Covariance of breast cancer incidence with smoking-, oestrogen- and diet-related cancers in pre- and postmenopausal women in Sweden
Effects of smoking on breast cancer risk remains controversial. Tar products have been claimed to increase risk, antioestrogenic effects to reduce risk. Another possibility is that associations to smoking have been confounded by diet. The increasing incidence of breast cancer from 1960 to 1994 in Sweden is parallel to that of lung cancer and the increasing proportion of female smokers. The inciden
