Friday, February 10, 2006


Panic: 'Red meat cancer risk clue found,' says BBC News reporting on a new study which suggests a mechanism by which eating beef, pork and other red meat might increase the risk of bowel cancer. A small group of volunteers were fed three different diets: one in high in meat but low in fibre; high meat and high fibre; and no meat. Those in the high meat, low fibre group had significantly greater damage to the DNA in their colon than the other groups. The researchers, from the Dunn Human Nutrition Group and the Open University, suggest that N-nitrosocompounds, substances formed in the gut after consuming red meat, may be responsible.

This study follows a report published in 2005 that suggested that those who ate red meat twice a day were a third more likely to develop bowel cancer than those who ate red meat less than once a week. Cancer of the bowel causes 16,000 deaths in the UK each year.

Don't panic: This new study is only suggestive of a possible cause for why red meat might cause cancer. The link is far from proven, and if there is an increased risk it would appear to be small.

The study obliged volunteers to eat 420g of red meat each day for two weeks. That is an unusually large quantity of meat - roughly equivalent to eating four quarterpounders a day. Moreover, the small number of subjects involved and the short timescale suggest more work is required.

Even if this mechanism suggested was to be confirmed, the risks are still small. The 2005 study found that the annual risk of bowel cancer at the age of 50 for the high meat consumption group was 0.17 per cent, compared to 0.12 per cent for the low meat consumption group. Either way, bowel cancer is not a major threat for most people. While such figures translate into large numbers at a population level, they are fairly meaningless as a guide to individual behaviour.

Other factors are important, particularly age - 80 per cent of bowel cancers occur in people over the age of 60 - and survival rates have improved a lot in the last few years. So, chances are you can carry on scoffing the bacon sandwiches and beefburgers, and still live to a ripe old age.


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