supplements have not been successful.

2 Stars
Breast Cancer
400 mcg daily
For women who drink alcohol, folic acid may reduce breast cancer risk by reversing the damaging effect alcohol has on DNA.

Among women who drink alcohol, those who consume relatively high amounts of folate from their diet have been reported to be at reduced risk of breast cancer, compared with women who drink alcohol but consumed less folate, according to a preliminary study. In a similar report, consumption of folic acid-containing supplements was associated with a lower risk of breast cancer in women who drank alcohol, compared with women who drank alcohol but did not take such supplements.

The damaging effect alcohol has on DNA—the material responsible for normal replication of cells—is partially reversed by folic acid. Therefore, a potential association between both dietary folate and folic acid supplements and protection against breast cancer in women who drink alcohol is consistent with our understanding of the biochemical effects of these substances. A combined intake from food and supplements of at least 600 mcg per day was associated with a 43% reduced risk of breast cancer in women who consumed 1.5 drinks per day or more, compared with women who drank the same amount but did not take folic acid-containing supplements.

2 Stars
Celiac Disease (Vitamin B6, Vitamin B12)
3 mg vitamin B6, 0.8 mg folic acid, and 0.5 mg vitamin B12
Daily supplementation with a combination of vitamin B6 (3 mg), folic acid (0.8 mg), and vitamin B12 (0.5 mg) have been shown to help relieve depression in people with celiac disease.
In one trial, 11 people with celiac disease suffered from persistent depression despite being on a gluten-free diet for more than two years. However, after supplementation with vitamin B6 (80 mg per day) for six months, the depression disappeared. Daily supplementation with a combination of vitamin B6 (3 mg), folic acid (0.8 mg), and vitamin B12 (0.5 mg) for 6 months also improved psychological well-being in people with long-standing celiac disease who had poor psychological well-being despite being on a strict gluten-free diet.
2 Stars
Celiac Disease
Consult a qualified healthcare practitioner
The malabsorption that occurs in celiac disease can lead to multiple nutritional deficiencies. Supplementing with folic acid may correct a deficiency.

The malabsorption that occurs in celiac disease can lead to multiple nutritional deficiencies. The most common nutritional problems in people with celiac disease include deficiencies of essential fatty acids, iron, vitamin D, vitamin K, calcium, magnesium, and .Zinc malabsorption also occurs frequently in celiac disease and may result in zinc deficiency, even in people who are otherwise in remission. People with newly diagnosed celiac disease should be assessed for nutritional deficiencies by a doctor. Celiac patients who have not yet completely recovered should supplement with a high-potency multivitamin-mineral. Some patients may require even higher amounts of some of these vitamins and minerals—an issue that should be discussed with their healthcare practitioner. Evidence of a nutrient deficiency in a celiac patient is a clear indication for supplementation with that nutrient.

After commencement of a gluten-free diet, overall nutritional status gradually improves. However, deficiencies of some nutrients may persist, even in people who are strictly avoiding gluten. For example, magnesium deficiency was found in 8 of 23 adults with celiac disease who had been following a gluten-free diet and were symptom-free. When these adults were supplemented with magnesium for two years, their bone mineral density increased significantly.

2 Stars
Halitosis and Gum Disease
Use 5 ml twice per day of a 0.1% solution
Folic acid is often recommended by doctors to help prevent and treat periodontitis and has been shown to reduce the severity of gingivitis when taken as a mouthwash.

Nutritional supplements recommended by some doctors for prevention and treatment of periodontitis include vitamin C (people with periodontitis are often found to be deficient),vitamin E, selenium, zinc, coenzyme Q10, and . Folic acid has also been shown to reduce the severity of gingivitis when taken as a mouthwash.

2 Stars
Heart Attack
500 to 800 mcg daily
Taking folic acid may reduce blood levels of homocysteine. High homocysteine levels have been linked to an increased heart attack risk.

