Anti-oxidants Elevate the Risk of Developing Cancer: Study

A new study shows that anti-oxidants increase the risk of developing cancer, knocking down previous claims that tie anti-oxidant supplements to reduced risk of certain cancers.

For decades, people worldwide have been taking anti-oxidant supplements in order to boost their well-being. It is believed that anti-oxidants lower the risk of cancer, but this has been pulled down by several clinical trials.  Most of the trails failed to highlight the protective effect of the anti-oxidants against cancer. A few trials clearly showed that anti-oxidants elevated the rate of certain cancers. Especially, smokers taking extra beta carotene had a higher, and not lower, rate of lung cancer.

In the latest study provided by the Cold Spring Harbor Laboratory, it has been explained as to why anti-oxidant supplements are not effective in lowering the risk of cancer development and why they harm instead of doing well.

They base their findings on the recent understanding of how the system in our cell that strikes a natural balance between oxidizing and anti-oxidizing compounds in the body.  They found that the compounds are involved in redox reactions (reducing and oxidation) that are crucial for cellular chemistry.

An oxidant hydrogen peroxide is needed in very less quantities and is manufactured within cells, large amount of oxidant can be a problem as it gets toxic. Cells present in the body naturally produce their own anti-oxidant to neutralize the toxic effect. This could be why people turn to anti-oxidants to counter the effects of toxic 'reactive oxygen species' ROS.

The researchers explain that there is no benefit of taking anti-oxidant supplements or consuming large quantities of food rich in anti-oxidants as they fail to act at the key site in the cell where tumor-generating ROS is produced. And, these supplements accumulated at scattered distant sites in the cell, by leaving the tumor-promoting ROS untouched.

"Therapies that raise the levels of oxidants in cells may be beneficial, whereas those that act as antioxidants may further stimulate the cancer cells. Interestingly, radiation therapy kills cancer cells by dramatically raising levels of oxidants. The same is true of chemotherapeutic drugs -- they kill tumor cells via oxidation," said David Tuveson, M.D. Ph.D., Cold Spring Harbor Laboratory Professor and Director of Research for the Lustgarten Foundation, and Navdeep S. Chandel, Ph.D., of the Feinberg School of Medicine at Northwestern University.

The finding was documented in The New England Journal of Medicine.