Obesity 'leading driver' of breast cancerObesity is the biggest driving force behind the most common form of breast cancer in older women, say researchers.
Alcohol and then cigarettes are the next largest culprits, according to Cancer Research UK.
This is arrant nonsense for several reasons, as I said in my e-mail to the Beeb (see here for the details). In summary, there is not a scientist in the galaxy who believes that obesity and drinking are the main "drivers" of breast cancer and only a handful of certifiable anti-smoking maniacs like Stanton Glantz believe that smoking is a risk factor for breast cancer AT ALL.
The BBC's reply:
Dear Chris
Many thanks for getting in touch and raising your concerns.
You are correct that it is important to stress that the findings mean that obesity affects the levels of sex hormones. The article does this. We were mindful of this and discussed this point and the wording with cancer research uk before publication of the article. We explain that it applies only to hormone sensitive breast cancer in postmenopausal women and that the link suggests obesity drives up hormone levels.
Thanks again for contacting us. We value your feedback.
Kind regards
Since this ignores every point I raised in my earlier e-mail, I replied:
Sir/Madam,
I don't take issue with the bulk of the story in question, which reflects the study accurately in some respects. The main problem is the headline and the first two paragraphs, ie:
Obesity 'leading driver' of breast cancer
Obesity is the biggest driving force behind the most common form of breast cancer in older women, say researchers.
Alcohol and then cigarettes are the next largest culprits, according to Cancer Research UK.
Every word of this is demonstrably untrue. It is not a matter of interpretation or wording. Obesity is NOT the biggest driver of breast cancer - as with all cancers, age is the biggest driving force. Between the age of 29 and 69, a woman's odds of developing breast cancer increases from 1 in 2000 to 1 in 13. As Cancer Research UK's website says: "The strongest risk factor for breast cancer (after gender) is age"
After that, there is reproductive history. Childless women have twice the risk as women with large families (who breast-fed).
Family history of the disease also doubled the risk.
These are the true driving forces of breast cancer. Way down the list is overweight and obesity, with a 10-30% increase in breast cancer risk. Again, from CRUK: "Compared to lean (BMI 22.5-24.9) women, overweight post-menopausal women have a 10-20% increased risk of breast cancer, and obese post-menopausal women a 30% increase in risk."
Alcohol is also a risk factor, varying on consumption, but generally is considered to form a 10-50% increase in risk. (eg. http://aje.oxfordjournals.org/content/165/6/667).
Smoking is not generally considered a risk for breast cancer AT ALL, despite efforts by the BBC and the Daily Mail to tell the public otherwise. To claim that it is the third biggest driver of the disease is ignorant and inexcusable.
Sex hormones are undoubtedly a risk factor, and a major one. The study you reported on shows that obesity is a risk factor for higher sex hormones and that drinking and smoking may be "moderate" risk factors for higher sex hormones. The crucial points - which I hoped I explained in the previous e-mail, but perhaps not - is that (a) the authors of the study NEVER claimed that obesity, drinking and smoking are the main risk factors for higher sex hormones, let alone breast cancer, and (b) even if these 3 factors were the main risk factors for higher sex hormones, it does not follow that they are the main risk factors - or the 'leading drivers' - for breast cancer itself. Indeed, we know with as much certainty as is possible to have in science that they are NOT.
Your article did not "stress" that obesity affects sex hormones. On the contrary, it stressed, quite wrongly, in the headline and opening sentences that obesity is "the biggest driving force behind the most common form of breast cancer in older women". This is untrue. It then stressed that drinking and smoking were the next biggest drivers of breast cancer. This is untrue. You say that: "This latest work, published in the British Journal of Cancer, suggests obesity should go at the top of this list [of risk factors for breast cancer]". This is untrue. The author of the study said, in the press release you were doubtless sent:
“Our study shows that changes in hormone levels might explain the association of established risk factors such as obesity with breast cancer risk. Other studies have found that weight and alcohol can affect hormone levels and this research confirms and adds to these findings and provides more information about how breast cancer develops.”
Nothing in the CRUK press release or the study itself in any way supports the premise of your article. Are you prepared to stand by your claim that obesity, drinking and smoking are the "biggest driving forces" for breast cancer? If not, the article should be changed. It is too late to avoid misleading the bulk of its readers, but it would at least be an acknowledgement that the BBC knows when it has made a mistake.
Regards,
Chris Snowdon
Their reply...
Thank you for your comments, which have been noted.
BBC News website
Translation: 'Piss off and leave us to report Cancer Research UK press releases in anyway we see fit.' Needless to say, the article in question remains unchanged, so any woman who has recently been diagnosed with breast cancer can read it and blame herself for the disease.
I should say that my interest in pursuing this—as I will continue to do—is not because it is the worst example of BBC reporting I have ever seen. Far from it. It is because it is an open and shut case. Their reporting of this particular story is wrong in essence and in fact. To publish such garbage in the first place is lamentable, if forgivable, but to stand by it is appalling.
8 comments:
Good for you Chris and I admire your tenacity, but the BBC as you know are a law unto themselves. Good luck.
Good luck, keep plugging away.
Question - is it worth even bothering with the Beeb?
@james
I think that the answer is yes. The BBC is one of the most influential news providers on earth and is supposed to at least attempt to be impartial.
The issue with BBC health reporting is that the corporation does not employ anyone who has a clue, believes that the WHO and other politicised QUANGOS are still the idealistic organisations that they set out to be and implicitly trusts its favoured public health sources in the face of massive evidence suggesting that they should not. The BBC seems incapable of understanding that campaigning charities and the public health industry are vested interests.
I believe that their bias is to a large extent unintentional so Chris pursuing them in this way might at least achieve a bit of a rethink on their relationship with charity “experts”. The problem with this piece is that it was spun by CRUK and then spun again by the BBC so bears no resemblance to reality by the time the majority of the public gets to read it.
It would be nice if the BBC covered public health properly or not at all. What they produce at present is really unacceptable and below the standards that we should expect.
Great, Chris. Good work. I think you should carry on - and in a short while you will have enough material to fill a book about the BBC news and its (negative) association with the truth.
It would be a best seller, you know ;)
Chris, great work (and Ivan, great comment).
Since this overlaps several topics I have worked on over the years and write about, I wish I could offer some additional insight. But I have nothing -- you nailed it. I will pay the highest complement: This example is so perfect that I wish I had discovered and written about it myself.
Perhaps the only thing I might offer as insight is a little "causal pathways" thinking. If drink causes hormones and hormones cause cancer, but we already knew the that hormones cause cancer and drink causes cancer (a bit) then the new discovery is not that drink causes cancer but that the drink and the hormones are causing the same cases (they are steps on the same pathway). The study cannot possibly change our assessment about the independent risk of anything, but merely tell us about what sits on what pathway. (The same always applies to family history too -- it is always just a proxy for the real cause.) I know that you almost said this, so clearly get it, but this might help point it.
Good luck badgering them more!
Well done Chris. I lost my lovely mum to breast cancer. It was such a tough time for her and the family when she was diagnosed. She, like a lot of women, worried about her weight and always thought she was a little fat when she clearly wasn't. I hate to think what reading that article would have done to her, how bad it may have made her feel to think it was own her fault. Serious illness is of course terribly traumatic for everyone involved and can leave the victims very vulnerable. It's sickening that these reporters are willfully disseminating lies that mislead and add to the agony the victims are already experiencing. I don't know if they are just dumb or if they consider the trauma they cause others to be a price worth paying to achieve their puritanical objectives.
I wonder whether cancer is such a politically privileged disease that discussion of it is exempt from fuddy-duddy customs such as trying to get your facts right.
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