Folic Acid Fortification Might Boost Cancer Risk

Nov. 18 -- TUESDAY, Nov. 17 (HealthDay News) -- Although folic acid fortification of foods can prevent many birth defects, it may also increase the risk for developing cancer, Norwegian researchers report.

Since 1998, many countries have mandated folic acid (vitamin B9) fortification of foods to decrease the incidence of neural-tube defects in newborns. By October 2009, the flour produced in these countries, plus the flour that is fortified voluntarily, represented 30 percent of the world's wheat flour produced in large mills. In addition, some 40 percent of those living in the United States also take dietary supplements containing folic acid, the researchers noted.

However, "Folic acid fortification and supplementation may not necessarily be as safe as previously assumed," said lead researcher Dr. Marta Ebbing, from the Department of Heart Disease at Haukeland University Hospital in Bergen. "Public health and food safety authorities should take this into consideration."

In Norway, foods are not supplemented with folic acid, making it the ideal place to investigate whether or not the supplement increases the risk for cancer, Ebbing noted.

"The study shows that treatment with folic acid for approximately three-and-a-half years was associated with a 21 percent increased risk of cancer and an increased risk of death after six-and-a-half years of follow-up in a large population of patients with ischemic heart disease living in Norway, where there is no folic acid fortification of foods," she said.

The report is published in the Nov. 18 issue of the Journal of the American Medical Association.

For the study, Ebbing's team collected data on 6,837 patients with heart disease from two trials. These trials were designed to see if vitamin B could lower homocysteine, a protein associated with an increased risk of heart disease.

In the studies, patients were randomly assigned to receive folic acid plus vitamins B12 and B6, folic acid plus B12, or B6 alone, or a placebo. These trials ran from 1998 to 2005, and were followed through the end of 2007.