Chromium is the transition metal that occurs most frequently on the two main oxidation states – as trivalent Cr(III) and hexavalent Cr(VI). Chromium in the form of a trivalent is a trace element necessary, among others for paralytic glucose metabolism, because it is the glucose tolerance factor. On the other hand, exposure to Cr(VI), mainly in industry, poses a serious threat to health, because it has been recognized as a carcinogen with proven carcinogenicity for humans. Recently, the importance of chromium is more and more controversial, not only because of the pro-carcinogenic activity of Cr(VI), but also because of the indicated side effects of trivalent compounds, which is particularly important due to their widespread, often uncontrolled intake of dietary supplements, nutrients for athletes and diet products. The article reviews available literature on the importance of chromium, its advantages and disadvantages to the functioning of the human body. The effects of excess and deficiency of this element and the importance of Cr(III) in medicine and pharmacy have been characterized. The market research on dietary supplements containing chromium (III) compounds, currently available in Poland, was conducted, analyzing 88 various preparations.

Keywords: trivalent chromium, hexavalent chromium, dietary supplements.