Posted Friday, Nov. 13, 2009, at 1:03 PM
Gina Kolata points out , once again, that diet and exercise have not been shown to affect breast cancer rates. Massive, well-run observational studies and randomized controlled trials turn up nothing. This finding appears to be unacceptable; popular culture rejects it utterly. Women’s magazines continue to preach the holy gospel of five fruits and vegetables a day. Doctors continue to tell patients at high risk of breast cancer that diet matters. The director of one of the (fruitless?) studies tells Kolata that doctors need to "rethink the studies." Diet and exercise "are likely quite important, but we just aren’t getting the answers."
Maybe, says the chairman of the department of epidemiology at Memorial Sloan-Kettering Cancer Center. Or maybe "It’s all sort of nonsense to begin with."
The question is why people so desperately want to believe, in the absence of evidence, that vegetables and treadmills will shield them from cell division. Says surgeon Susan Love, "It’s wishful thinking ... we would like things to be more in our control."
But it must be something more, because drugs that do help prevent breast cancer-that do put patients in control in a way that accords with scientific findings-go ignored. The drug Tamoxifen cuts the cancer rate in half . The drug Evista does the same, with reduced risk of side effects. And one need only continue the treatment for five years. "It was a spectacular clinical trial," reports a crestfallen Victor Vogel, who helped run the study. But no one cared: "The world said, so what?" Few doctors bother to recommend the drugs to women at a high risk of breast cancer, and when they do, patients often do not fill their prescriptions. The drugs are not expensive. The message sent to drug companies is that there is no market for cancer prevention drugs, so don’t sink millions into developing them.
My own view is that we want to be in control only in a way that conforms to certain notions of virtue. Eating a healthy diet, exercising regularly, and abstaining from alcohol are all behaviors that suggest a kind of moral rectitude absent from pill-popping. Popular media delights in reporting that smokers vastly increase their risk of various diseases; it seems that this is how things ought to be-indulge and be punished. Taking a pill called Tamoxifen every morning does not suggest anything of virtue or self-denial. It suggests, perhaps, cheating.
We'll take pills to prevent ailments framed as the natural and blameless consequence of aging, as with heart disease. But cancer-swift, random, terrifying-we still regard as cosmic punishment.