I got this e-mail today from Dr. Joel Fuhrman and I knew I had to share this information with you. I care about your wellbeing and I think you need to know this.
Women who take conventional prenatal vitamins or multivitamins may be endangering their health. A 9-year study in Sweden found that women who took multivitamins were actually more likely to be diagnosed with breast cancer. Why? My extensive research on this issue indicates it is the high dose of folic acid found in most multivitamins, and other researchers agree.1 I have been reviewing the studies implicating folic acid to heightened cancer risk for years and years ago felt it important to offer supplements without this risky ingredient, especially since real food folate is so easily obtained via green vegetables and beans.
Folic acid is the synthetic form of folate, one of the B vitamins. Folate is most known for preventing neural tube defects during early pregnancy, and is also important for immune function, cardiovascular health, and cancer prevention. Folate is abundant in green vegetables, but taking synthetic folic acid is not the same as getting natural folate from plant foods.
The body processes folate and folic acid differently. Real folate from food is protective, synthetic folate from supplements may be dangerous:
A study compared breast cancer mortality rates between women who took folic acid during their pregnancy and those that did not. Thirty years later those women who were given a hefty dose of folic acid during pregnancy were twice as likely to die from breast cancer.2
A 10-year study on women taking multivitamins concluded that those who took multivitamins containing folic acid increased their breast cancer risk by 20-30%.3
A study investigating both food folate and synthetic folic acid found that only supplemental folic acid increased breast cancer risk. In other studies, women with low levels of food folate intake were more likely to be diagnosed with breast cancer.4,5 Not enough natural folate and too much folic acid both increase risk.
Folic acid may disrupt the normal actions of natural folate, resulting in increased risk of several cancers, breast cancer included – and Americans are consuming more folic acid than ever before. Between conventional multivitamins and mandatory fortification of refined grain products (white rice, white flour, etc.), Americans are exposed to excessive amounts of folic acid on a daily basis. Many scientists have expressed concern that this excess folic acid poses serious risks of cancer to the population.6-9 Most people (including most physicians) are completely unaware that these issues and risks exist; and this ignorance can be dangerous.
1. Larsson SC, Akesson A, Bergkvist L, et al. Multivitamin use and breast cancer incidence in a prospective cohort of Swedish women. Am J Clin Nutr 2010;91:1268-1272.
2. Charles D, Ness AR, Campbell D, et al. Taking folate in pregnancy and risk of maternal breast cancer. BMJ 2004;329:1375-1376.
3. Stolzenberg-Solomon RZ, Chang SC, Leitzmann MF, et al. Folate intake, alcohol use, and postmenopausal breast cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr 2006;83:895-904.
4. Sellers TA, Kushi LH, Cerhan JR, et al. Dietary folate intake, alcohol, and risk of breast cancer in a prospective study of postmenopausal women. Epidemiology 2001;12:420-428.
5. Kim YI. Does a high folate intake increase the risk of b reast cancer? Nutr Rev 2006;64:468-475.
6. Smith AD, Kim YI, Refsum H. Is folic acid good for everyone? Am J Clin Nutr 2008;87:517-533.
7. Figueiredo JC, Grau MV, Haile RW, et al. Folic acid and risk of prostate cancer: results from a randomized clinical trial. J Natl Cancer Inst 2009;101:432-435.
8. Kim YI. Will mandatory folic acid fortification prevent or promote cancer? Am J Clin Nutr 2004;80:1123-1128.
9. Mason JB. Folate, cancer risk, and the Greek god, Proteus: a tale of two chameleons. Nutr Rev 2009;67:206-212.