That Earth-shattering noise that you heard last week was the sound of a billion bacon-lovers, myself included, screaming out in agony after the World Health Organization (WHO) classified processed meats as a definite human carcinogen and also classified red meat as a probable human carcinogen. After newspapers proclaimed that eating bacon was as dangerous as smoking cigarettes — one such headline in the Guardian, a British newspaper, proclaimed that “Processed Meats Rank Alongside Smoking as Cancer Cause” — carnivores around the world were left wondering if they would need to give up their beloved meaty treats.
The answer is no. What the WHO’s International Agency for Research on Cancer — a group of 22 independent public health and cancer experts — found after reviewing 800 studies looking at environmental and lifestyle factors that contribute to cancer is this: eating 50 grams or more of processed meats like bacon or sausage daily raises an individual’s lifetime risk of colorectal cancer by 18%. Similarly, regularly eating 100 grams of red meat is associated with a 17% increase in risk. Based on these findings, the WHO classified these meats as group 1 carcinogens, the same cancer-causing category as tobacco.
This does not mean that eating bacon is as bad as smoking.
First of all, the International Agency for Research on Cancer classifies potential carcinogens into five categories based only on the weight of evidence that they are causally linked to cancer, not on the degree of cancer risk. Group 1 carcinogens like tobacco and asbestos are known to cause cancer. Group 2A and 2B carcinogens are probably or possibly linked to cancer, respectively. Group 3 compounds are not classifiable and group 4 materials are not carcinogenic. Bacon and other processed meats are now considered group 1 carcinogens; the nitrates and nitrites used to cure these meats turn into cancer-causing N-nitroso compounds in the gut. But there are lots of things that are also in that same category of cancer-causing agents, including alcohol, birth control pills, smog and (gasp) sunlight.
So when you sit out on your sunny patio on a lazy Sunday morning having a Bloody Mary and eating a bacon-and-cheese omelet, you are exposing yourself to all sorts of cancer-causing agents. But the likelihood that any one of these things will cause you to get cancer is slim. This is what all the fear mongering about bacon and red meat gets wrong: the risk of developing cancer from eating processed meat is much lower than the risk associated with smoking. Moreover, the relative risk of a bacon lover getting colorectal cancer doesn’t amount to much in terms of their absolute risk of developing the disease.
Colorectal cancer, to which eating bacon and other processed meats is now linked, is the third most common form of cancer in the US. According to the American Cancer Society, about 130,000 US residents will be diagnosed with colorectal cancer in 2015. About 50,000 will die of the disease. For the average American adult with no familial history of this disease, the lifetime risk of developing colorectal cancer is 1.8%; about 1-in-55 people will be diagnosed with this form of cancer. Eating two slices of bacon every day increases that lifetime risk to about 2.0%. By contrast, having a relative with colorectal cancer increases that risk to 3.4%, and having two or more relatives with a history of colorectal cancer increases it to 6.9%.
What about smoking and lung cancer? Lung cancer is the most common (and most preventable) form of cancer in the US. This year, about 225,000 Americans will be diagnosed with lung cancer and 160,000 will die of the disease. But rates of diagnosis vary widely between smokers and non-smokers. An adult male who smokes is 25 times (or 2500%) more likely to get lung cancer than a non-smoker. Tobacco smoke, it turns out, is 140 times more carcinogenic than bacon.
This isn’t to say that colorectal cancer is not something to be concerned about. It’s a serious and often deadly illness. Treatment can include chemotherapy, radiation, and even colostomy (removing the colon and creating an opening in the skin of the abdomen through which digestive waste drips out). However, there are ways of reducing your risk of developing or dying of this cancer without foregoing bacon or red meat. You can eat a diet that is also high in fiber and antioxidant-rich foods, you can exercise regularly, and you can get screened by colonoscopy starting at age 50 (or even earlier if you have familial history of the disease).
Of all the things in this world that are likely to kill us, bacon should be the least of our worries. Don’t let the media, the WHO, or your vegan friends try to convince you otherwise.
[This blog entry was originally presented as an oral commentary on Northeast Public Radio on November 4, 2015, and is available on the WAMC website.]