Processed Meats Do Cause Cancer — WHO

Red meat is a major source of iron, zinc and vitamin B12 (Image: AFP)

Processed meats - such as bacon, sausages and ham - do cause cancer, according to the World Health Organization (WHO). Its report said 50g of processed meat a day - less than two slices of bacon - increased the chance of developing colorectal cancer by 18%.

Meanwhile, it said red meats were "probably carcinogenic" but there was limited evidence.

But the WHO said meat did also have health benefits.

BBC reports that processed meat is meat that has been modified to increase its shelf-life or alter its taste - such as by smoking, curing or adding salt or preservatives.

It is these additions which could be increasing the risk of cancer.

WHO: Processed Meat Linked To Cancer; Red Meat Is Risky Too

Associated Press reports:

It's official: Ham, hot dogs and other processed meats can lead to colon, stomach and other cancers — and red meat is probably cancer-causing, too. While doctors in rich countries have long warned against eating too much meat, the World Health Organization's cancer agency gave the most definitive response yet Monday about its relation to cancer — and put processed meats in the same danger category as smoking or asbestos.

The findings don't say that a slice of salami is as dangerous as a cigarette, but they could weigh on public health policy and recommendations by medical groups amid a growing debate about how much meat is good for us. The meat industry protests the classification, arguing that cancer isn't caused by a specific food but also involves lifestyle and environmental factors.

A group of 22 scientists from the WHO's International Agency for Research on Cancer in Lyon, France evaluated more than 800 studies from several continents about meat and cancer. The studies looked at more than a dozen types of cancer in populations with diverse diets over the past 20 years.

Based on that evaluation, the IARC classified processed meat as "carcinogenic to humans," noting links in particular to colon cancer. It said red meat contains some important nutrients, but still labeled it "probably carcinogenic," with links to colon, prostate and pancreatic cancers.

Ian Johnson, a nutrition researcher with the Institute of Food Research who is unconnected to the IARC findings, cautioned that the classification doesn't reflect "the actual size of the risk," but said meat consumption is one of many factors contributing to high rates of bowel cancer in the U.S., western Europe and Australia.

"The mechanism is poorly understood, and the effect is much smaller than, for example, that of cigarette smoking on the risk of lung cancer," he said.

The cancer agency noted research by the Global Burden of Disease Project suggesting that 34,000 cancer deaths per year worldwide are linked to diets heavy in processed meat — compared with 1 million deaths a year linked to smoking, 600,000 a year to alcohol consumption and 200,000 a year to air pollution.

The agency said it did not have enough data to define how much processed meat is too dangerous, but said the risk grows with the amount consumed. Analysis of 10 of the studies suggested that a 50-gram portion of processed meat daily increases the risk of colorectal cancer over a lifetime by about 18 percent.

Doctors have warned that a diet loaded with red meat is linked to cancers, including those of the colon and pancreas. The American Cancer Society has long urged people to reduce consumption of red meat and processed meat.

"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," Dr. Kurt Straif of the IARC said in a statement. "In view of the large number of people who consume processed meat, the global impact on cancer incidence is of public health importance."

The North American Meat Institute argued in a statement that "cancer is a complex disease not caused by single foods" and stressed the importance of lifestyle and environmental factors.

The researchers defined processed meat as anything transformed to improve its flavor or to preserve it, including sausages, canned meat, beef jerky and anything smoked. They defined red meat as "all types of mammalian muscle meat, such as beef, veal, pork, lamb, mutton, horse and goat."
The report said grilling, pan-frying or other high-temperature methods of cooking red meat produce the highest amounts of chemicals suspected to cause cancer.