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Vitamin B9 – Folate

What is folic acid/vitamin B9?

Vitamin B9, more commonly known as folate or folic acid, is a water-soluble vitamin that is part of the B vitamin family. B vitamins/folate help support adrenal function, help calm and maintain a healthy nervous system, and are necessary for key metabolic processes. Folate occurs naturally in foods, while folic acid is the synthetic form of folate.

Why is vitamin B9 necessary?

Vitamin B9 is essential for human growth and development, encourages normal nerve and proper brain functioning, and may help reduce blood-levels of the amino acid homocysteine (elevated homocysteine levels have been implicated in increased risk of heart disease and stroke). Folic acid or folate may also help protect against cancers of the lung, colon, and cervix, and may help slow memory decline associated with aging.

Pregnant women have an increased need for folic acid: it supports the growth of the placenta and fetus, and helps to prevent several types of birth defects, especially those of the brain and spine. Pregnant women and women of child-bearing age should take extra caution to get enough folic acid (see below for recommended amounts).

What are the signs of a folic acid deficiency?

Deficiency has been linked to birth defects, low birth weight, pregnancy loss, depression, memory loss, and cervical dysplasia. Alcoholics, pregnant women, and people living in institutional settings are at a higher risk of vitamin B9 or folate deficiency.

How much, and what kind of folic acid does an adult need?

The daily U.S. Recommended Dietary Allowance (RDA) is 400 micrograms for adults. Dr. Weil recommends 400 mcg per day as part of a B-Complex supplement that contains a full spectrum of B vitamins, including biotin, thiamin, B12, riboflavin and niacin.He recommends that women who are pregnant or nursing discuss their vitamin B9 dosage with their obstetrician/gynecologist.

How much folate does a child need?

The daily RDA for children from 0 to 6 months is 65 micrograms of folic acid; 7-12 months, 80 micrograms; 1-3 years, 150 micrograms; 4-8 years, 200 micrograms; 9-13 years, 300 micrograms.

How do you get enough vitamin B9 from foods?

Spinach, green vegetables and beans are good sources, as are fortified products such as orange juice, baked goods, and cereals. Other natural sources of folate include asparagus, bananas, melons, lemons, legumes, yeast, and mushrooms.

Are there any risks associated with too much vitamin B9 or folic acid?

Folic acid has few side effects, even when taken in high amounts. Although the folic acid itself is not a problem, supplemental folic acid can mask symptoms of pernicious anemia, a potentially fatal disease which is caused by a deficiency of vitamin B12. Very high doses (above 15,000 mcg) can cause stomach problems, sleep disturbances, skin reactions, and seizures. 

Are there any other special considerations with folic acid?

The absorption of supplemental folic acid is reduced slightly when taken with food. Folic acid absorption or depletion may occur in those who use alcohol excessively, who use large amounts of antacids, are prescribed antiobiotics, who take aspirin chronically and in large doses, or who take oral contraceptives. In addition, folic acid, when taken along with vitamin B12, may increase the risk of masking an underlying vitamin B12 deficiency. Caution is advised when taking both of these vitamins together.


Are you getting the supplements you need?
Everyone’s dietary needs are different based on a number of factors including lifestyle, diet, medications and more. To find out which supplements are right for you, take the Weil Vitamin Advisor. This 3-step questionnaire requires just minutes to complete, and generates a free, no-obligation vitamin and nutritional supplement recommendation that is personalized to meet your unique nutritional needs.