High blood levels of the amino acid homocysteine have been linked to an increased risk of heart attack in most, though not all, studies. A blood test screening for levels of homocysteine, followed by supplementation with 400 mcg of folic acid and 500 mcg of vitamin B12 per day could prevent a significant number of heart attacks, according to one analysis. and vitamins B6 and B12 are known to lower homocysteine.

There is a clear association between low blood levels of folate and increased risk of heart attacks in men. Based on the available research, some doctors recommend 50 mg of vitamin B6, 100–300 mcg of vitamin B12, and 500–800 mcg of folic acid per day for people at high risk of heart attack.

2 Stars
Intermittent Claudication (Alpha-Linolenic Acid, Fish Oil, Oleic Acid, Vitamin B6, Vitamin E)
200 mg of EPA and 130 mg of DHA daily, plus small amounts of vitamin B6, folic acid, vitamin E, oleic acid, and alpha-linolenic acid
In one study, men with intermittent claudication who drank a milk product fortified with fish oil, vitamin B6, folic acid, vitamin E, oleic acid, and alpha-linolenic acid could walk further without pain than those who drank regular milk.

Men with intermittent claudication consumed a fortified milk product or regular milk daily for one year. The fortified product provided daily 130 mg of eicosapentaenoic acid and 200 mg of docosahexaenoic acid (EPA and DHA, two fatty acids in fish oil), small amounts of supplemental vitamin E, , and vitamin B6, and additional amounts of oleic acid and alpha-linolenic acid. Compared with regular milk, the fortified milk product significantly increased the distance the participants could walk before the onset of pain.

2 Stars
Macular Degeneration (Vitamin B6, Vitamin B12)
2.5 mg folic acid, 50 mg vitamin B6, and 1 mg vitamin B12
In a double-blind study of female health professionals who had cardiovascular disease or risk factors, daily supplementation with folic acid, vitamin B6, and vitamin B12 significantly decreased age-related macular degeneration.

In a double-blind study of female health professionals who had cardiovascular disease or cardiovascular disease risk factors, daily supplementation with folic acid (2.5 mg), vitamin B6 (50 mg), and vitamin B12 (1 mg) for 7.3 years significantly decreased the incidence of age-related macular degeneration. 

2 Stars
Migraine Headache (For a subset of people )
5 mg per day
Taking folic acid may improve migraines in people with high homocysteine levels and a certain genetic characteristic.
In a preliminary trial, supplementation with 5 mg of folic acid per day for six months completely eliminated recurrent migraine attacks in 10 of 16 children and reduced the number of attacks by 50 to 75% in the other six children. The children selected to be in this study had elevated homocysteine levels (which can be reduced by folic acid supplementation), as well as a certain genetic characteristic known as a polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene. Further research is needed to determine whether folic acid supplementation would be beneficial for migraine patients who do not have these specific characteristics.
2 Stars
Osteoporosis and High Homocysteine
5 mg with 1,500 mcg of vitamin B12 daily
Homocystinuria, a condition associated with high homocysteine levels, frequently causes osteoporosis. By lowering homocysteine levels, folic acid may help prevent osteoporosis.
, vitamin B6, and vitamin B12 are known to reduce blood levels of the amino acid homocysteine, and homocystinuria, a condition associated with high homocysteine levels, frequently causes osteoporosis. Therefore, some researchers have suggested that these vitamins might help prevent osteoporosis by lowering homocysteine levels. In a double-blind study of people who had suffered a stroke and had high homocysteine levels, daily supplementation with 5 mg of folic acid and 1,500 mcg of vitamin B12 for two years reduced the incidence of fractures by 78%, compared with a placebo. The reduction in fracture risk appeared to be due to an improvement in bone quality, rather than to a change in bone mineral density. However, supplementation with these vitamins did not reduce fracture risk in people who had only mildly elevated homocysteine levels and relatively high pretreatment folic acid levels. For the purpose of lowering homocysteine, amounts of folic acid and vitamins B6 and B12 found in high-potency B-complex supplements and multivitamins should be adequate.
2 Stars
Preeclampsia
5 mg daily
Supplementing with folic acid and vitamin B6 may lower homocysteine levels. Elevated homocysteine damages the lining of blood vessels and can lead to preeclamptic symptoms.

