HIGH levels of iron in the body could raise the risk of bowel cancer, a Glasgow study has discovered.
Scientists found cancers were two to three times more likely to develop in mice with faults in a critical anti-cancer gene who were fed high amounts of iron.
Mice with a faulty gene who were fed low amounts of iron did not develop bowel cancer at all.
It is thought high iron levels switch on a key cancer signalling pathway in people with faults in the APC gene, which is linked to eight out of 10 bowel cancers.
The study could explain why foods such as red meat, which have high levels of iron, are linked to an increased risk of bowel cancer.
Scientists now want to develop treatments which could reduce the amount of iron in the bowel and help cut the cancer risk.
Bowel cancer is the third most common cancer in Scotland.
Research has shown patients from the poorest areas of the West of Scotland are 24% more likely to die within five years.
Scientists have described the findings as a "huge step" in understanding how bowel cancer develops.
The study was carried out by Cancer Research UK scientists based at the Beatson Institute for Cancer Research in Glasgow and the University of Birmingham.
Professor Owen Sansom, deputy director of the Beatson Institute for Cancer Research in Glasgow, said: "We have made a huge step in understanding how bowel cancer develops.
"It's clear that iron is playing a critical role in controlling the development of bowel cancer in people with a faulty APC gene.
"And, intriguingly, our study shows that even very high levels of iron in the diet don't cause cancer by itself, but rely on the APC gene."