For a long time, research has indicated that antioxidants
are extremely beneficial, especially in lowering the risk of cancer. Scientists have long thought that
antioxidants neutralize cell-damaging free radicals, lowering this risk. However, a new study shows that in mice,
rather than preventing and slowing down certain cancers, it had increased the
spread of malignant tumors, commonly in the lungs and in skin cancer.
High levels of antioxidants can result in protecting cancer
cells as well as normal cells. This
mechanism works by the tumor cells storing any excess amount of antioxidants
that are supplemented, allowing them to survive a greater amount of damage.
This often leads to a higher rate of metastasis due to an improved ability
caused by antioxidants to move and invade nearby membranes. In these metastatic
tumors, a higher amount of glutathione, an antioxidant made by the body, was
found. Glutathione also impacts RhoA, which
plays a role in moving cells to different parts of the body. These supplements also cause tumor cells to
turn off cancer-suppressing gene p53, which also results in metastasis.
Though these increased levels of antioxidants can progress
cancer at a faster rate, it may not necessarily trigger cancer. However, these findings can also bring
potential benefits by using this knowledge as a tool to target cancer. Cancers that are sensitive to the effects of
free radicals may be more susceptible to drugs that prevent them from producing
antioxidants, which could possibly be used one day as a treatment in these
types of cancers.
Link to article: http://www.scientificamerican.com/article/antioxidants-may-make-cancer-worse/
Antioxidants may not always be healthy! I came across several articles that have demonstrated through scientific studies that alarmingly, antioxidants can often act as prooxidants at high concentrations. In addition, it has been shown that the reactive oxygen species (ROS) that antioxidants target are actually necessary for normal cell signalling and gene regulation. It is important to realize that the redox reactions occurring in the body must be balanced and "too much of a good thing" can exist when it comes to exogenous antioxidant consumption.
ReplyDeleteCheck out the full articles for more detail:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2952083/
and
http://www.hsph.harvard.edu/nutritionsource/antioxidants/
We live in an era of great medicalization, especially when it comes to patterns of cancer and diet. Everything seemingly "causes" cancer these days and more and more foods, like ones that contain antioxidants, have been marketed to consumers to help prevent cancer. This issue of selectivity has always been the problem with cancer. How to we rid the bad and keep the good? It is interesting that these "free radical scavengers" are also agonists for p53, especially because p53 can up regulate genes with antioxidant products. I think your suggestion could apply to a cancers like lung and skin cancer!
ReplyDelete