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Steak and Cancer

As the closing comment in the end of the month number for October suggests, there is an activist campaign against meat eaters.
In today's Daily Mail we are told that eating just one steak a week increases the risk of bowel cancer.
The risk increases by 2/5ths according to "a major study".
"Scientists" (I have taken to almost always including the quotes these days where i want to suggest that they are less scientist than they are activists and because the media isn't that scrupulous about defining what a scientists is nor in discriminating between a botanist commenting on nuclear physics and an English Lit graduate writing the government;s climate change legislation) claim a 42% higher risk when eating more than four portions of red meat.
The study was based 0on a sample of 500,000... (?)

But off (vegie) message, the study also claims that eating large amounts of fibre found in fruit and veg doesn't actually do much good despite the NHS advising us to get our five a day.

Now pardon me, but if those who eat loads of fruit and veg are just as likely to suffer bowel cancer as those who swallow a steak each week, then what on earth do the people who eat neither actually eating that are at far less risk of developing bowel cancer.

And of course, the eat five a day fruit and veg message was based on just such dodgy research, and is now claimed not to be true, so why should we believe this study any more?
I note in the same issue that a glass of wine a day now will affect your looks. Perhaps they think this will frighten women more than the risk of a nasty painful death.

But fear not, at the tail end of the article it declares that steak eaters are 18% more likely to develop bowel cancer than vegetarians - which actually presumably means that vegetarians are 24% more likely to develop bowel cancer than whoever it is that is eating whatever it is that means they are least likely to get bowel cancer.

I wonder what this study isn't telling us? That those least at risk of bowel cancer are smokers? (partly because they are wiped out by virulent cancers of every other sort before bowel cancer can get a look in, or perhaps because while more susceptible to some cancers they are also less susceptible to other types of cancer?).

And, oh dear, while they asked how often people eat red meat they failed to ask how much they ate and thus made an assumption based on average portion sizes. Average by whose standards? Food manufacturers seem to suggest rather modest portion sizes when advertising a package as being suitable for four portions which are then consumed by just two adults who still feel hungry.

But having forgotten to ask this important question, it would be a shame to have to go back to all 500,000 and ask them. Then too is there a bias in the response? How many people eat rather more or less than they remember?
Asking the public what they have been eating all their lives is always going to be a it suspect and especially as eating red meat has some sort of status value.

Frankly I'd be more concerned to know how much of this meat is imported and how much, for example, is horse meat from Europe or hormone fed meat from the US.... or maybe some report pet food as red meat? We hear such stories about older people.....

Re: Steak and Cancer

On the issue of scientists being activists or campaigners, I think you can take that as being pretty much a fact in the specific case of public health researchers, following a comment by Richard Horton , editor of "The Lancent", recorded in a blog on the Royal Society's website in 2013:


"Should there be a separation between scientists and campaigners? Is such a separation possible? Richard Horton pointed out that for a public health researcher, not being an activist is the exception."

It would probably help if the mainstream news media treated public health researchers as being just another lobby group and didn't give them the respect that they currently do.