The hyper-precautionary International Agency for Cancer Research, a arm of the World Health Organization, has just declared that processed meats are definitely human carcinogens. Steak and chop lovers are also warned that red meat is probably a human carcinogen. From the IARC press release:
After thoroughly reviewing the accumulated scientific literature, a Working Group of 22 experts from 10 countries convened by the IARC Monographs Programme classified the consumption of red meat as probably carcinogenic to humans (Group 2A), based on limited evidence that the consumption of red meat causes cancer in humans and strong mechanistic evidence supporting a carcinogenic effect.
This association was observed mainly for colorectal cancer, but associations were also seen for pancreatic cancer and prostate cancer.
Processed meat was classified as carcinogenic to humans (Group 1), based on sufficient evidence in humans that the consumption of processed meat causes colorectal cancer.
The experts concluded that each 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by 18%.
"For an individual, the risk of developing colorectal cancer because of their consumption of processed meat remains small, but this risk increases with the amount of meat consumed," says Dr Kurt Straif, Head of the IARC Monographs Programme. "In view of the large number of people who consume processed meat, the global impact on cancer incidence is of public health importance."
The IARC Working Group considered more than 800 studies that investigated associations of more than a dozen types of cancer with the consumption of red meat or processed meat in many countries and populations with diverse diets. The most influential evidence came from large prospective cohort studies conducted over the past 20 years.
For what it's worth a portion of 50 grams of processed meat is equivalent to two strips of bacon. Cancer Facts & Figures 2015 notes:
Incidence rates [for colorectal cancer] have been decreasing for most ofthe past two decades, which has been attributed to both changes in risk factors and the uptake of colorectal cancer screening among adults 50 years and older.
Earlier this year, the IARC classified the popular herbicide glyphosate as a probable (Group 2A) human carcinogen. The California EPA is going to list the herbicide as a probable carcinogen which requires that businesses with 10 or more employees that use chemicals on Calforinia's list must provide a "clear and reasonable warning" of the product's potential dangers. Will the Golden State now require steaks, chops, and burgers to have such labels?