Risky Chromium Therapy

  • Author: Angewandte Chemie International Edition
  • Published Date: 07 January 2016
  • Source / Publisher: Angewandte Chemie International Edition/Wiley-VCH
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
thumbnail image: Risky Chromium Therapy

Potential Risks of Chromium(III) Dietary Supplements

Chromium supplements are widely consumed for their antidiabetic activity as chromium(III) enhances the insulin sensitivity of cells. In particular, orthomolecular practitioners believe in the beneficial effects of providing the body with extra amounts of essential trace elements. As Australian and American scientists now report in the journal Angewandte Chemie, chromium(III) dietary supplements are oxidized to a certain extent in living cells to their carcinogenic and genotoxic chromium(V) and chromium(VI) counterparts, which raises questions about potential risks of such therapies.


Fate of Chromium Compounds After Their Intake

In the body, chromium(III) is known to be able to enhance the effects of insulin and oral antidiabetic drugs. Thus it has been proposed that the daily intake of a certain amount of chromium lowers the blood glucose level. However, in higher oxidation states, chromium compounds can have detrimental effects on DNA and thus can cause cancer. There is growing concern about possible oxidation pathways during the metabolic transformation of the chromium(III)-containing drugs in the cell.

With the aim at getting more insight into the fate of the chromium compounds after their intake, Peter A. Lay from the University of Sydney, Australia, and his colleagues employed X-ray fluorescence microscopy (XFM) elemental mapping and microfocus X-ray absorption near-edge structure (µ-XANES) analysis on single chromium(III)-treated adipocytes, making use of the Australian Synchrotron facility and of resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility.

By carrying out XFM analysis, Lay and his colleagues found that the chromium was confined in "hotspots", and the µ-XANES data revealed that these hotspots did not only contain chromium(III). The researchers conclude: "This finding unambiguously confirmed the presence of high oxidation states of chromium." After having established the presence of higher oxidation states, the scientists also modelled the possible chromium compounds and identified chromium(V) and chromium(VI) compounds.


Effects on Health

The question remained why the chromium was oxidized in the overall reducing environment of the cells. The researchers present a possible and plausible explanation: During cell signaling, and especially insulin signaling, strong oxidants such as hydrogen peroxide are formed, which will trigger the formation of reactive chromium(V) and chromium(VI) intermediates. "This raises concern over the possible carcinogenicity of chromium(III) compounds and the risks of long-term chromium(III) nutritional supplementation," the authors say.

Although concerns have been raised for some time about the efficacy and safety of such supplements, many authorities and a large community of orthomolecular practitioners still recommend such treatments. Thus Lay and his colleagues urge for future studies: "In light of these findings, there is a need for epidemiological studies to ascertain whether chromium(III) supplements alter cancer risk."

Article Views: 2502

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

Bookmark and Share

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission. more


ChemistryViews.org on Facebook

ChemistryViews.org on Twitter ChemistryViews.org on YouTube ChemistryViews.org on LinkedIn Sign up for our free newsletter

Magazine of Chemistry Europe (16 European Chemical Societies)published by Wiley-VCH