Can Antioxidants Really Kill Cancer Cells?

Cancer CellsAntioxidants have long been touted for their presumed ability to fight disease by preventing free radical induced damage to cells and DNA. This ability is beneficial because defects in DNA and DNA repair capabilities are thought to lead to numerous health disorders. In fact, there are currently hundreds of studies dedicated to determining the effects that antioxidants have on diseases such as heart disease, obesity, inflammation, multiple myeloma, Alzheimer’s disease and type-2 diabetes. One of the most recent studies examined the effects of antioxidants on cancer cells, and the results, which were both encouraging and yet surprising, were published in the Proceedings of the National Academy of Sciences, on March 19, 2012.

The Study


This study, which was conducted by researchers at the National Institute of Health (NIH), was designed to determine the exact effects that antioxidants have on cancer risk and cancer cells. The researchers at NIH used lab grown cells derived from human kidneys in order to examine the damaging effects of 4,000 different toxic chemicals on DNA and subsequently determine methods of DNA repair.

The screening results were surprising because the researchers identified 22 antioxidants that in high doses, actually damaged DNA and killed cells, as opposed to repairing and protecting them. This discovery challenges the long-held belief that antioxidants are beneficial to all types of disease. On the contrary, it suggests that certain antioxidants may do more harm than good to health disorders such as diabetes because high doses of these antioxidants may cause unexpected DNA damage that will ultimately lead to additional health problems. This discovery is both significant and problematic because of those identified (DNA damaging) antioxidants – genistein (contained in soybeans, chick peas, fava and other legumes) and baicalein (derived from the Baikal Skullcap plant) are currently being used to treat heart disease, osteoporosis, chronic hepatitis, type-2 diabetes and several other disorders.

On a positive note, the surprising ability of the 22 identified antioxidants to both support cells and DNA whilst also damaging them, may be very beneficial for the treatment of cancer and may even help to halt cancer development.

How These Antioxidants Could Possibly Kill Cancer Cells

Genistein is said that it could aid in halting cancer risk and cancer development by binding to tyrosine kinase, an enzyme that is linked to the growth of cancer cells. In addition, both genistein and baicalein have been found to inhibit cell proliferation and induce cancer cell death.


Therefore research is starting to show that certain antioxidants could possibly help to fight drug-resistant cells by first sensitizing them then inducing cell death. Furthermore, it is hypothesized that, when taken in combination with chemo, they can all help to reduce the side-effects and enhance the effectiveness of the chemotherapy.


While no studies have been done to support the antioxidant claims in humans, cell studies are showing promise. No definite conclusions with regards to the ability of antioxidants to kill cancer cells and reduce cancer risk can be drawn until further studies are conducted. Luckily, researchers are doing just that; there are over 43 studies currently underway, investigating the ability of antioxidants to treat prostate, pancreas, bladder, breast, kidney and skin cancer, amongst others.