WIKIMEDIA, 14 MOSTAFA&ZEYADMore than two centuries ago, the brilliant English surgeon Percivall Pott became intrigued by a scrotal cancer that disproportionately afflicted former chimney sweeps. Pott argued in a book initially published in 1775 that exposure to soot caused the disease, making him the first person to identify an environmental cause of cancer. His observation helped lay the foundations of occupational medicine and, notably, suggested that the chimney sweeps’ cancer could be prevented.
Today we know significantly more about the causes of cancer, and these are, if nothing else, as complex as the disease. How exactly genes and environment interact to propel malignancy is only just beginning to be worked out, but one thing is clear: our habits play a big role. We know, for example, that about half of all diagnosed cancers are fueled by lifestyle choices, such as smoking, alcohol use, and poor diet, but the answer is probably more nuanced than we realize. What constitutes a good versus poor diet, for instance? A huge study published in JAMA Internal Medicine earlier this month (March 9) reported that people who eat fish have a 43 percent reduced risk of colon cancer compared with those who eat ...
