Correlation analysis was performed on breast cancer incidence and risk factors in geographical areas of Finland. Breast cancer risk is associated with fertility and taxable income but not with the size of the woman. Trends in risk factors indicate that the rapid increase in the incidence of breast cancer is likely to continue. It is concluded that factors which are reflected by the standard of living and fertility might act independently and not through the nutritional status, for which the size of the woman is an operational indicator.