Bacon, sausage and processed meats, are 'carcinogenic to humans', said a report of the World Health Organisation (WHO). [Photo/IC]

A report by the World Health Organization's International Agency for Research on Cancer has said there is enough evidence to rank processed meats - such as ham, bacon and sausages - as "group 1 carcinogens", because of their causal link with bowel cancer. Processed meats are meats that have been transformed through salting, curing, fermentation, smoking, and other processes to enhance flavor or improve preservation.

Expectedly, the IARC report has caused uneasiness among the public worldwide and its conclusion has been violently rejected by the meat industry.

"For an individual, the risk of developing colorectal cancer because of ... consumption of processed meats remains small, but this risk increases with the amount of meat consumed," said Kurt Straif, head of the IARC monograph program.

The IARC report evaluated data from more than 800 different studies of cancer risks in humans, over 700 of which involved red meat and more than 400 involved processed meat. A team of 22 international experts reviewed the evidence, and it placed processed meats in Group 1 - Carcinogenic to Humans - the same category as cigarettes. However, red meat (beef, pork, lamb) is assigned to Group 2A - Probably Carcinogenic to Humans.

Although WHO classifies processed meats and cigarettes both in the highest category of carcinogens, the classification reflects only the strength of the evidence to support this claim; it is not a reflection of the level of risk.

The difference between the risks posed by meat with or without being processed is highly significant, because processing adds several substances to the meat products that may be the real cancer causing agents. The report also doesn't make the difference between the effects of consuming meat with several additives and meat to which much fewer additives are added.