The surgeon general report on smoking and health 50 years later: breast cancer and the cost of increasing caution.

Despite the Surgeon General's strong track record and the rapidly expanding body of solid scientific work demonstrating that smoking caused a wide range of diseases, the decision making process for concluding "causality" in Surgeon General reports has become increasingly cautious and defensive. Whereas, the 1964 report did not conclude that smoking caused heart disease, it recommended that "from the public health viewpoint [one should] assume that the established association has causative meaning rather than to suspend judgment until no uncertainty remains," the de facto practice has become to do just the opposite. In particular, the 2004 report reached an affirmative negative conclusion that active smoking did not cause breast cancer and the 2006 report on passive smoking only found the link "suggestive." In contrast, in 2005 the California EPA found both active and passive smoking caused breast cancer in younger women. The evidence has continued to strengthen since 2005: there are now 12 large cohort studies that consistently demonstrate a dose-response relationship with smoking before first birth and increased breast cancer risk. The Surgeon General's increasing caution is preventing young women around the world from appreciating the risks that smoking and secondhand smoke pose for developing breast cancer.