Processed meats such as sausage can lead to colon and other cancers. [Photo: dodocook.com]

The World Health Organisation's cancer agency says processed meats can lead to colon and other cancers, and red meat is also a likely cause of the disease.

Researchers from the WHO's International Agency for Research on Cancer, or IARC, in Lyon, have released an evaluation of more than 800 studies from several continents about meat and cancer.

Dr Kurt Straif with IARC introduces the study results.

"From the combined analysis of several studies there was about a 17 percent increase of cancers of the colorectum per portion of about 50 grams per day of processed meat. Now that increased risk is about similar for red meat - it's 1.17 per 100 grams - but again the evidence if it's really causally related is not as strong yet."

Based on the evaluation, processed meat is classified as "carcinogenic to humans" - in the same category as tobacco, asbestos and diesel fumes- and red meat as "probably carcinogenic to humans."

Dr. Dana Loomis of the IARC explains that it doesn't mean processed meat is as risky as smoking.

"But it's important to recognize that those classifications relate to the strength of scientific evidence for carcinogenicity and not to the level of risk. So even though they are all on the same category, the level of risks for tobacco smoking is much larger than the risk associated with eating meat, ten times larger than the risk for processed meat, for example."

The Global Burden of Disease Project says if the cancer link with red meat were confirmed, diets rich in red meat could be responsible for 50,000 deaths a year worldwide.