Women with preeclampsia have been shown to have elevated blood levels of homocysteine. Research indicates elevated homocysteine occurs prior to the onset of preeclampsia. Elevated homocysteine damages the lining of blood vessels, which can lead to the preeclamptic signs of elevated blood pressure, swelling, and protein in the urine.

In one preliminary trial, women with a previous pregnancy complicated by preeclampsia and high homocysteine supplemented with 5 mg of and 250 mg of vitamin B6 per day, successfully lowering homocysteine levels. In another trial studying the effect of vitamin B6 on preeclampsia incidence, supplementation with 5 mg of vitamin B6 twice per day significantly reduced the incidence of preeclampsia. Women in that study were not, however, evaluated for homocysteine levels. In fact, no studies have yet determined whether lowering elevated homocysteine reduces the incidence or severity of preeclampsia. Nevertheless, despite a lack of proof that elevated homocysteine levels cause preeclampsia, many doctors believe that pregnant women with elevated homocysteine should attempt to reduce those levels to normal.

2 Stars
Schizophrenia and High Homocysteine (Vitamin B6, Vitamin B12)
Take folic acid (2 mg), vitamin B6 (25 mg), and vitamin B12 (400 mcg) daily
People with schizophrenia who have high homocysteine levels may improve symptoms by supplementing with folic acid, vitamin B6, and vitamin B12.
In another double-blind study, daily supplementation with (2 mg), vitamin B6 (25 mg), and vitamin B12 (400 mcg) for three months improved symptoms of schizophrenia compared with a placebo. All of the participants in this study had elevated blood levels of homocysteine, which can be decreased by taking these three B vitamins. Based on this study, it would seem reasonable to measure homocysteine levels in people with schizophrenia and, if they are elevated, to supplement with folic acid, vitamin B6, and vitamin B12.
2 Stars
Sickle Cell Anemia and High Homocysteine
Consult a qualified healthcare practitioner
In one trial, patients with sickle cell anemia who were given folic acid plus aged garlic extract, vitamin C, and vitamin E saw significant improvement and less painful crises.

In a preliminary trial, 20 patients with sickle cell anemia were given either 1 mg of per day or folic acid plus 6 grams of aged garlic extract, 6 grams of vitamin C, and 1,200 mg of vitamin E per day for six months. Patients taking the combination had a significant improvement in their hematocrit (an index of anemia) and less painful crises than those taking just folic acid.

Preliminary research has found that patients with sickle cell anemia are more likely to have elevated blood levels of homocysteine compared to healthy people. Elevated homocysteine is recognized as a risk factor for cardiovascular disease. In particular, high levels of homocysteine in sickle cell anemia patients have been associated with a higher incidence of stroke. Deficiencies of vitamin B6, vitamin B12, and folic acid occur more frequently in people with sickle cell anemia than in others and are a cause of high homocysteine levels. A controlled trial found homocysteine levels were reduced 53% in children with sickle cell anemia receiving a 2–4 mg supplement of folic acid per day, depending on age, but vitamin B6 or B12 had no effect on homocysteine levels. A double-blind trial of children with sickle cell anemia found that children given 5 mg of folic acid per day had less painful swelling of the hands and feet compared with those receiving placebo, but blood abnormalities and impaired growth rate associated with sickle cell anemia were not improved. In the treatment of sickle cell anemia, folic acid is typically supplemented in amounts of 1,000 mcg daily. Anyone taking this amount of folic acid should have vitamin B12 status assessed by a healthcare professional.

