Mon Mar 17, 5:30 PM ET Yahoo


By Linda Carroll

NEW YORK (Reuters Health) - Chromium picolinate, a popular supplement marketed as building muscle and promoting weight loss, may damage DNA, a new study shows.


Consumption of the supplement led to lethal genetic mutations and sterility in fruit flies, according to a study published in the advance online edition of the Proceedings of the National Academy of Sciences (news - web sites).


Previous studies suggested that chromium picolinate might cause DNA damage in rats, said study co-author John Vincent, a professor of chemistry at the University of Alabama in Tuscaloosa.


But there were questions as to whether this kind of DNA damage was mild and could be repaired by the body or whether it might lead to mutations that would be passed on to offspring, Vincent said in an interview with Reuters Health.


To answer this question, Vincent and his colleagues raised four generations of fruit flies on a medium containing chromium picolinate.


In each generation, 20 percent to 30 percent fewer flies reached adulthood among the group fed chromium picolinate, compared to those not given the supplement.


In another experiment, the researchers fed chromium picolinate only to the male flies. "Then we looked at the effect of that on the flies' grandchildren," Vincent said. "Two generations removed there were very high rates of mutations."


Among the first two generations of flies fathered by the males fed chromium picolinate, the researchers found fewer male progeny and an increased number of sterile females.


The research is at odds with the popular conception that chromium picolinate is a safe supplement. Currently, the Food and Drug Administration (news - web sites) doesn't require testing of dietary supplements before they are marketed.


"I think this research suggests that the FDA might want to take another look at chromium picolinate," Vincent said.


The Council for Responsible Nutrition (CRN), a trade association of the dietary supplement industry, issued an announcement in response to the publication of the study. "The University of Alabama study, in which fruit flies were given high concentrations of chromium picolinate, provides no meaningful conclusions that change the weight of the strong scientific evidence for safety in humans," said Dr. John Hathcock, CRN's vice president, scientific and international affairs, in the statement.


In Hathcock's review of relevant studies, he found no adverse effects in people taking up to 1,000 micrograms of chromium picolinate per day.


Vincent allows that there might be a difference between humans and fruit flies when it comes to evaluating the impact of the supplement on DNA. Still, he sees the results of his study as a warning sign.


"I'm not a physician and so I can't give medical advice," Vincent said. "But I personally wouldn't take it."


SOURCE: Proceedings of the National Academy of Sciences 2003;10.1073/pnas.0636646100.