en <span style=line-height:normal><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Aims:</span></span></span></b><span style=font-size:10.0pt><span style=font-family:Cambria,serif> A healthy lifestyle is a crucial modifiable risk factor in breast cancer prevention. This study aimed to identify predictors of health-promoting behaviors based on the self-regulation model among breast cancer patients in northern Iran.</span></span></span><br> <span style=line-height:normal><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Instrument & Methods:</span></span></span></b><span style=font-size:10.0pt><span style=font-family:Cambria,serif> This cross-sectional analytical study was conducted in 2021 involving 260 breast cancer patients. A questionnaire assessed demographic characteristics, disease status, psychosocial factors related to the self-regulation model, health-promoting behaviors, and patients’ attitudes toward their health. Data were analyzed using correlation coefficients and multivariate linear regression.</span></span></span><br> <span style=line-height:normal><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Findings:</span></span></span></b> <span style=font-size:10.0pt><span style=font-family:Cambria,serif>The average age of participants was 52.6±10.6 years. A direct correlation was found between perceived treatment effectiveness and all domains of health-promoting behaviors. The multivariate regression model indicated that perceived treatment effectiveness significantly predicted health-promoting behaviors, including a healthy diet (β=0.20, p=0.016), vitamin consumption (β=0.21, p = 0.002), and performing mammography (β=-0.26, p=0.001).</span></span></span><br> <span style=line-height:normal><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Conclusion:</span></span></span></b> <span style=font-size:10.0pt><span style=font-family:Cambria,serif>Perceived treatment effectiveness is closely linked to enhanced health-promoting behaviors. </span></span></span><br> Health Promoting Behaviors,Patients,Breast Cancer, 71 79 http://hehp.modares.ac.ir/browse.php?a_code=A-10-86850-1&slc_lang=en&sid=4