2 Stars
Skin Ulcers
Consult a qualified healthcare practitioner
Large amounts of folic acid given both orally and by injection could promote healing of chronic skin ulcers due to poor circulation.

An older preliminary report suggested that large amounts of given both orally and by injection could promote healing of chronic skin ulcers due to poor circulation. No controlled research has further investigated this claim.

2 Stars
Thalassemia
If deficient: 250 to 1,000 mcg daily
Some studies have found people with thalassemia to be frequently deficient in folic acid, taking folic acid supplements may help.

Test tube studies have shown that propionyl-L-carnitine (a form of L-carnitine) protects red blood cells of people with thalassemia against free radical damage. In a preliminary study, children with beta thalassemia major who took 100 mg of L-carnitine per 2.2 pounds of body weight per day for three months had a significantly decreased need for blood transfusions. Some studies have found people with thalassemia to be frequently deficient in , vitamin B12, and zinc. Researchers have reported improved growth rates in zinc-deficient thalassemic children who were given zinc supplements of 22.5 to 90 mg per day, depending on age.Magnesium has been reported to be low in thalassemia patients in some, but not all, studies. A small, preliminary study reported that oral supplements of magnesium, 7.2 mg per 2.2 pounds of body weight per day, improved some red blood cell abnormalities in thalassemia patients.

2 Stars
Ulcerative Colitis
Consult a qualified healthcare practitioner
People with ulcerative colitis may be at a higher risk of colon cancer, supplementing with folic acid may reduce the risk.

UC is linked to an increased risk of colon cancer. Studies have found that people with UC who take supplements or who have high blood levels of folic acid have a reduced risk of colon cancer compared with people who have UC and do not take folic acid supplements. Although these associations do not prove that folic acid was responsible for the reduction in risk, this vitamin has been shown to prevent experimentally induced colon cancer in animals. Moreover, low blood folic acid levels have been found in more than half of all people with UC. People with UC who are taking the drug sulfasalazine, which inhibits the absorption of folic acid, are at a particularly high risk of developing folic acid deficiency. Folic acid supplementation may therefore be important for many people with UC. Since taking folic acid may mask a vitamin B12 deficiency, however, people with UC who wish to take folic acid over the long term should have their vitamin B12 status assessed by a physician.

Alcohol consumption is known to promote folic acid deficiency and has also been linked to an increased risk of colon cancer. People with UC should, therefore, keep alcohol intake to a minimum.

2 Stars
Vitiligo
Refer to label instructions
Studies have shown folic acid to be effective at skin repigmentation in people with vitiligo.

A clinical report describes the use of vitamin supplements in the treatment of vitiligo. and/or vitamin B12 and vitamin C levels were abnormally low in most of the 15 people studied. Supplementation with large amounts of folic acid (1–10 mg per day), along with vitamin C (1 gram per day) and intramuscular vitamin B12 injections (1,000 mcg every two weeks), produced marked repigmentation in eight people. These improvements became apparent after three months, but complete repigmentation required one to two years of continuous supplementation. In another study of people with vitiligo, oral supplementation with folic acid (10 mg per day) and vitamin B12 (2,000 mcg per day), combined with sun exposure, resulted in some repigmentation after three to six months in about half of the participants. This combined regimen was more effective than either vitamin supplementation or sun exposure alone.

1 Star
Alzheimer’s Disease
Refer to label instructions
Some researchers feel Alzheimer’s disease may be related to folic acid deficiency.

Some researchers have found an association between Alzheimer’s disease and deficiencies of vitamin B12 and ; however, other researchers consider such deficiencies to be of only minor importance. In a study of elderly Canadians, those with low blood levels of folate were more likely to have dementia of all types, including Alzheimer’s disease, than those with higher levels of folate. Little is known about whether supplementation with either vitamin would significantly help people with this disease. Nonetheless, it makes sense for people with Alzheimer’s disease to be medically tested for vitamin B12 and folate deficiencies and to be treated if they are deficient.

