Physical activity and breast cancer risk markers linked in adolescent girls

January 15, 2026-- Recreational physical activity may be associated with breast tissue composition and biomarkers of stress in adolescent girls, according to a new study from Columbia University Mailman School of Public Health and the Herbert Irving Comprehensive Cancer Center (HICCC). The findings shed new light on how physical activity during adolescence—a critical period of breast development—may influence biological pathways related to future breast cancer risk.

In adult women, higher levels of recreational physical activity (RPA) are consistently linked to a lower risk of breast cancer, with studies showing roughly a 20 percent reduction in risk among the most active women compared with the least active. Until now, however, the biological mechanisms underlying this association—particularly earlier in life—have remained poorly understood. The new study provides some of the first evidence linking RPA to breast tissue composition and stress-related biomarkers in adolescent girls. The findings are published in the journal Breast Cancer Research.

“The importance and urgency of this research are underscored by the rising incidence of breast cancer in young women and the alarmingly low levels of recreational physical activity observed both in this study and among adolescents across the United States and globally,” said Rebecca Kehm, PhD, assistant professor of Epidemiology at Columbia Mailman School of Public Health, and first author of the study. “Our findings suggest that recreational physical activity is associated with breast tissue composition and stress biomarker changes in adolescent girls, independent of body fat, which could have important implications for breast cancer risk.”

Girls who reported engaging in at least two hours of recreational physical activity in the prior week, compared with none, had lower percent water content in breast tissue—an indicator of lower breast density- and lower concentrations of urinary biomarkers linked to stress. These findings align with previous research in adult women showing that higher levels of physical activity are associated with lower mammographic breast density, a key predictor of breat cancer risk.The researchers analyzed data from the population-based Columbia Breast Cancer and the Environment Research Program Study, which draws from the Columbia Center for Children’s Environmental Health (CCCEH) Mothers and Newborns birth cohort. Participants were originally recruited to the cohort between 1998 and 2006 from prenatal clinics at NewYork-Presbyterian and Harlem Hospital, as well as affiliated satellite clinics, serving urban neighborhoods including Washington Heights, Central Harlem, and the South Bronx.

During adolescence, participants self-reported past-week engagement in recreational physical activity, including both organized and unorganized activities, and completed clinic visits that included blood and urine collection as well as breast tissue assessments.

The average age of girls in the study was 16 years, and 64 percent identified as Hispanic. More than half (51 percent) reported no recreational physical activity in the past week. Seventy-three percent reported no participation in organized activities, and 66 percent reported no participation in unorganized activities.

“Our research has several strengths, including the use of multiple biomarkers measured in urine, blood, and breast tissue,” said Mary Beth Terry, PhD, Columbia Mailman School professor of Epidemiology, and senior author of the study. “We measured biomarkers of stress and chronic inflammation that are widely validated and commonly used in epidemiologic research, enhancing confidence in our findings. Importantly, this research was conducted in a population-based, urban cohort of Black/African American and Hispanic girls—groups that are historically underrepresented in research and face persistent disparities in both physical activity levels and breast cancer outcomes.”

“Our study population of urban Hispanic (Dominican) and non-Hispanic Black/African American adolescent girls is critical to include in breast cancer research,” added Kehm, who is also affiliated with HICCC. “These groups not only have been historically underrepresented in studies but they face higher risks of developing breast cancer at younger ages and of experiencing more aggressive subtypes. At the same time, Black and Hispanic girls consistently report lower levels of recreational physical activity than their non-Hispanic White peers.”

The authors note that additional longitudinal studies are needed to determine how these adolescent biomarkers may translate into breast cancer risk later in life, and say the findings underscore the potential importance of promoting physical activity early in development.

Co-authors are : Lothar Lilge, Princess Margaret Cancer Centre, University Health Network, Toronto, and University of Toronto; E. Jane Walter, Princess Margaret Cancer Centre, University Health Network;  Regina Santella, Melissa L. White, Julie Herbstman, and Frederica Perera, Columbia Mailman School of Public Health; and Rachel L. Miller, Icahn School of Medicine at Mount Sinai.

The study was supported by the National Institute of Environmental Health Sciences, grants U01ES026122 and P30ES009089; and the National Cancer Institute, grant R00CA263024.

The authors declare that they have no competing interests.

Columbia University Mailman School of Public Health

Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the third largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.