Breast cancer risk markedly lower with serum 25-hydroxyvitamin D concentrations ≥60 vs <20 ng/ml (150 vs 50 nmol/L): Pooled analysis of two randomized trials and a prospective cohort

Dose dependent reduction in breast cancer incidence with the largest reductions in risk (decrease of 82%) was found women with the highest concentration of vitamin D (≥60 ng/ml).
This study indicates that higher doses of vitamin D PROTECTS against the development of breast cancer.
One StarPower tablet will get your blood levels to approximately 50 ng/ml.

Take home message: The graph says it all. BC incidence decreases as vitD concentration increases.