Higher blood level concentrations of vitamin D have been linked to significant reduction in the risk of breast cancer, according to a study published this month in the International Journal of Cancer.

“The anti-carcinogenic potential of vitamin D in various cell types, including normal and malignant breast cells, by influencing the induction of cell differentiation, inhibition of cell growth and regulation of apoptosis, is well established,” Dr. Jenny Chang-Claude told Reuters News service. Chang-Claude, with colleagues at the German Cancer Research Center in Heidelberg, conducted the study.

In the study, Vitramin D blood levels were 45.4 nmol/L (nanomoles per liter) in the women with breast cancer and 51.3 nmol/L in a control group. (There are two ways to measure blood levels — in nmol/L and ng/ml, or nanograms per milliliter. Simply, 1 ng/ml = 1.5 nmol/L.) Pre-menopausal women were studied.

“The findings suggest that vitamin D has a protective effect in pre-menopausal breast cancer, and the investigators recommend further examination of the effects of progesterone receptor status,” Reuters reported.