—Supports Need for Additional Research—
WASHINGTON, D.C., June 5, 2007 — The Council for Responsible Nutrition (CRN) today responded to a study and accompanying editorial on folic acid and the prevention of cancer in the June 6 issue of the Journal of the American Medical Association (JAMA) by urging the scientific research community, the media, and the government not to jump to conclusions that would undo the important strides made in recent years in encouraging supplementation and food fortification with folic acid.
"The benefits of folic acid are well-documented, particularly in the area of reducing the risk of neural tube birth defects," said Andrew Shao, Ph.D., vice president, scientific and regulatory affairs, CRN. "There is also promising scientific evidence for folic acid in reducing the risk of congenital cardiovascular defects, stroke, and Alzheimer’s disease. It would be a huge public disservice potentially resulting in extremely negative health consequences if scientists, the media or government rushed to judgment based on this study."
CRN noted that the study, which found that folic acid did not prevent the incidence of benign tumors (colorectal adenomas) in patients with a history of tumors, was conducted in response to epidemiological studies showing a potential benefit. The lack of an observed benefit in this study may have resulted because folic acid was used like a drug to treat pre-existing disease, rather than as a nutrient. "It’s not surprising that folic acid alone may not prevent the recurrence of adenomas," said Dr. Shao. "Perhaps in combination with other related nutrients or in subjects without previous adenomas we would have seen more promising results, confirming what was suggested from earlier research."
In examining the secondary results of the study, which hinted at the possibility that an over abundance of folic acid might promote cancer cells in those who already have cancer, the editorial noted the "dual effect" that refers to other previous research on folic acid which found protection against development of cancer. Dr. Shao noted he supported the researchers’ call for further research to determine the validity and potential reasons behind their findings, but emphasized that the findings involved a relatively small number of diseased subjects, limiting the generalizability of the results to the generally healthy population. "Consumers can still feel they are doing something good by supplementing or fortifying with folic acid," he noted.
The trial used 1,000 micrograms (mcg) of folic acid per day which is the tolerable upper intake level (UL), but not the recommended intake. Most multivitamins contain between 200 and 400 mcg per serving, for consumption on a daily basis. Combined with food fortification, which is estimated to provide up to 120 mcg per day of folic acid, the American population is still consuming well below the UL for folic acid.
CRN noted the study authors indicated their findings were "equivocal" and that even the accompanying editorial stated "the question of folate in cancer prevention is not resolved."
"This study is an interesting addition to the current scientific literature, and more research should be done. In the meantime, consumers should not deprive themselves of the known benefits of folic acid."
CRN reminds anyone who has colon cancer (or any other cancer) or is at high risk for the disease, to consult a healthcare professional to determine the best course of action.