Good Grief, is anything safe?!?
https://www.washingtonpost.com/news/to-your-health/wp/2015/10/14/antioxidants-may-give-a-boost-to-cancer-cells-making-them-spread-faster-study-suggests/
Since the term "antioxidants" made the leap from the realm of
biochemistry labs and into the public consciousness in the 1990s,
Americans have come to believe that more is better when it comes to
consuming the substance that comes in things like acai berries, green
tea and leafy veggies.
A provocative new study published Wednesday in the journal Nature raises important questions about that assumption.
Antioxidants
— which include vitamins C and E and beta-carotene, and are contained
in thousands of foods — are thought to protect cells from damage by
acting as defenders against something called "free radicals" which the
body produces as a part of metabolism or that can enter through the
environment.
That's all great for normal cells. But what
researchers at the University of Texas Southwestern Medical Center found
is that antioxidants can work their magic on cancerous cells, too —
turbo-charging the process by which they grow and spread.
Researcher
Sean Morrison and his colleagues conducted experiments on mice that had
been transplanted with skin cancer cells (melanoma) from human
patients. They gave nothing to one group. To the other they gave doses
of N-acetylcysteine (NAC) which is a common antioxidant that's used
in nutritional and bodybuilding supplements and has been used as a
treatment for patients with HIV/AIDS and in some children with certain
genetic disorders.
The results were alarming: Those in the
second group had markedly higher levels of cancer cells in their blood,
grew more tumors and the tumors were larger and more widespread than in
the first.
"What we're starting to learn is that there can be bad
cells from cancer that appear to benefit more from antioxidants than
normal cells," he said in an interview.
Morrison, director of the Children’s Medical Center Research
Institute at UT Southwestern, explained that it has to do with something
called oxidative stress.
Scientists have known for a while now
that cancer metastasis — especially when it involves spreading a great
distance to another part of the body — is a very inefficient process and
that many cells die along the way. This is likely due to oxidative
stress, which is an inability by the body to counteract the harmful
effect of free radicals. When antioxidants supplements are given, the
paper hypothesizes, they may give new life to those cancerous cells that
are on the edge of dying.
Morrison said that previous studies have shown that the progression
of metastasis of human melanoma cells in mice is predictive of their
metastasis in humans, which raises concerns about the use of dietary
antioxidants by patients with cancer.
Moreover, melanoma may not be the only type of cancer to be affected this way.
A similar study conducted at Vanderbilt University and published in PLoS One in
2012 involving mice with prostate cancer also showed that antioxidants
appeared to increase the proliferation of cells in the pre-cancerous
lesions. And another one in rodents with lung cancer published in
Science Translational Medicine in 2014 found that normal doses of
vitamin E and smaller doses of acetylcysteine, an antioxidant
supplement, appeared to lead to a three-fold increase in the number of
tumors and caused them to be more aggressive. As a result, the mice
given antioxidants died twice as fast the ones in the control group. The
reaction appeared be dose dependent with larger doses leading to a more
severe reaction.
Morrison said that further study needs to be
done to confirm the findings and that cancer patients should still
consume antioxidants as part of a healthy diet.
But, he added,
"personally, from the results we've seen, I would avoid supplementing my
diet with large amounts of antioxidants if I had cancer."
Over
the past 20 years, numerous studies were launched to ascertain the
effect of antioxidants on other conditions ranging from heart disease to
memory loss. Early results have mostly been mixed, but that hasn't
stopped food companies from hyping their disease-fighting abilities.
I was diagnosed with thyroid cancer in Nov., 1999. Surgery and radioactive iodine followed. In Dec., 2006, I found a lump in my neck that turned cancerous. Shortly thereafter, it was found to have metastasized throughout my body and to be untreatable and inoperable. I started a clinical trial with Sutent (sunitinib) since Apr., 2007. In Nov., 2013, the tumors began growing again and I was removed from the Sutent Clinical Trial. I started a clinical trial taking of CEDIRANIB on 04/09/14.
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