Causes of Cancer

Attack

So after I attacked Vyvyan Howard, he has responded.

He has written a letter in the Guardian.

Adam Wishart's attack on us (Response, March 30) over environmental influences in cancer is political rather than scientific, in that he does not address any specific scientific issue we raised. Wishart is a graduate in politics and philosophy, so maybe it is not surprising that he doesn't wish to engage on the latest science concerning cell signalling disruption by xenochemicals.

The part of the letter that I find most interesting is

We wrote our paper as a scientific article. It underwent peer review and was published in a respected academic journal. It is doubtful that Mr Wishart's book will undergo such rigorous scrutiny.

Its interesting, parts of my book have been reviewed by more than a dozen senior scientists. Karol Sikora one of the most senior cancer scientists in the UK, and an advisor to the WHO, read it and said that it was accurate.

And yet Howard's article was written in the Journal of Nutritional and Environmental Health. Its a journal that does not even win a place in Pubmed. According to this website it seems that the journal hasn't published for a year. Howard's article was published online - and not as part of the normal publishing process.

Moreover, the journal is doubtless respected but within a quite small group of scientists. The editorial board includes many members of the alternative health community. And its most senior editor is Damien Downing who runs a company promoting nutritional responses to health.

I'm not saying that my book should be given more credence. I'm only saying that Howard is making a political as well as a scientific point. He should at least acknoweldge that.

Parents, don't fall for this pesticide/cancer scare story

The Guardian have kindly published a piece by me in their repsonse page.

The myth that pesticide residues are causing a rise in cancers has once again surfaced (Scientists warn parents on pesticides and plastics, March 21). Professor Vyvyan Howard and John Newby of Liverpool University argue that "low levels of chemicals from pesticides and plastics could affect the development of babies before they are born and increase their likelihood of developing cancer later in life". In fact, although the claim is intuitively appealing, it is unlikely to be true. During the three and a half years researching my book on the history and science of cancer, I found no mainstream scientific organisation that subscribes to this theory and I repeatedly met scientists who complained that there is little evidence to justify it.

And it continues like this. Link

This was the original article.

Interestingly the Guardian ran a whole pile of letters about the subject.

Flu may trigger childhood leukemia

The study finds that just a few months after two especially severe flu outbreaks in the U.K. there were sharp peaks in cases of acute lymphoblastic leukemia (ALL), a form of childhood leukemia.

This is not proof that flu causes any kind of cancer in children, stresses study leader Michael Murphy, MD, director of Oxford University's Childhood Cancer Research Group. But the findings support theories that flu and other infectious diseases might play a role in the ongoing slow-but-steady increase in ALL.

Link

Fat or Fiction

H Gilbert Welch and his colleagues describe wonderfully the problems of assessing the effects of dietary fat in The Washington Post

"The best data to date suggesting the potential for diet -- or any lifestyle alterations -- to affect cancer risk is limited. The single notable exception is smoking: There is no doubt that not smoking dramatically lowers cancer risk.

The effect of diet on cancer is likely to be small for most people because diet is so heterogeneous and the effect of any given food may depend on its interaction with other foods. And the smaller the effect, the harder it is to demonstrate statistically. So it is really not surprising that results of research about diet and cancer flip-flop. Low-fat diets probably do lower the risk of breast cancer -- but the effect on risk is small -- particularly for women with no prior history of the disease. Changing diet to reduce breast cancer -- or any other cancer -- is a personal decision, not an imperative."

Its very counter-intuitive. All the five-a-day campaigning is partly premised on the idea that better diet will reduce cancer risk. Yet the evidence about dietary fat is not quite there.

The trouble is that there is a gulf between what we know for certain and what we might presume. That said, few doctors would advise their patients anything other than switching to healthier diets for the prevention of a range of other diseases as well as cancer.