Chapter 2 What Causes Cancer: Cancer

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Chapter 2: What causes cancer

If cancer is a mystery to be solved, then epidemiologists are the detectives who have turned up the clues and identified the major suspects. Epidemiologists are physicians and scientists who study disease in large populations, analyzing such details as age, gender, weight, and lifestyle choices, and attempt to determine what the victims of a disease had in common. Out of these studies, patterns emerge - and these patterns provide valuable insights into what inborn qualities or acquired habits might put someone at risk for a disease. Although the field of epidemiology originated with the study of epidemic diseases, such as cholera or plague (hence the name epidemiology), it has expanded to include the study of other diseases such as cancer.

Scientists have identified a number of causes for cancer. However, by nature, epidemiology is probabilistic: it studies the probability or the likelihood that disease will occur within a population, in other words, groups rather than individuals. So the information about what puts you at risk for cancer, or how you might reduce your risk, is based on statistical analyses of the population as a whole. While there is no way to know for certain what will happen to you as an individual, you can remove some risk by identifying risk factors and following general guidelines to avoid danger. For example, you cannot prevent an automobile accident by wearing a seat belt but you can substantially reduce your risk of severe injury and death by always using it.

Last updated:	May 01, 2008