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Does folic acid cause breast cancer?

Does folic acid cause breast cancer?

Ask Dr. Kim . . .

Dr. Young-in Kim, a researcher and physician at St. Michael’s Hospital in Toronto, Canada,  has for the first time successfully proven that folic acid supplements–in dosages of 2.5 to five times the daily required dose—“significantly promotes” the development of existing carcinogenic or precancerous units in the mammary organs of rats.

breast cancer

Dr. Young-In Kim

Kim, whose research was just published in the online medical journal PLOS ONE, is also a professor of medicine at the University of Toronto, says these results clearly suggest that women who take large doses of folic acid can develop breast cancer.  Indeed, members of the medical community have more recently considered folic acid, a synthetic form of folate, a B vitamin, to be “highly controversial”.

The quantity of folic acid used in North America alone has significantly increased over the past decade and a half.  Pregnant women are routinely told to take folic acid in order to avoid such neural tube birth defects as spina bifida.   While some research once indicated it offered some protection against breast cancer, more recent research indicates that large amounts of folic acid can actually increase the risk of getting breast cancer.

Kim states: “This is a critically important issue because breast cancer patients and survivors in North America are exposed to high levels of folic acid through folic acid fortification in food and widespread use of vitamin supplements after a cancer diagnosis.  Cancer patients and survivors in North America have a high prevalence of multivitamin and supplement use, with breast cancer patients and survivors having the highest prevalence.”

Since 1998 both the US and Canadian governments have required manufacturers of food  to put folic acid into such items as enriched pasta, white flour and cornmeal products  to ensure that women do not suffer from a deficiency.   Research also reveals that at least 30 percent of North Americans take folic acid supplements in hope of obtaining unproven health benefits.

 (Image courtesy of St. Michael’s Hospital)

About Will Phoenix

W. Scott Phoenix, B.A., B.S. was born in Hawaii, raised in Pennsylvania and resides in California. He has been a published writer since 1978. His work has appeared (under various names) in numerous places in print and online including Examiner.com. He is a single parent of three children and has also worked as an actor, singer and teacher. He has been employed by such publications as the Daily Collegian and the Los Angeles Times.
  • Esnus

    In studies with HUMANS, unlike with this rat study, high dose supplements of folic acid notably decreased the risk of cancer (cited in the article “2 Big Lies: No Vitamin Benefits & Supplements Are Very Dangerous by Rolf Hefti”). Which evidence seems more relevant to you as a human being?

  • Will Phoenix

    Thanks for the comment, Esnus. I only have limited space but I did mention that they acknowledge there have been some studies that were pro-folic acid. There also seems to be some concern that we all take in more folic acid than we actually know. Again, I could only touch on so much and I honestly think the jury is out on the entire issue until we find out how much extra folic acid your average woman takes in outside of what is prescribed. Thanks for reading my stuff!