Four days gone now and Thanksgiving officially kicked off the holiday season. For revelers of all backgrounds, this time of year has the potential to be one long party-fest from now through New Year’s. With this party atmosphere comes lots of bad food. Despite the season the Eagles are having, you can still bet there will be avid tailgaters grilling in the parking lot of Lincoln Financial Field before the remaining home games. And let’s not forget all the party platters full of cold cuts.
Most of us are quite aware that certain foods associated with celebratory events – hot dogs, pepperoni pizzas, “pigs in a blanket” – aren’t the heart-healthiest things to scarf down, especially in excess. At the holidays, that means preparing for the prospect of carrying a few extra pounds into the New Year. But most of us weren’t worrying about our favorite party foods causing cancer. Until now.
Last month, the World Health Organization (WHO) gathered an international panel of experts to respond to its International Agency for Research on Cancer (IARC) report on the dangers of the consumption of processed meats – those altered through salting, curing, fermentation, smoking and other processes to enhance flavor or improve preservation – and other red meats. The report classified processed meat as “human carcinogens,” IACR Group 1 – which places them in the same category as alcohol, asbestos and tobacco. The IARC also classified red meat – veal, beef, lamb, goat, pork, mutton, venison – as “probably carcinogenic to humans.”
For four days after the report was released and until the WHO finally published an online Q & A to talk folks down off a dietary ledge, the media terrorized salami-loving consumers across the globe with scary headlines like, "Processed meats pose same cancer risk as smoking and asbestos,” and “Processed meat ranks alongside smoking as major cause of cancer,”
“While I’m sure the strong headlines grab more readers, such media sensationalism is very misleading,” said Frederick A. Nunes, MD, section chief of the division of Gastroenterology at Pennsylvania Hospital (PAH), and a clinical professor of Medicine in Penn’s Perelman School of Medicine. “For decades now, we’ve known there was a link between some types of meats and some cancers, especially colorectal cancer. So this news isn’t exactly new. What is new is the growing evidence of the link, backed by good research.”
Nunes sees the recent hot pastrami hoopla as a result of taking things too literally. Classifying processed meat and possibly other red meat in the same category as tobacco and asbestos may have given some writers creative license to get, well, a bit too creative.
“The latest WHO report does not mean that processed meats are as dangerous as smoking. There is a big difference between evidence of causing cancer and the risk,” Nunes said. “We now have evidence – evidence as strong as the evidence of tobacco causing cancer – that processed meat also causes cancer. However, the risk of cancer from tobacco is much higher than that of processed and red meat.”
It’s also important to recognize the difference between absolute and relative risk for colorectal cancers. The IARC reports that in their assessment, the link between certain types of meat and certain types of cancer is real and established. However, it does not reflect how much cancer is caused by processed and red meat. The IARC researchers found that having a daily dose of processed meat – about the same amount found in one hot dog or 50 grams – can increase one’s relative risk of colorectal cancer by 18 percent. The American Cancer Society estimates that an average person’s lifetime risk of colorectal cancer is about five percent. That puts the potential lifetime risk of developing colorectal cancer at just under 6 percent even for a hearty hot dog eater.
Well then, what is it exactly that makes meat so dangerous? It’s all about chemicals. Part of the red pigment in blood in red meat, hemoglobin, gets broken down in the human gut from a group of chemicals called N-nitroso compounds. These compounds are known to cause cell damage in the lining of the intestines, and once that happens, other cells start replicating in an attempt to heal. The extra cell replication increases the chance of DNA cell damage – the first step toward cancer.
Close reading of the WHO report clarifies that red meat, or “muscle meat” such as veal, beef, pork and lamb, is probably carcinogenic, based upon limited evidence.
Where red meat gets us in trouble is in how it’s cooked. Brace yourself faithful BBQ/grilling masters: Cooking meat at high temperature and flame broiling it, where the fames actually touch the meat, creates chemical which may increase the risk of cancer. The report states there wasn’t enough data to support whether the manner in which meat is cooked affected cancer risk. “It’s probably not a good idea to eat meat that has been charred black,” Nunes said, “yet we don’t know if it is better to eat meat more raw, as that carries its own risks, like E.coli.”
Most nutritional and dietary studies like the WHO/IARC report have to rely on epidemiological – or “observational” – studies to show associations between consumption and cancer, Nunes said. “It should be taken into account that such studies are often contested as less rigorous than the randomized, experimental trials that are typically used for studying new drugs and devices. They are more about showing a link than direct cause or level of risk,” he said.
As director of the PAH Endoscopy Center, Nunes has spent much of his career focusing on cancer prevention and detection. He subscribes to the American Cancer Society’s most recent nutrition guidelines of consuming poultry, fish or lentils as alternatives to red and processed meat, and choosing lean cuts and smaller portion sizes for when you do indulge.
“It can be difficult for patients to work things out between what they want and what they should do for optimum health. We now know that a diet high in meat consumption over a long period of time is not a good idea,” Nunes said. “But a sausage or meatball sandwich a couple of days of week probably isn’t worth stressing too much over. In most cases, folks do not have to completely deprive themselves of foods they enjoy.”