Folate, also known as folic acid, vitamin B9, plays a key role in cell division in human body. It is an important essential in prenatal vitamins. In some researches, we found it reduce the risk of heart disease, and it is helpful lessen the incidence rate of some cancers.
You can find the folate from dark green leafy vegetables, and oranges. These are natural good source of folate, but the synthetic source of folic acid seems has a twice absorption and a more bioavailability as well as the natural source folate.
There are two new synthetic source of folate products, Metafolin and Quatrefolic were accepted by FDA individually in 2001 and 2010. With stabilized form in Metafolin (calcium salt, Metafolin® is a registered trademark of Merck KGaA, Darmstadt, Germany) and Quatrefolic (glucosamine salt, Quatrefolic® is a registered trademark of Gnosis S.p.A. Corporation), they have an active compound, called L-5-methylfolate, which is same created in the body as folate and folic acid does. People with common genetic mutations were suggested to take these new forms, as it was proved to have more effectiveness than folic acid in a short term.
Benefits for pregnant women
It is helpful to reduce the risk of spina bifida in fetus if folate consumed in prenatal vitamins by pregnant women. Folate is also proved to lessen the occurrence of leukemia and some other defects among infants.
A research from the Norwegian Institute of Public Health in Oslo announced that, the women took folic acid (400 mcg per day) from 4 weeks before to 8 weeks after their pregnancy had a 39% lower risk of autistic disorder in children, compared to the children whose mothers didn’t have any folic acid supplement.
But many pregnancies are unplanned, it is difficult to recommend a folic acid supplement before conception. Most of time the neural tube defects may have already occurred, because the average of first antenatal visit normally is 9 weeks.
Since 1998, folic acid were fortificated in cereal grains mandatorily and as a result, there is less than 1% of people in Americans have folate deficiency. Then over 50 countries around the world have followed this mandatory fortification with folic acid.
As a result, the RDAs doses are based on the regular food sources, if you are taking folic acid in prenatal vitamins or fortificated food, which are twice absorbs in the body, you have to take 1/2 following RDAs:
For Children 1 – 3 years old: 150 mcg
Children 4 – 8 years old: 200 mcg
Children 9 – 13 years old: 300 mcg
Over 14 years old: 400 mcg
Pregnant women: 600 mcg
Lactating women: 500 mcg
The ULs of folate (total amount from fortified food and supplements):
For Children 1 – 3 years old: 300 mcg
Children 4 – 8 years old: 400 mcg
Children 9 – 13 years old: 600 mcg
Children 14 – 18 years old: 800 mcg
Individual over 19 years old: 1,000 mcg
There are increasing concerns for the folic acid intake 1000 mcg per day from supplement, associated with a more than doubling risk of prostate cancer. Meanwhile, the folate from natural sources was not found any risk raised.
Although folate may reduce the incidence rate of cancer, e.g. the notably colorectal cancer, there are some concerns about the exceed folic acid from supplements and fortificated foods may increase the risk of cancerous tumors or pre-cancerous. For example, it was observed that the risk of colorectal cancer was increased after the country began to fortify the wheat flour with folic acid in Chile and other countries in 2009.
But according to a recent study in U.S. (2011), there was no significant association found between the colorectal cancer and folic acid serving. In contrast, this study found a 19% reducing in the risk of colon cancer comparing the people took the highest dose of folic acid (including both of the natural folate and folic acid) to those with the lowest dose intake.
Update: Jun 11, 2017:
As FDA changed the DVs (Daily Values) standard for many vitamins and minerals, especially for folate, one new DFE – Dietary Folate Equivalents) was introduced for the label in supplement product, a lot of dietary supplements in the market are actually exceed for the upper limit (ULs) for folate intake.
If the folate in synthetic form (folic acid or Methylfolate) then it should be marked with dose*1.7 as DFE. We found that there are too many multivitamin products or prenatal vitamins have a overdose folate according to its label which are a potential risk for the adults. The pregnant women need to aware of this important notice, please refer to 2017 Best Prenatal Vitamins for more detail introduction.