Could your iron tablets be doing more harm than good?

Iron levels similar to those found in many standard treatments can trigger DNA damage in cells, according to new research by scientists from Imperial College London.

The researchers, writing in the journal PLOS ONE, found that DNA cells experienced damage within 10 minutes when exposed to iron in the laboratory. This suggests that the amount of iron given in tablets and infusions needs to be considered carefully, as it could be having a greater effect on the body than was previously realised.

Iron tablets, which are available over the counter or on prescription, are taken by millions of people in the UK – six million prescriptions issued every year in England and Wales alone.

The research was prompted after it was realised that a small proportion of people using iron tablets for blood vessel abnormalities reported their nose bleeds got worse after iron treatment.

The researchers 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 ten minutes, cells treated with the iron solution had activated DNA repair systems. These were still active six hours later.

Dr Claire Shovlin, the study’s senior author, said:

‘We already knew that iron could be damaging to cells in very high doses. However, in this study 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. In other words, cells seem more sensitive to iron than we previously thought.

‘This is very early stage research, and we need more work to confirm these findings and investigate what effects this may have on the body. We are still not sure how these laboratory findings translate to blood vessels in the body. We’re not at the stage yet where we would advise doctors to change their approach to prescribing iron supplements. Many people need extra iron – it is crucial to allow our bodies to function properly – and anyone with any concerns about their iron supplements should talk to their healthcare provider.’