Scientific Evidence Portal
Cigarette smoking and breast cancer | JA Baron, PA Newcomb, MP Longnecker, R Mittendorf, BE Storer, RW Clapp, G Bogdan and J Yuen
Article Published: 1996
Risk: RR = 1.00, 1.10
Funding Source: US Public Health Service
Significance: No Risk Change
Published By: Cancer Epidemiology Biomarkers & Prevention, Vol 5, Issue 5 399-403
virtually no relationship between current smoking and breast cancer risk (multivariate odds ratio, 1.00; 95% confidence interval, 0.92-1.09), and former smokers had a barely increased risk (odds ratio, 1.10; 95% confidence interval, 1.01-1.19). Similar results were observed among both premenopausal and postmenopausal women. There was no suggestion that heavy or long-term smoking increased or decreased risk, nor were there indications that women who began smoking at an early age were at increased risk, as has been hypothesized. The results of this large population-based study indicate that smoking does not influence the risk of breast cancer, even among heavy smokers who began smoking at an early age."
Emphases added above. The authors comment: "Indeed, most previous studies have noted that cigarette smokers in general are not at substantially altered risk of breast cancer incidence compared to nonsmokers, conclusions that agree with our findings." And: "Thus, in aggregate, there appears to be no association of early smoking with breast cancer risk, even among heavy smokers ... Also, our questionnaire did not include items regarding passive smoking, but in the absence of an effect of active smoking, a major impact of such smaller exposures is implausible."
This huge study was supposed to close the debates on whether smoking did or did not "cause" breast cancer – and that would have been the case if ideology and pharmaceutical interests were not involved. Because the antismoking propaganda has little to do with real science, however, still today we hear that smoking is a major cause of breast cancer. It sure is false, but it sure is scary.