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Taking dietary supplements full of antioxidants could help cancerous tumors grow

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31–40 of 69 posts

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#33
post #5

Does this mean that people undergoing chemo shouldn't have any supplements at all? Lutein, for example, is a strong antioxidant but also has anti-cancer properties. Edit: thanks for the replies!

Should not take high doses of antioxidants to be more specific.

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#34
post #18
post #3

> this discovery surprised researchers No it didn't, not to anyone paying attention https://www.science.org/content/blog-post/n-acetyl-cysteine-... https://www.science.org/content/blog-post/exercise-and-vitam... https://www.science.org/content/blog-post/antioxidants-and-c... https://www.science.org/content/blog-post/evidence-piles-ant...

Exactly, it’s been well known for a while. There was a paper comparing physical fitness between two groups - one got high dose vitamin C, one didn’t. The ones take high dose vitamin C saw a far worse improvement in physical fitness. Why? Metabolism generates free radicals. The body used that as a signal to drive the changes that result in improved physical fitness. It’s one of those things where a given molecule has…

http://www.pnas.org/content/early/2009/05/11/0903485106.shor...

It is worth noting the sample size, the focus on insulin sensitivity on healthy males, and lack of consideration of other beneficial antioxidant health outcomes.

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#35

Recommended reading on this includes "Do You Believe in Magic" by Dr. Paul Offit, the Director of the Vaccine Education Center and professor of pediatrics at Children's Hospital of Philadelphia (certainly one of the best children's hospitals in the world).

Interesting, picked up a used copy. Thanks for the recommendation!

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#36
post #7

> Common antioxidants, such as vitamins A, C, selenium, and zinc, can stimulate the growth of blood vessels in cancer when taken in excess. Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. The second part is because we are continuously getting cancerous cells, but for the most part our immune system can deal with them before they become a problem.

> Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. Aren't we all and always in some state of "having cancer"? It's just a crappy modification away.

I would agree. I would phrase it differently, as "cancer" is a human defined term. Our bodies are constantly fighting abnormal cell growth.

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#37
Note by definition antioxidants are chemically reactive substances that want to react with ROS but may also want to react with other things.

Your body uses oxidation to do important tasks. For instance one way immune system cells destroy invaders and cancer cells is by oxidizing then to death.

To second order your body has antioxidant systems that try to maintain the right level of activity. N-Acetyl Cysteine affects the metabolism of

https://en.wikipedia.org/wiki/Glutathione

for instance and what your body does with it in the liver. Your body should try to maintain the right level of antioxidant activity as much as it can if you are consuming more or less vitamins.

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#38
post #7

> Common antioxidants, such as vitamins A, C, selenium, and zinc, can stimulate the growth of blood vessels in cancer when taken in excess. Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. The second part is because we are continuously getting cancerous cells, but for the most part our immune system can deal with them before they become a problem.

The paper says nothing about promoting the possibility of getting cancer. Only after the cancer is advanced enough that the cancerous cells have formed a tumor, according to this study the antioxidants promote the growth of the blood vessels of the tumor, which is very undesirable, because the better vascularized a tumor is, the faster it grows. When there is no cancer, promoting the growth of the blood vessels is a…

You might have cancer at a subclinical level years before you get symptoms. Some cancers (e.g. some prostate cancers) grow very slowly and might not kill you before something else does, in a case like accelerating cancer growth could make all the difference between something subclinical and something really dangerous.

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#39
post #7

> Common antioxidants, such as vitamins A, C, selenium, and zinc, can stimulate the growth of blood vessels in cancer when taken in excess. Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. The second part is because we are continuously getting cancerous cells, but for the most part our immune system can deal with them before they become a problem.

Vitamin C is hailed for contributing to immune system defense. So maybe having the right amount is best?

Re: Taking dietary supplements full of antioxidants could help cancerous tumors grow

#40
post #7

> Common antioxidants, such as vitamins A, C, selenium, and zinc, can stimulate the growth of blood vessels in cancer when taken in excess. Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. The second part is because we are continuously getting cancerous cells, but for the most part our immune system can deal with them before they become a problem.

> Is this to say that once you have cancer, these are bad, or that they promote the possibility of getting cancer. Aren't we all and always in some state of "having cancer"? It's just a crappy modification away.

I figured as much as well. We probably have few cancer cells popping up and eaten out every days or hours, and it only gets bad once whacks gets outpaced by moles or something.
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