1 Star
Bipolar Disorder
Refer to label instructions
Folic acid deficiency is associated with both mania and depression. Getting enough folic acid helps the body manufacture serotonin and other neurotransmitters.

Both and vitamin B12 are used in the body to manufacture serotonin and other neurotransmitters. It is well known that deficiency of either nutrient is associated with depression. There is some evidence that patients diagnosed with mania are also more likely to have folate deficiencies than healthy controls. Other studies, however, have found that folic acid deficiency was not more common in bipolar patients taking lithium than in healthy people. Some studies have found that people who take lithium long term, and who also have high blood levels of folic acid, respond better to lithium. Not all studies have confirmed these findings, however. A double-blind study of patients receiving lithium therapy showed that the addition of 200 mcg of folic acid per day resulted in clinical improvement, whereas placebo did not.

1 Star
Colon Cancer
400 mcg daily
Folic acid appears to help prevent colon cancer, especially in people with ulcerative colitis and people who drink alcohol.

People with ulcerative colitis (UC) are at increased risk for colon cancer. Many patients with this disease take the drug sulfasalazine, which depletes folic acid. In a preliminary report, patients with long-standing UC who took folic acid supplements (at least 400 mcg per day) had a 62% lower incidence of colon cancer or precancerous changes in the colon, compared with those who did not supplement with folic acid. Although this difference was not statistically significant, the researchers recommended that people who take sulfasalazine should supplement with folic acid to potentially reduce the risk of colon cancer.

As dietary folate increases, the risks of precancerous polyps in the colon and colon cancer itself decrease, according to some, but not all, reports. In one study, women who had taken folic acid supplements had a statistically significant 75% reduction in the risk of colon cancer, compared with women not taking folic acid supplements, but only when they had been supplementing with folic acid for more than 15 years. In another report, the association between dietary folate and protection from precancerous polyps grew much stronger when use of folic acid supplements was considered (as opposed to studying only folate intake from food). However, one double-blind study found that supplementing with 1 mg of folic acid per day for three to eight years did not prevent recurrences of precancerous polyps in people who had already had at least one polyp.

The protection from colon cancer associated with high intake of folate has been reported to occur more in consumers of alcohol than in nondrinkers. This finding fits well with evidence that folate reverses damage to DNA caused by alcohol consumption. Damaged DNA can lead to abnormal cellular replication—a step toward cancer.

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Crohn’s Disease
Refer to label instructions
Folic acid is needed to repair intestinal cells damaged by Crohn’s disease. Supplementation may offset some of the deficiency caused by Crohn’s-related malabsorption.

Crohn’s disease often leads to malabsorption. As a result, deficiencies of many nutrients are common. For this reason, it makes sense for people with Crohn’s disease to take a high potency multivitamin-mineral supplement. In particular, deficiencies in zinc, , vitamin B12, vitamin D, and iron have been reported. Zinc, folic acid, and vitamin B12 are all needed to repair intestinal cells damaged by Crohn’s disease. Some doctors recommend 25 to 50 mg of zinc (balanced with 2 to 4 mg of copper), 800 mcg of folic acid, and 800 mcg of vitamin B12. Iron status should be evaluated by a doctor before considering supplementation.

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Depression
See a doctor for evaluation
Taking folic acid can help correct deficiencies associated with depression.
A deficiency of the B vitamin can also disturb mood. A large percentage of depressed people have low folic acid levels. Folic acid supplements appear to improve the effects of lithium in treating manic-depressives. Depressed alcoholics report feeling better with large amounts of a modified form of folic acid. Anyone suffering from chronic depression should be evaluated for possible folic acid deficiency by a doctor. Those with abnormally low levels of folic acid are sometimes given short-term, high amounts of folic acid (10 mg per day).
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Dermatitis Herpetiformis
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Supplementing with folic acid can counteract the nutrient deficiency that often occurs as a result of malabsorption.

