Spotlight on Folic Acid

Found in leafy green vegetables, folic acid helps produce the genetic material in cells and is required by all cells that need to multiply rapidly. It's particularly important for making new red blood cells, cells that line the gastrointestinal tract, and for cell formation during fetal growth. Folic acid can reduce the risk of having a baby with certain defects of the spine and brain, and is important for heart health. Emerging science suggests that this essential B-vitamin might play an even greater role in keeping us healthy.

Beyond NTD?
Women who consume enough folic acid can reduce their risk of giving birth to babies with neural tube defects (NTD), such as spina bifida. Taking supplemental folic acid before and in the early weeks and months of pregnancy is crucial, since the neural tube forms during that period. Randomized trials and other studies show that if all women who could become pregnant were to take supplemental folic acid, the risk of NTD could be reduced by up to 75%. Preliminary evidence is now linking folic acid intake with lower risk of other birth defects such as cleft lip and palate, and some congenital heart defects. More research is needed to see whether increasing folic acid intake can truly impact the rate of malformations other than NTD.

Healthier Colon?
A growing body of evidence suggests that consuming enough dietary folic acid might also be able to help stave off colon cancer, the second leading cancer killer in this country. In the Nurses' Health Study, long-term intake of folic acid greater than 400 micrograms daily was found to substantially reduce the risk of colon cancer. And in a study from Tufts University, researchers found that people with pre-cancerous colon polyps had 34% less folic acid in their colon walls than people whose polyps were benign. Several trials are now underway to see whether increasing folic acid can actually help keep colon cancer at bay.

Heart Disease and More?
Finally, folic acid may help ward off heart disease by reducing levels of a naturally occurring compound in the blood called homocysteine. When levels of this compound build up, it is thought to damage the lining of arteries and promote blood clots. Population studies have shown that too much homocysteine in blood is related to a higher risk of coronary heart disease, stroke and vascular disease. folic acid, along with vitamins B6 and B12, has been shown to help reduce homocysteine when it is elevated. Research has also uncovered a link between high homocysteine, lower levels of these B vitamins, and age-related decline in mental function. We will have to stay tuned to research developments to know whether getting more of the Bs will truly help us stay mentally sharper and healthier as we age.

How can supplements help?
Multinutrient supplements can help us achieve better intakes of this important nutrient. Studies suggest that a sizeable portion of Americans consume far less folic acid than recommended, even though some foods are now folic acid-fortified. And the body more easily absorbs the form of folic acid in supplements than the natural form found in foods like green leafy vegetables. Several studies have shown that supplemental folic acid raises blood levels higher than equal amounts consumed in foods. So get the "B" attitude and eat a diet rich in natural and fortified foods, along with taking a multinutrient daily.

References

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