From the first moment my wife discovered
she had breast cancer, there was a deafening silence from the men I know. Even
ones whose wives, mothers or girlfriends had breast cancer seemed to have
received a gag order from some Central Cancer Command and did little more than
mumble about the experience. Not one to shut up for any known reason, I started
this blog…That was four years ago – as time passed, people searching for
answers stumbled across my blog and checked out what I had to say. The
following entry appeared in May of 2012 and is a continuation of this essay: http://breastcancerreaper.blogspot.com/2012/05/another-hold-on-there-baba-louie-moment.html
Doctors harp on
exercise.
Despite the
harping – or in my case, perversely because of it – I avoid exercise like the
plague.
Even so, as I
read more and more sites promoting the “exercise makes you better if you have
breast cancer” meme, I found that almost none of them give any kind of evidence
as to WHY exercise fights cancer and promotes healing.
So I dug into
the sites and finally found some evidence supporting this wild, “Do this one
weird thing…” kind of meme. This week, it’s number:
9) Physical activity appears to enhance
proliferation of lymphocytes, increases the number of natural killer cells and
increases lymphokine-activated killer cells activity.
What’s a
“lymphocyte”?
What’s a
“natural killer cell”?
What’s
“lymphokine-activated killer cell activity”?
To tell you the
truth, these appear to fade from easily definable to mumbo-jumbo-ish, so let’s
have at it!
But we need to
take one more step backward and start with White Blood Cells.
In contrast to
the RED blood cell, which are the cells that make up the visible part of the
blood. The red blood cells – or rbc’s – are the part of the blood that makes it
RED! It’s red because each of the rbc’s has many heme molecules in it. The heme
molecules are the ones that carry a tiny iron atom in their center. It’s the
iron atom that OXYGEN grabs hold of so that the rbc’s can carry oxygen to the
lungs allowing us to BREATHE. There are zillions of these little suckers in
your bloodstream at all times and THEY come from the marrow in your bones.
So white blood
cells – or wbc’s – don’t have heme in them; therefore they are, by comparison,
WHITE. But they still travel in the bloodstream. Instead of carrying oxygen,
they attack and destroy any germs that get into your body. They also take care
of any other junk that gets in.
Lymphocytes are
a kind of wbc. There are three kinds of lymphocytes – natural killer cells, T
cells and B cells. Another name for the natural killer cells are NK cells. T
cells are the kind of cells that the Human Immunodeficiency Virus (HIV)
targets.
NK cells have
the specific duty of protecting the body from tumors and viruses by “popping”
the cells to destroy them; the other two handle the release of cytokines, lysis
and immune regulation and creating antibodies.
The effect of
exercise on NK cells however, seems to be blasted out of the water by the study
referenced below and quote here: “…latent CMV infection is associated with
lowered numbers of NK-cells expressing inhibitory receptors and a blunted
mobilization of NK-cells in response to acute exercise. This may indicate a
compromised immune response to ‘fight-or-flight’ situations in those infected
with CMV.”
Conversely,
“Moderate exercise has been reported to produce an anti-inflammatory
environment and thus reduce the risk of infection. Conversely, continuous,
intense exercise may increase oxidative stress (an overproduction of reactive
oxygen species compared to the body’s ability to detoxify), inflammatory
responses, as well as the risk for infection.”
And blasting
back from the other side: “Longitudinal training studies in previously
sedentary people have failed to show marked changes in T and B cell functions
provided that blood samples were taken at least 24 h after the last exercise
bout.” Also: “Evidence suggests that the prophylactic effect of exercise may,
to some extent, be ascribed to the anti-inflammatory effect of regular exercise
mediated via a reduction in visceral fat mass and/or by induction of an
anti-inflammatory environment with each bout of exercise (e.g. via increases in
circulating anti-inflammatory cytokines including interleukin (IL)-1 receptor
antagonist and IL-10). To understand the mechanism(s) of the protective,
anti-inflammatory effect of exercise fully, we need to focus on the nature of
exercise that is most efficient at allieviating the effects of chronic
inflammation in disease. The beneficial effects of endurance exercise are well
known; however, the antiinflammatory role of strength training exercises are
poorly defined. In addition, the independent contribution of an
exercise-induced reduction in visceral fat versus other exercise-induced
anti-inflammatory mechanisms needs to be understood better. There is consensus
that exercise training protects against some types of cancers. Training also
enhances aspects of anti-tumour immunity and reduces inflammatory mediators.
However, the evidence linking immunological and inflammatory mechanisms,
physical activity, and cancer risk reduction remains tentative.”
Translated: “We
don’t know enough yet to say if exercise is magic”.
I’m NOT saying
exercise is a waste of time. There are enough other benefits listed above to
induce anyone who is hesitant or ridicules the IMPORTANCE of exercise in
fighting and recovering from cancer (in this case breast cancer specifically)
to start a regimen of moderate exercise and make it a regular part of life.
BUT if anyone
says that the data are in and it’s a win and then runs out to hire a trainer or
join an exclusive club offering personal coaching and cutting edge
vegetable-fruit mixed drinks…well, like everything else that has to do with
breast cancer, there’s no “cure all”, no magic bullet and nothing that works
for everyone all the time.
Resources: http://en.wikipedia.org/wiki/Lymphocyte,
http://www.ncbi.nlm.nih.gov/pubmed/21933704,
http://www.nsca-lift.org/HotTopic/download/Immune-Function.pdf,
http://www.ncbi.nlm.nih.gov/pubmed/21446352