People with DH frequently have mild malabsorption (difficulty absorbing certain nutrients) associated with low stomach acid (hypochlorhydria) and inflammation of the stomach lining (atrophic gastritis). Mild malabsorption may result in anemia and nutritional deficiencies of iron, ,vitamin B12, and zinc. More severe malabsorption may result in loss of bone mass. Additional subtle deficiencies of vitamins and minerals are possible, but have not been investigated. Therefore, some doctors recommend people with DH have their nutritional status checked regularly with laboratory studies. These doctors may also recommend multivitamin-mineral supplements and, to correct the low stomach acid, supplemental betaine HCl (a source of hydrochloric acid).

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Diarrhea
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Folic acid can help repair intestinal lining damage caused by acute diarrhea.

Acute diarrhea can damage the lining of the intestine. can help repair this damage. In one preliminary trial, supplementing with very large amounts of folic acid (5 mg three times per day for several days) shortened the duration of acute infectious diarrhea by 42%. However, a double-blind trial failed to show any positive effect with the same level of folic acid. Therefore, evidence that high levels of folic acid supplementation will help people with infectious diarrhea remains weak.

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Down Syndrome
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People with Down syndrome may be deficient in folic acid and may benefit from supplementation.

The red blood cells of people with Down syndrome are unusual in ways that suggest either vitamin B12 or deficiency. However, folic acid levels have been found to be normal in each of these studies, and only one study has found lower levels of vitamin B12 in Down syndrome as compared with healthy individuals. Intervention trials using either vitamin B12 or folic acid have not been done.

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Epilepsy
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Folic acid may help reduce epileptic seizure frequency, people taking anticonvulsant medications should talk to their doctor before deciding whether to use folic acid.

supplementation (5 mg per day) was reported to reduce epileptic seizure frequency, though the effect was not significantly better than with placebo. Folic acid supplementation of as little as 800 mcg per day has also been reported to interfere with the action of anticonvulsant medications, resulting in an increase in the frequency and/or severity of seizures; this effect occurs only in a small number of cases. People taking anticonvulsant medications should consult with the prescribing physician before deciding whether to use folic acid.

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Gingivitis
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In pill form, folic acid may improve gingivitis symptoms, although one study found the mouth rinse form to be more effective.

A 0.1% solution of used as a mouth rinse (5 ml taken twice a day for 30 to 60 days) has reduced gum inflammation and bleeding in people with gingivitis in double-blind trials. The folic acid solution is rinsed in the mouth for one to five minutes and then spit out. Folic acid was also found to be effective when taken in capsule or tablet form (4 mg per day), though in another trial studying pregnant women with gingivitis, only the mouthwash—and not folic acid in pill form—was effective. However, this may have been due to the body’s increased requirement for folic acid during pregnancy.

Phenytoin (Dilantin) therapy causes gum disease (gingival hyperplasia) in some people. A regular program of dental care has been reported to limit or prevent gum disease in people taking phenytoin. Double-blind research has shown that a daily oral rinse with a liquid folic acid preparation inhibited phenytoin-induced gum disease more than either folic acid in pill form or placebo.

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HIV and AIDS Support
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Low folic acid levels are also common in HIV-positive people, supplementing may help correct a deficiency.

In HIV-positive people with B-vitamin deficiency, the use of B-complex vitamin supplements appears to delay progression to and death from AIDS. Thiamine (vitamin B1) deficiency has been identified in nearly one-quarter of people with AIDS. It has been suggested that a thiamine deficiency may contribute to some of the neurological abnormalities that are associated with AIDS. Vitamin B6 deficiency was found in more than one-third of HIV-positive men; vitamin B6 deficiency was associated with decreased immune function in this group. In a population study of HIV-positive people, intake of vitamin B6 at more than twice the recommended dietary allowance (RDA is 2 mg per day for men and 1.6 mg per day for women) was associated with improved survival. Low blood levels of and vitamin B12 are also common in HIV-positive people.

