Childhood Soy and Breast Cancer Risk

Childhood Soy Intake and Breast Cancer Risk in Asian American Women.
Cancer Epidemiol Biomarkers Prev. 2009 Mar 24.

"DISCUSSION: Soy intake during childhood, adolescence, and adult life was associated with decreased breast cancer risk, with the strongest, most consistent effect for childhood intake. Soy may be a hormonally related, early-life exposure that influences breast cancer incidence."