You take supplements to stay healthy
— but some of them may be doing more harm than good.
Certain dietary iron supplements may aid the development of colon cancer in humans, according to new research
out of Sweden’s Chalmers University of Technology.
Scientists found that two strains of iron — ferric citrate, which is found in vitamin supplements, and ferric EDTA, a food additive — encouraged the formation of a biomarker associated with long-term cancer and early death.
The Swedish researchers partnered with the UK Medical Research Council and Cambridge University to examine the effect these two iron compounds have on human colon cancer cells. They compared those results with those of ferrous sulphate, another common iron strain that’s generally considered safe.
Even at low doses, results showed that ferric citrate and ferric EDTA increased levels of the cancerous biomarker, while ferrous sulfate made no difference.
“We can conclude that ferric citrate and ferric EDTA might be carcinogenic,” study co-author Nathalie Scheers, assistant professor at Chalmers, says in a press release.
Unfortunately, it’s hard to act on their findings. Many supplement manufacturers don’t even note the type of iron being used in their products on their labels. Still, it doesn’t hurt to check, says Scheers.
“At the moment, people should still follow recommended medical advice
,” she says. “But speaking personally, if I needed an iron supplement, I would try to avoid ferric citrate.”