Concentrations of iron similar to those delivered in standard treatments such as tablets and infusions may trigger DNA damage within 10 minutes, a new study has claimed.
Iron is essential for the body to function and has a crucial role in transporting oxygen - low levels cause anaemia which leads to tiredness and lethargy.
Iron tablets, which are available over the counter or on prescription, are taken by millions of people around the world.
For the study, researchers from Imperial College in UK used human endothelial cells, which line blood vessels, and added a placebo or an iron solution of 10 micromolar (a similar concentration to that seen in the blood after taking an iron tablet).
Through looking at genes used within cells, and then examining the cells in more detail, they found that within 10 minutes, cells treated with the iron solution had activated DNA repair systems. These were still activated six hours later.
The amount of iron given in standard treatments, such as tablets and infusions, and the effects this could be having on the body needs to be carefully looked at, researchers said.
"We found that when we applied the kinds of levels of iron you would find in the blood stream after taking an iron tablet, this also seemed to be able to trigger cell damage - at least in the laboratory," said Claire Shovlin from Imperial College.
"At the moment, each standard iron tablet contains almost 10 times the amount of iron men are recommended to eat each day - and these dosages have not changed for more than 50 years.
"This research suggests we may need to think more carefully about how much iron we give to people, and try and tailor the dose to the patient," she added.
Researchers initially started studying this area after finding that a small proportion of people using iron tablets for the condition hereditary haemorrhagic telangiectasia, which causes abnormalities in the blood vessels, reported their nose bleeds got worse after iron treatment.
The findings were published in the journal PLOS ONE.
