Tuesday, October 23, 2012 9:41 AM Jim Swayze said: 

> Correlation doesn't equal causation.  I'm not sure whether I'm worried
about nitrates/nitrites.

[Ron] I agree whole-heartedly. Of at least equal importance is that we have
been exposed to many carcinogens for many millennia. We spent much more time
in the sun, arsenic was, to varying degrees, in our drinking water, asbestos
was present in the air, we burned wood and breathed the smoke, etc. Chemical
carcinogens were not as common, of course, but we have immune systems that
should, and probably did, quickly destroy cells with damaged DNA. However,
as was pointed out by Stanislas Tanchou in the 1840s, it is only in the
context of a "civilized diet" that we see significant cancer death rates.
The evidence suggests that there are several contributing reasons for the
steady growth of cancer death rates. Since Tahchou's time: 

1. We are certainly better at diagnosing a variety of cancers than we were
170 years ago.
2. Our consumption of cereal grains and dairy products, which contain
opioids, probably down-regulated our natural killer cell function which is
our fist line of defense against malignancy.
3. Our enormous increases in sugar consumption, led to predominantly high
blood glucose which is the only substance that provides energy for the
reproduction, growth, and spread of malignant tissues.
4. With increasing mechanization of farming, grains, dairy, and sugar are
much cheaper and are therefore constituting an increasing portion of our
diets.

Best Wishes, 
Ron