Dr Kurt Straif, Head of the IARC Monographs Programme, comments on the Working Group’s evaluation of the carcinogenicity of the consumption of red meat and processed meat.

What is the outcome of the Volume 114 evaluation?

The outcome of this evaluation is that the Working Group concluded that consumption of processed meat is carcinogenic to humans, and this was based primarily on strong evidence that consumption of processed meat causes colorectal cancer. There was also an association observed with stomach cancer. Then the Working Group also evaluated the consumption of red meat, and there, there was also a positive association from several epidemiological studies, but not as strong evidence as for the processed meat, and therefore this was evaluated as Group 2A, probably carcinogenic to humans.

How did the Working Group define red meat and processed meat?

The Working Group for this evaluation defined red meat as all muscle meat from mammals, such as beef, veal, pork, goat, lamb, and the like. Processed meat is raw meat that has been transformed by any of several methods, including curing, salting, smoking, and also fermentation.

Could the Working Group quantify the risk associated with consumption of processed meat?

The Monographs Programme really looks if some exposure can in principle cause cancer in humans, but this meeting also allowed the Working Group to look more specifically at the risk increase in persons that ate processed meat or red meat, and this comes from large combined analyses of many, many epidemiological studies, and that shows that consumption of about 50 grams of processed meat per day increases your risk by about less than 20%.

How big is the risk associated with consumption of red meat and processed meat?

This is a small risk, about the order of magnitude of the risk of passive smoking and lung cancer, for example. But we have to keep in mind that the exposure is very common because many people eat processed meat or red meat, and therefore it is still of public health importance.

Why did the IARC Monographs Programme choose to evaluate red meat and processed meat?

There is concern about cancer-causing effects of different types of diets, and a recent Advisory Group meeting to the Monographs Programme, because of that, recommended that processed meat and red meat should be evaluated by the Programme with high priority.