Folic Acid - The good and the bad...

Folic acid (Also known as folacin, folate, and vitamin B9) has a well-known benefit: if all childbearing women would take folic acid supplements, possibly up to 70 percent of neural tube defects would be prevented. However, many men and women take folic acid supplements to improve their health in general, and one would like to know whether there is any real benefit. Many studies involving other vitamins (C and E in particular, see our writeup for details) did not provide any indication of improved health resulting from their ingestion.

Some recent studies have addressed the issue of the impact of folic acid intake. An article in the British journal "The Lancet" (p 1876, v 369, 2007) presents results of a meta-study (combination of many previous studies) regarding the impact of folic acid intake, and stroke prevention. They found that for people taking folic acid supplements for more than 36 months, the risk of stroke was reduced by 29%, (13% to 43% Margin of Error). Since this is a combination of many trials involving different doses, there is no clear conclusion as to exactly how much folic acid should be taken. The authors state that their results are still not conclusive. Most of the reduction occurs in individuals who have not had a history of stroke.

Another study looked at the prevention of colon cancer by folic acid consumption (JAMA, p 2351, v 297, 2007). They find that folic acid did not decrease the risk colon cancer while taking up to 1 mg a day. Indeed, the opposite may be true! Folic acid was associated with a higher risk of having three or more adenomas (non cancerous tumors that could become cancerous) and non-colorectal cancers - the Risk Ratio was 1.67 (67% risk increase); however, the Margin of Error ranged from 1.00 to 2.80. Thus there is still a possibility that there is no risk increase.

Additional studies have addressed the issue of dementia prevention through folic acid intake. An article in The Lancet (v 369, p 208, 2007) presents results of a double-blind trial (half the participants get a pacebo) in which about 800 people (men and post-menopausal women aged 50 to 70) were tracked for three years. One group received 800 micrograms of folic acid a day, while the other half - a placebo. Participants were selected only if they had a high homocysteine level that is indicative of increased risk for vascular disease. The group that took the folic acid scored on a battery of cognitive tests as if they were several years younger than those who took the placebo. A different (double-blind) study (New England Journal of Medicine, V 254, p 2764, 2006) followed 276 participants, also with high homocysteine levels, over a two-year period. The treatment group took 1000 micrograms of folic acid, 500 micrograms of vitamin B12, and 10 miligrams of B6. They found no improvement in cognitive performance at the end of the study, in the group taking the vitamins!

If you benefitted from this site, please consider supporting us.