The new study, published by the American Assn. for CancerResearch and released Thursday, found that among 55,987post-menopausal women, the one-third with the highest cadmium intakes were 21% more likely to develop breast cancer than the one-third with the lowest intakes.
Cadmium is a metal commonly found in the environment. It is also found in many farm fertilizers.
Dietary cadmium can be found in whole grains, potatoes, other vegetables and shellfish. When cadmium works its way into foods, the metal can have estrogen-like properties, known to be toxic and, in certain forms, carcinogenic, and leads to risk of breast cancer growth.
In brief, there is still not proved cause and effect of dietary cadmium and breast cancer risk, so that the findings are not a reason to avoid vegetables and whole grains, the researchers say. In fact, they found that women in the study who ate a lot of whole grains and vegetables had a lower risk of breast cancer compared to women who were exposed to the cadmium through other foods.
The grains and vegetables may protect against breast cancer because of their antioxidant properties and in other ways, the researchers say.