Interesting press release from WHO that eating processed meat increases potential for colon cancer.
http://www.who.int/features/qa/cancer-red-meat/en/
The quoted eating “50g of processed meat can increase your changes by 18%”, evening assuming that the studies reviewed do show causation not just a relationship, the vital bit of information is what is the new risk.
In Wikipedia there is a statement that based on late 2000 data from America around 4% of men and women born around then will experience some form of colon cancer.
Hence we have a risk of 0.04 x 1.18 = 0.047, near 5%, which does seem a lot of people, the vast majority would occur over 50 years of age, incidence and mortality, and we have not idea of the world wide factors.
Causes would be multi-faceted, and the reference below, from the US shows a decline in most population areas but that Afro-American’s have a higher rate of noth incedence and resultant mortality. There are also other interesting demographic differences e.g. Alaska has a much higher rate.
The press release from WHO does not give sifficient detail and will simply cause problems with interpretation.
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