Good and Bad of folic acid

[Guest guest]

http://www.sciencedaily.com/releases/2009/04/090401134421.htm

For the past several decades, evidence has shown that greater dietary intake

of the B-vitamin, folate, offers protection against the development of

certain common cancers and reduces neural tube defects in newborns, opening

new avenues for public health interventions that have a great impact on

health.

However, folate’s central role as an essential factor in DNA synthesis also

means that abundant availability of the vitamin can enhance the development

of pre-cancerous and cancerous tumors.

Further, the intake of folic acid that results from consuming foods that are

voluntarily fortified (e.g.: ready-to-eat cereals) in combination with the

additional intake received from mandatory fortification of flour means that

supplementary intake of folic acid is unnecessary for many segments of the

population, and may even present a risk. Nevertheless, the issue is a

complicated one since women of child-bearing age seem to benefit from

supplemental folic acid in regard to its protection against birth defects.

In the April issue of the journal *Nutrition Reviews*, two new articles by

Dary, Ph.D., and B. Mason, M.D., assess the conditions under which

folic acid can be beneficial and harmful and contribute to guidelines for

the healthful intake of folic acid as a complement to dietary folate.

The consequences of inadequate folate intake remain prevalent in many

countries, even in industrial countries where specific interventions of

folic acid have not been implemented. Moreover, there continues to be some

concern—which, to date, lacks compelling scientific evidence—that the

synthetic form of the vitamin, folic acid, might have adverse effects that

do not exist with natural sources of folate.

Under most circumstances, adequate intake of folate appears to assume the

role of a protective agent against cancer, most notably colorectal cancer.

However, in select circumstances in which an individual who harbors a

pre-cancerous or cancerous tumor consumes too much folic acid, the

additional amounts of folate may instead facilitate the promotion of cancer.

In countries in which the fortification of flour with folic acid is working

well, additional supplementation in the form of vitamin pills can lead to

excessive intakes of the vitamin, which can then have undesirable adverse

effects.

Thus, folate appears to assume different guises depending on the

circumstances. The level of intake of this micronutrient that is safe for

one person may be potentially harmful to another.

“These effects of folate on the risk of developing cancer have created a

global dilemma in the efforts to institute nationwide folic acid

fortification programs around the world,” Mason notes.

Most individuals in the U.S. population are now folate-replete, so one

consideration would be to reduce the doses of the vitamin that are present

in most over-the-counter supplements. Many people receive sufficient amounts

of folate through their diet.

Now that the supply of folic acid in the diet is much larger than it was

prior to mandatory fortification, food policies may need to be adjusted to

the current knowledge and the new circumstances.

“The design of cogent public health policies that effectively optimize

health for many while presenting no or minimal risk to others, must often

occur in the absence of complete information,” Mason concludes. “However, we

are nevertheless obliged to deliberate with as much of an in-depth

understanding as the existing science allows.”

------------------------------

*Journal references*:

1. Mason et al. *Folate, cancer risk, and the Greek god, Proteus: a tale

of two chameleons*. *Nutrition Reviews*, 2009; 67 (4): 206 DOI:

10.1111/j.1753-4887.2009.00190.x<http://dx.doi.org/10.1111/j.1753-4887.2009.0019\

0.x>

2. Dary et al. *Nutritional interpretation of folic acid interventions*.

*Nutrition Reviews*, 2009; 67 (4): 235 DOI:

10.1111/j.1753-4887.2009.00193.x<http://dx.doi.org/10.1111/j.1753-4887.2009.0019\

3.x>

--

Ortiz, MS RD

A Healthy Body is a Terrible Thing to Waste

Save the earth. It's the only planet with chocolate