The soy and breast cancer link faded where intake is highest
Pooling 18 studies, high soy intake went with 14 percent lower breast cancer risk across all women, but within Asian populations the same comparison missed significance.
What the study found
The protective association did not hold inside Asian countries
Pooling 18 studies, high soy intake went with 14 percent lower breast cancer risk across all women, but within Asian populations, where intake is highest, the same comparison missed significance. The authors found no dose-response and warned against reading supplements into it.
The caveat · Diet recalled after diagnosis
Twelve of the 18 studies are case-control, a design in which people recall their past diet after already knowing their diagnosis. The literature stops in 2004. Eight studies gave no menopause-specific result, and six of those did not support an association at all.