Physical inactivity, poor diet, excessive alcohol consumption, and smoking are modifiable risk factors associated with development of chronic diseases. Although the prevalence of diseases associated with these detrimental lifestyle behaviors is high among women in the United States, they may not receive adequate counseling from physicians. To predict physicians' lifestyle counseling practices, we assessed personal, professional, and health behavior characteristics from responses to a self-administered survey of breast cancer risk reduction practices. Subjects were California physicians identified through AMA Masterfile, in family practice, internal medicine, or obstetrics/gynecology, who were asked to report the percentages of women patients they counseled on physical activity, diet, alcohol, and smoking. Of 1647 eligible physicians, 822 (50.0%) responded. Fifty-six percent reported counseling at least 75% of patients about physical activity, 54.6% about diet, and 44.8% about alcohol. More than three quarters (78.7%) counseled at least 75% of patients about smoking. In logistic regression analyses, woman gender, family practice, and internal medicine specialties emerged as significant predictors of counseling for all lifestyle behaviors. Older age was associated with dietary and alcohol counseling. Race/ethnicity was associated only with smoking counseling, and country of medical school was associated with counseling for physical activity and smoking. Sources of new medical knowledge emerged as predictors for all types of counseling, whereas physicians' own level of physical activity only predicted counseling about physical activity. Physicians' personal, professional, practice, and health behavior characteristics were associated with reported lifestyle counseling of women patients. Results reveal important directions for future physician-based interventions to improve counseling.