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Lung Cancer
Refer to label instructions
Together, folic acid and vitamin B12 help cells replicate normally. In one trial, smokers with precancerous lung changes who were given folic acid and vitamin B12 saw a significant reversal of their condition.

and vitamin B12 work together in the body to help cells replicate normally. In a double-blind trial, smokers with precancerous changes in the lungs were given a placebo or the combination of 10,000 mcg of folic acid and 500 mcg of vitamin B12 per day for four months. A significant reversal of precancerous changes occurred in those given vitamin supplements compared with those given the placebo. No trials have investigated whether either vitamin given alone or the combination of both vitamins would help to treat people who already have lung cancer.

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Peripheral Vascular Disease
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As with other vascular diseases, people with thromboangiitis obliterans are more likely to have low levels of folic acid. Supplementing with folic acid may help correct a deficiency.

As with other vascular diseases, people with TAO are more likely to have high levels of homocysteine and low levels of . However, no research has tested folic acid as prevention or treatment for this disease.

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Psoriasis
Only for people who are not taking prescription drugs such as methotrexate that interfere with folic acid metabolism
High amounts of folic acid have been shown to improve psoriasis.

antagonist drugs have been used to treat psoriasis. In one preliminary report, extremely high amounts of folic acid (20 mg taken four times per day), combined with an unspecified amount of vitamin C, led to significant improvement within three to six months in people with psoriasis who had not been taking folic acid antagonists;those who had previously taken these drugs saw a worsening of their condition.

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Restless Legs Syndrome
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People with familial restless leg syndrome appear to have an unusually high requirement for folic acid. Supplementing with folic acid may help relieve uncomfortable sensations.

In some people with RLS, the condition may be genetic. People with familial RLS appear to have inherited an unusually high requirement for . Although not all people with RLS suffer from uncomfortable sensations, folate-deficient people with this condition always do. In one report, 45 people were identified to be from families with folic acid-responsive RLS. The amount of folic acid required to relieve their symptoms was extremely large, ranging from 5,000 to 30,000 mcg per day. Such amounts should only be taken under the supervision of a healthcare professional.

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Seborrheic Dermatitis
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Supplementing with folic acid has been shown to improve adult seborrheic dermatitis.

One physician reported that injections of B-complex vitamins were useful in the treatment of seborrheic dermatitis in infants. A preliminary trial found that 10 mg per day of was helpful in 17 of 20 cases of adult seborrheic dermatitis. However, this study also found that oral folic acid did not benefit infants with cradle cap. A preliminary study found that topical application of vitamin B6 ointment (containing 10 mg B6 per gram of ointment) to affected areas improved adult seborrheic dermatitis. However, oral vitamin B6 (up to 300 mg per day) was ineffective. Injections of vitamin B12 were reported to improve in 86% of adults with seborrheic dermatitis in a preliminary trial. Oral administration of vitamin B12 for seborrheic dermatitis has not been studied.

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Stroke and High Homocysteine
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Elevated blood levels of homocysteine have been linked to stroke risk in most studies. Supplementing with folic acid may lower homocysteine levels and reduce stroke risk.

Elevated blood levels of homocysteine, a toxic amino acid byproduct, have been linked to risk of stroke in most studies. Supplementation with , vitamin B6, and vitamin B12 generally lowers homocysteine levels in humans. In a pooled analysis (meta-analysis) of eight randomized trials, folic acid supplementation in varying amounts (usually 0.5 mg to 5 mg per day) reduced stroke risk by 18%.

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Thromboangiitis Obliterans
Refer to label instructions
As with other vascular diseases, people with thromboangiitis obliterans are more likely to have low levels of folic acid. Supplementing with folic acid may help correct a deficiency.

As with other vascular diseases, people with TAO are more likely to have high levels of homocysteine and low levels of . However, no research has tested folic acid as prevention or treatment for this disease.

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