Chromium is most frequently used in supplement form for weight management, body building and type 2 diabetes. Now UNSW and University of Sydney research has revealed that chromium is partially converted into a carcinogenic form when it enters cells, prompting concerns about commonly taken dosages.
The Australian National Health and Medical Research Council recommend 25-35 micrograms of chromium daily as an adequate adult intake. The US National Academy of Sciences advises that a maximum of 200 micrograms of chromium a day is considered safe.
Some commercially available tablets have been found to contain up to 500 micrograms of chromium each.
The research, published in the chemistry journal Angewandte Chemie, was conducted on animal fat cells, which were x-rayed to allow scientists to observe the behaviour of chromium within the cell.
"We were able to show that oxidation of chromium inside the cell does occur, as it loses electrons and transforms into a carcinogenic form," said UNSW's Dr Lindsay Wu.
"This is the first time oxidation was observed in a biological sample with the same results expected in human cells."
The researchers say more study is needed to conclusively say whether the supplements significantly alter cancer risk.