It seems that bacon, ham and sausages may be in the same category of carcinogens as cigarettes, alcohol and arsenic (class 1 carcinogens). So say the World Health Organisation, anyway. In fact, they've essentially concluded that red meat is carcinogenic to humans full stop (class 2a carcinogen).
That sounds bad, but they've also said that breathing air is a class 1 carcinogen, so it's difficult to know what exactly we're supposed to do with these conclusions. It's not as though all that many people are on a 40 sausage-a-day habit, so a direct comparison with smoking also seems a little unfair.
I'm reminded of an article Jeremy Paxman wrote a few years ago where he had been reading the National Dictionary of Biography, and observed that people don't just die in their sleep or of old age any more. You might be 199 years old, but when you die, we will be able to observe exactly what it was that finally pushed you over the edge.
These observations on what causes these cancers seems to me to fall into the same kind of category; processed meat may well cause cancer, but it's probably been killing us as a species for thousands of years and we've only now been able to determine exactly how.
This is all fairly timely for me. I had a scan the other day that revealed some abnormalities in my bowel that need to be removed. They're probably not cancerous, but over the course of the next ten years or so, they're reasonably likely to become cancerous, so they've got to come out. It's an amazing thing that we can find this out now and do something about it, but it's not very difficult to imagine how, in another time and place, this could easily have gone completely undetected and perhaps carried me off in my seventies. That's how people used to die, isn't it? At the end of it all, something has to kill you, after all.
When I was having the scan a few weeks ago, I was chatting to the guy supervising the process:
"So, what causes these abnormalities?"
"Well, we can't really say for certain, but it seems likely that they can be caused by eating processed meats like bacon and by drinking beer...." At this point, I think he must have seen the look on my face as my world was pulled out from under my feet and I contemplated a world without bacon and beer. "....but then again, teetotal vegetarians get them too, so who really knows?"
The MCU Project: Iron Man 
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