A growing body of research suggests that processed meats such as bacon, sausages, hot dogs and cold cuts could increase the risk for cancer. Now the high-profile World Health Organization has weighed in on the topic, releasing a report that reinforces those findings.
The report, released Monday by the WHO's International Agency for Research on Cancer, labels processed meats Group 1 carcinogens due to a causal link between consuming processed foods and colorectal cancer. The report was published in the UK Medical Journal The Lancet Oncology.
Being categorized as a Group 1 carcinogen puts processed meats on par with known carcinogens asbestos, arsenic, alcohol and tobacco. The risks associated with smoking and alcohol are far greater than that of processed meats, the WHO said.
"These findings further support current public health recommendations to limit intake of meat," IARC Director Dr. Christopher Wild said in a statement. "At the same time, red meat has nutritional value. Therefore, these results are important in enabling governments and international regulatory agencies to conduct risk assessments, in order to balance the risks and benefits of eating red meat and processed meat and to provide the best possible dietary recommendations."
The North American Meat Institute, a trade association that represents US packers and processors of beef, pork, lamb, veal and turkey, questioned the validity of the study, stressing that "scientific evidence shows cancer is a complex disease not caused by single foods and that a balanced diet and healthy lifestyle choices are essential to good health."
"It was clear, sitting in the IARC meeting, that many of the panelists were aiming for a specific result despite old, weak, inconsistent, self-reported intake data," Betsy Booren, vice president of scientific affairs at the institute, said in a statement released Monday.
"Followers of the Mediterranean diet eat double the recommended amount of processed meats. People in countries where the Mediterranean diet is followed, like Spain, Italy and France, have some of the longest lifespans in the world and excellent health," she added.
To arrive at the Group 1 categorization, a group of 22 scientists from 10 countries reviewed over 800 studies on processed meats, and found strong, sufficient causal evidence linking processed meats with an increased risk of colorectal cancer.
It doesn't take much processed meat consumption to increase risk, according to the report. It concludes that "each 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by 18 percent," which is about 2 slices of uncooked bacon (depending on the cut). The group defines processed meat as meat that "has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavor or improve preservation."
The report also found a weaker link between red meat and colorectal, pancreatic and prostate cancers. The WHO gave red meat a Group 2A rating, suggesting that those foods probably carry an increased risk for cancer, but with only limited evidence to support a causal link between them.