For bacon lovers, the news that the World Health Organization has linked red and processed meats to cancer may sound like the coming of the aporkalypse. But a closer look at the dangers posed by red meat suggests that cancer may be the least of carnivores’ worries.
The report classifies processed meats like bacon, sausage, hot dogs and beef jerky as Class 1 carcinogens, meaning that the study found “convincing evidence” that they can cause cancer. This classification is reserved for items and behaviors with the strongest links to cancer, such as tobacco smoke and UV radiation.
Red meats, including beef, veal, pork, lamb, mutton, horse, and goat, were classified as possibly causing cancer—an indication of slightly lower hazard.
These conclusions sound pretty terrifying. But nutrition researcher Ian Johnson, who works at the Institute of Food Research in the United Kingdom, says it’s important to remember that these classifications don’t show how much a given substance or behavior increases the risk of cancer. Instead, they indicate how certain the agency is that it could lead to cancer. Just because hot dogs are now in the same category as cigarettes doesn’t mean they’re both equally bad for you, as some headlines have suggested.
The WHO notes that eating 50 grams, or 1.75 ounces, of processed meat a day “increases the risk of colorectal cancer by about 18%.” For comparison, smoking a pack of cigarettes each day increases a person’s risk of developing lung cancer by about 2400%, according to a 2005 study in the British Journal of Cancer.
“The effect of red meat is surprisingly weak, far weaker than the effects of tobacco,” Johnson said.
In the UK, people have a 5% risk of being diagnosed with colon or bowel cancer during their lifetimes. Assuming they ate 50 grams of bacon each and every day of their lives, a back-of-the-envelope estimate suggests that their lifetime risk of these cancers would rise to 6%. That’s an increase, to be sure. But it’s going a little too far to suggest that Porky the Pig is going to kill us all.
That said, cancer risk is just one of several good reasons to reduce consumption of red meat. There are other ways that that a steady diet of cheeseburgers and spare ribs can be dangerous to your health and to the planet.
Americans have been advised for decades to wean themselves off red meat. It’s high in saturated fats, which have been linked to heart disease and high cholesterol in a variety of studies, including a 2012 study published in JAMA Internal Medicine. The same study also found that people who regularly ate even small amounts of red meat had a slightly increased risk of premature death. In the newest set of recommendations to update US dietary guidelines, Americans were advised to eat less processed red meat in order to reduce the risk of heart disease as well as other illnesses such as diabetes and obesity.
Eric Hargis, CEO of the Colon Cancer Alliance, notes that a large portion of colon cancer cases are preventable with regular screenings, whereas preventing heart disease is much more difficult. So cutting back on red meat consumption to ward off heart disease may be an even better motivator than doing so to reduce the risk of colon cancer.
Red meat also poses dangers to the environment, since raising livestock is an energy-intensive, potentially ecologically destructive practice. A 2014 study in the Proceedings of the National Academy of Sciences shows that livestock production causes one-fifth of worldwide greenhouse gas emissions and is a major source of land and water pollution. Such environmental hazards may be magnified as the rising middle class in developing countries such as China begin to eat more meat, as documented in a 2015 study in the European Journal of Clinical Nutrition. So transitioning to a more plant-based diet can also help feed the world without destroying the planet.
The upshot of all this news is that eating less red meat may not dramatically affect your risk of developing cancer. But laying off the salami is still probably the right move.