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How Folate Works


Folate Deficiency
The RDA for folate is 400 micrograms (mcg) for all adults. Pregnant women require 600 mcg because so many new cells are being made. The average American diet provides about 200 to 250 mcg of the vitamin. Most prenatal supplements contain 800 mcg.

Foods contain folate both in free form and bound to amino acids. To absorb folate, however, it must be freed. Vitamin B12 helps to free the folate for absorption.

Most prenatal supplements contain 800 mcg of folate, which is 200 more than pregnant women require.
©2007 Publications International, Ltd.
Most prenatal supplements contain
800 mcg of folate, which is 200 more
than pregnant women require.

Folate deficiency can result from either inadequate intake or reduced absorption. It can also occur during periods of increased need, such as multiple pregnancies, cancer, or severe burns.

Some medications can interfere with the body's ability to use this vitamin. These medications include aspirin, oral contraceptives, and drugs used to treat convulsions, psoriasis, and cancer. In addition, abuse of alcohol can damage the intestine so that less folate is absorbed.

Symptoms of folate deficiency include diarrhea; weight loss; anemia; and a red, sore, and swollen tongue. The macrocytic anemia caused by folate deficiency is prevalent in underdeveloped countries and among low-income pregnant women. Macrocytic anemia is rare in the United States because of the routine use of supplements during pregnancy.

Experts now emphasize the importance of folate supplementation in the very early stages of pregnancy because the vitamin plays an important role in early fetal development.

Inadequate amounts during the first few weeks of pregnancy can cause birth defects of the spinal cord, known as neural tube defects. These can manifest as spina bifida, openings in the spinal cord, or in severe cases, as anencephaly, the absence of a brain.

Because folate is so important at a time when many women might not even know they are pregnant, women planning to conceive -- and any women capable of becoming pregnant -- should be sure they are getting enough folate. If not, a supplement is appropriate.

Despite the serious drawbacks of folate deficiency, there's disagreement on how much is enough. The next page details the arguments about the proper level of folate supplementation.

Folate is just one of the many vitamins that are part of a healthy diet. Check out the following links to learn more:
  • Vitamin B12, which helps folate make cells, works differently than any other vitamin. Learn the details at How Vitamin B12 Works.
  • Vitamin A plays an essential role in eyesight. Learn how it helps us to see, even in the dark, at How Vitamin A Works.
  • Found mostly in protein, vitamin B3 keeps us strong. How Vitamin B3 Works explains what happens if you don't get enough of it.
  • Your body can make its own vitamin D if you get enough sunshine. Learn the details at How Vitamin D Works.
  • Biotin aids in metabolism, turning food into energy. Learn more at How Biotin Works.
  • To learn about the many vitamins in our diet, how much you should be eating, and where to find them, go to our general Vitamins page.
  • If you were looking for the best prices on B vitamin supplements, click here.
This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.