Could antioxidants negate the effects of radiation therapy?

[Realitycheck]

Well, I already answered my own question, but I'm having a hard time editing my subject title.

 

The way that I understand it is this. Our cells undergo DNA damage all day, every day for whatever reason, but mostly damaged by free radicals. Antioxidants work "by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves."

 

On Wikipedia, the mechanism by which damage is done via radiation is unclear.

 

Radiation therapy works by damaging the DNA of cells. The damage is caused by a photon, electron, proton, neutron, or ion beam directly or indirectly ionizing the atoms which make up the DNA chain. Indirect ionization happens as a result of the ionization of water, forming free radicals, notably hydroxyl radicals, which then damage the DNA. In the most common forms of radiation therapy, most of the radiation effect is through free radicals.

 

Basically, what they are trying to say is that the radiation beam ionizes the water in the cell, which then forms hydroxyl radicals, which then damages the DNA, right?

 

So what I am wondering is this. Antioxidant therapy heals a lot more than just cancer cells waiting to happen. I know this from experience, as I have been supplementing with about 30 of them for the past month in a mad dash to get as healthy as possible before I start radiation therapy, and it works. I can tell most assuredly from my overall well-being. I have read that too much of them can be a bad thing, but I think that I have been taking a modest amount of many different kinds, 2 different formulas, but I digress.

 

I have read in one study that high doses of antioxidants can help alleviate some of the side effects of radiation therapy. I have read in another study that taking high doses of antioxidants during radiation therapy could negate the effects of the radiation therapy on the cancer cells. My doctor has advised me not to take any during radiation, though technically it was his nurse and I should ask him directly. What do you think about supplementing with a small, normal dose to help off-set side effects since " cancer cells generally are undifferentiated and stem cell-like, they reproduce more, and have a diminished ability to repair sub-lethal damage compared to most healthy differentiated cells.

 

Because cells have mechanisms for repairing DNA damage, breaking the DNA on both strands proves to be the most significant technique in modifying cell characteristics. Because cancer cells generally are undifferentiated and stem cell-like, they reproduce more, and have a diminished ability to repair sub-lethal damage compared to most healthy differentiated cells. The DNA damage is inherited through cell division, accumulating damage to the cancer cells, causing them to die or reproduce more slowly.

 

 

http://en.wikipedia.org/wiki/Radiation_therapy

http://en.wikipedia.org/wiki/Antioxidant

http://jama.ama-assn.org/cgi/content/abstract/297/8/842

http://altweb.jhsph.edu/wc6/paper535.pdf (study from Iran, of all places)

http://www.mdanderson.org/departments/cimer/display.cfm?id=C13957F3-148C-11D5-811000508B603A14&method=displayFull&pn=6EB86A59-EBD9-11D4-810100508B603A14

http://www.mdanderson.org/departments/nutrition/display.cfm?id=0B726B03-F6DA-11D4-810400508B603A14&method=displayFull&pn=0B726D07-F6DA-11D4-810400508B603A14

Edited October 19, 2008 by agentchange

[Mr Skeptic]

My guess is that taking antioxidants during radiation therapy will reduce the effect of the radiation wherever there is good blood flow. Now I know cancer cells often form extra blood vessels to them, and also that they don't get enough blood. But I don't know whether that is because they don't have enough blood vessels or because they require more blood. In the first case, the antioxidants would help the healthy cells more than the cancerous ones, but in the second case it could be the other way around. In either case, you might need a slightly higher dose of radiation to have the same effect, so you really should tell your doctor.

 

Oh, and how much do antioxidant pills cost?

[Realitycheck]

Vitamin Shoppe has a formula called Solgar Antioxidant Free Radical Formula which has 20 or 30 different types. Taking 2 per day, you get a month supply for about $25. They also have a generic called SuperAntioxidant which I was taking to cover all the bases. I read this one article which advised to include the following types. There are plenty of others that are proven to be effective and getting a wide range of them in your diet is also advised.

 

proanthocyanidins (grape seed extract)

glutathione (or n acetyl cystein, NAC)

polyphenols

Vit. E

carotenoids