The Association Between Diet-Physical Activity Patterns and Breast Cancer: A Cross-Sectional Study From NHANES 2007 to 2018.

BACKGROUND

Breast cancer (BC) remains a leading global health burden, with lifestyle interventions emerging as critical modifiable risk factors. Despite evidence supporting the independent roles of diet and physical activity (PA) in BC prevention, their synergistic effects remain underexplored.

METHODS

This study used data from the National Health and Nutrition Examination Survey 2007 to 2018 to identify diet-PA clusters and evaluate their associations with BC risk. About 1488 participants were included, comprising 186 BC cases and 1302 non-BC cases. Nutrient intake and PA (walking/bicycling, work activity, recreational activity, measured as metabolic equivalent [MET]-min/wk) were standardized, then dimensionally reduced via principal component analysis (PCA) to retain components explaining > 80% variance. K-means clustering was applied to these components to identify diet-PA clusters, and multivariable logistic regression models assessed the association between clusters and BC risk, adjusting for demographic, lifestyle, and socioeconomic confounders. Sensitivity analyses were conducted to verify results robustness.

RESULTS

PCA yielded 5 principal components explaining 82.3% of variance, with clustering defining 10 nutrient-PA profiles. Cluster 6, characterized by high work activity, moderate fiber intake, and low sugar, had the lowest BC prevalence (0.5%). Cluster 5, marked by low energy intake and unbalanced PA, showed the highest risk in fully adjusted models (23.7%). Protective clusters correlated with diverse PA and balanced nutrients, while high-risk clusters featured sedentary behavior and poor dietary quality. Sensitivity analyses confirmed robust results.

CONCLUSION

This study identified distinct diet-PA clusters associated with BC risk. Moderate dietary fiber intake and low sugar consumption during high-intensity work emerged as protective factors.