According to a study published in the Journal of the American Medical Association, Researchers have found that folic acid and other vitamin B supplements do not offer any benefit in lowering cancer risk. On the upside, researchers noted that it won’t increase your risk either.

Dr. Shumin Zhang, study author and an associate professor of medicine at Brigham and Women's Hospital and Harvard Medical School, in Boston said, "In women at risk of cardiovascular disease, we found that folic acid, vitamin B6 and vitamin B12 had no beneficial or harmful effects on the risk of invasive cancer or breast cancer."

A seven year study from April 1998 through July 2005 of 5442 women was undertaken who participated in the Women's Antioxidant and Folic Acid Cardiovascular Study. The women all over 42 years and had either preexisting cardiac disease or three or more risk factors for heart disease. They were randomly given 2.5 mg folic acid, 50 mg vitamin B-6 and 1 mg vitamin B-12 or placebos. Neither the women nor the doctors knew which woman was taking which supplement in what is called a "gold standard" for medical evidence.

During the study period 379 women developed invasive cancer of which 187 were in the active treatment group and 192 in the placebo group. Of the women who developed cancer, 154 developed breast cancer and 70 were in the active treatment group and 84 in the placebo group. The researchers however noted that there was a protective effect from the supplements in women over the age of 65 possibly as there need for the nutrition is higher.

The U.S. Centers for Disease Control and Prevention mandated folic acid being added to cereals and breads since January 1998 as it has been shown to prevent neural-tube defects, such as spina bifida. "There are really good reasons for women to take folic acid, especially if they're planning on having a baby, because there's really conclusive evidence that it can reduce birth defects. But, for the average woman in terms of cancer risk, folic acid and B vitamins don't seem to increase or reduce risk," Zhang said.

Michael Thun of the American Cancer Society who wasn't involved in the new study said, "It would be wonderful if taking a pill could reduce our risk of developing any kind of cancer. People are hoping for an easy solution, and that's difficult to find. The people who are most likely to take multivitamin supplements are the least likely to have a vitamin deficiency."

Victoria Stevens, strategic director of laboratory services for the American Cancer Society said, "Supplements aren't a magic bullet" for cancer prevention. There was a suggestion of a protective effect in older women that I think is worth following-up," Stevens added.