Possible protective role of trace elements in human cancer: a review of recent epidemiological studies

The interest in the role of trace elements in cancer is increasing, particularly for those with a possible protective action, such as selenium and zinc. Despite the vast amount of epidemiological studies already conducted, there is a need for further investigations to better understand what compounds, at what levels and with which mechanism trace elements are involved in the protection of a specific cancer or groups of cancer. From our studies, we observed that cancer type and patient characteristics can substantially affect plasma concentrations of trace element status. A better evaluation of the body burden of trace elements should include analysis of other indicators such as hair, cells or tissue specimens, which tends to reflect long-term exposure th these elements.