When George W Bush declared a war on terror in 2001 he was following the lead of his predecessor Richard Nixon, who in 1971, looking for similar rhetorical effect, declared a war on cancer. A new book by environmental health expert Devra Lee Davis explains why Nixon's war is still being lost: too many tactics, not enough strategy; too much focus on treatment, not enough on prevention.

There have been spectacular advances in the understanding and treatment of cancer, some of them reported in these pages. But Davis, who heads up the Center on Environmental Oncology at the University of Pittsburgh Cancer Institute [1], points out that one in two men and one in three women in the US will die of cancer, even so. The situation is worse for African Americans and for certain other minorities.

Where progress has been made, for example in reducing diagnosed cases of breast cancer, Davis points to significant improvements in environmental risk, such as the dramatic fall by around 40 million in the early part of the present decade, in the number of prescriptions for hormone replacement therapy in the US.

But many obvious prevention strategies, such as getting people to exercise more, eat more healthily and to take fewer drugs – alcohol included – are less prominent in the US government’s arsenal.

Devra Davis's book has been the subject of some controversy in the US. She doesn’t pull her punches, and some have landed on trusted treatments and revered figures.

Among her targets is the drug Ritalin, taken by an estimated 10% of US children to combat the symptoms of poor attention and hyperactivity. Parents like the way they drug improves their children's attention and the better school grades that seem to follow. But Davis claims that many are unaware of the potential genetic and carcinogenic risks of Ritalin. When tested with animals, for example, it appears to be linked to an increase in liver cancers.

As unpopular – although she is by no means the first to take it – is her swipe at a doyen of the prevention world, the late Professor Richard Doll. His paper with Austin Bradford Hill in the British Medical Journal in 1950 firmly established the link between smoking and lung cancer. Doll's work laid the foundations for some of the biggest breakthroughs in the epidemiology of cancer, and one of the greatest public health revolutions, the gradual reduction in smoking. [See Is there still a message in the bottle? [2]]

But Davis brings to attention Doll's close connections later in his life with industrial interests and to allegations after his death that he may have skewed his reporting on other risk agents, such as asbestos.

Putting the controversy to one side, the opportunities to prevent adult health problems during childhood are clear. A war on obesity and another on teenage smoking might be a war well worth fighting, at home and abroad.

Michael Little

References
Devra Davis, The Secret History of the War on Cancer, Basic Books, 505pp
Richard Doll and A. Bradford Hill, “Smoking and Carcinoma of the Lung”, British Medical Journal, 2, 739-748, 1950

• The allegations about Sir Richard Doll’s industrial connections, for example with Monsanto, who developed the notorious Agent Orange, and with the asbestos company Turner and Newall, received wide coverage after his death in 2005. The disclosures are generally balanced by the counter-argument, for example as put by Professor John Toy, medical director of Cancer Research UK, that Doll’s lifelong service to public health had saved millions of lives. [See for example: Telegraph.co.uk article: chemical firm 'paid cancer pioneer' [3]]