IARC TIED PROCESSED MEAT TO 18% HIGHER COLORECTAL RISK
The World Health Organization’s cancer agency ruled processed meat carcinogenic to humans, putting bacon, ham and hot dogs in Group 1.
The International Agency for Research on Cancer (IARC) announced the evaluations on October 26, 2015. It said there was sufficient evidence that eating processed meat causes colorectal cancer in humans. Red meat was classed as “probably carcinogenic to humans.”
The American Institute for Cancer Research (AICR) said it “strongly supports” the report. The group hoped it would spread awareness that diet plays a role in cancer risk.
“For years AICR has been recommending that individuals reduce the amount of beef, pork, lamb and other red meats in their diets and avoid processed meats like bacon, sausage and hot dogs,” said Susan Higginbotham, RD, PhD, AICR’s vice-president of research.
“This advice grows out of our expert reports and the Continuous Update Project, our ongoing review and analysis of the global scientific research on how diet, physical activity, and weight affect cancer risk,” she said.
The key number
The figure came from IARC’s own announcement. Each 50-gram portion of processed meat eaten daily was associated with an 18% increase in colorectal-cancer risk.
IARC also reported an association between processed meat and stomach cancer. For red meat, it said the link was seen mainly for colorectal cancer. Associations were also observed for pancreatic and prostate cancers.
The agency described the red-meat evidence as limited in humans. It paired that with strong mechanistic evidence supporting a carcinogenic effect.
AICR’s article listed hot dogs, bacon, ham, sausage and cold cuts as processed meats. It gave beef, pork and lamb as examples of red meat.
What the label does and doesn’t mean
The classifications have a catch. IARC’s categories reflect how strong the evidence is that something can cause cancer. They do not measure the size of the risk.
AICR pointed to CDC information that cigarette smoking can multiply a person’s cancer risk by as much as 20 times. The group stressed that the processed-meat classification does not mean the two pose equal levels of risk.
AICR said its own analyses found regular consumption of even small amounts of processed meat was associated with increased colorectal-cancer risk. It added that some studies found people eating diets high in processed meat had nearly double the colorectal-cancer risk of non-meat-eaters.
Moderate red-meat consumption was a different story, AICR said. Its analyses found no notable increase in colorectal-cancer risk at that level.
AICR recommended avoiding processed meat. It said people should eat no more than 18 ounces of cooked red meat a week to lower colorectal-cancer risk.
What happened next
Three days after the announcement, the WHO issued a clarification. Hong Kong’s Centre for Food Safety reported that the October 29, 2015 statement said WHO’s earlier advice to moderate consumption of preserved meat to reduce cancer risk still stood.
AICR’s current recommendation page still tells people who eat red meat to limit it.
