ISLAMABAD, Jul 29: Scientists believe they may have discovered why eating red meat is linked to higher chances of bowel cancer.
The pigment that gives a steak or mince its distinctive red colour is to blame, they suggest.
Haem – the part of the blood’s haemoglobin that binds in oxygen to allow it to be transported around the body – is found in much higher quantities in red meat than in white meat.
It contains iron, which produces the red colour.
The pigment that gives a steak or mince its distinctive red colour, haem, may be the reason red meat is linked to higher chances of bowel cancer, scientists have revealed. It is found in much higher quantities in red meat than in white meat
While red meat – which includes beef, lamb, and goat – has been linked to cancer for several decades, the new understanding of the mechanism by which it causes cancerous cells to form is likely to help in prevention.
The breakthrough may also create a new way to detect who is at greater risk of bowel cancer by looking for a chemical marker produced by bacteria in the gut.
Researchers from the University of Utrecht in the Netherlands discovered the link between haem and bowel cancer by feeding the red pigment to mice.
They found the mice suffered damage to their gut lining.
On closer inspection, they discovered that the bacteria in the gut were turning the haem into hydrogen sulphide.
This is the chemical which produces a smell like rotten eggs and damages the cells lining the gut.
To repair the damage, the cells rapidly regrow, but this rapid regrowth creates a greater chance of a cancerous tumour forming.
The research, published in the journal Proceedings of the National Academy of Sciences, also found that the adverse effects of eating meat were stopped by antibiotics, which kill the bacteria.
The scientists suggest that hydrogen trisulphide, a chemical produced by the gut bacteria, could be a useful chemical marker indicating who is most at risk of bowel cancer.
And they point out that 5-10 per cent of colorectal cancers are hereditary, but the majority are caused by mutations caused by environmental factors such as diet.
Breakthrough may create a new way to detect who is at greater risk of bowel cancer by looking for a chemical marker produced by bacteria in the gut
While haem increases the risk of colon cancer, other compounds in our diets also increase the risk.
Further research is needed to see if the same mechanism applies to humans, they say.
As well as preventing bowel cancer, reducing haem may also prevent other diseases of the bowel such as Inflammatory Bowel Disease.