Does Bacon Cause Cancer?
When you take a food that billions of people eat regularly and deem it a carcinogen, you’re going to set off a panic. So it’s not surprising that when the World Health Organization announced that processed meats cause cancer—and that red meats probably cause cancer—we wound up with headlines like “Bacon & Hot Dogs Are Just as Dangerous as Cigarettes.”
But before you break up with bacon, here’s what you need to know.
We’re talking about a minuscule risk
If meat does cause cancer (more on that later), the risk for any one person is tiny. How tiny? One key study cited by the WHO panel found that people who ate the least processed and red meat—less than 10 grams per day—had a 1.28 percent chance of developing colorectal cancer over the course of 10 years. People who ate the most—more than 160 grams, which is the equivalent of eating three hot dogs or 5.6 ounces of steak every single day—had a 1.71 percent chance of getting colorectal cancer.
We’re talking about a difference of less than half a percent. Put another way, for every 1000 people who eat the least amount of these meats, about 12 will get cancer. For every 1000 who eat the most, about 17 will develop the disease.
This pales in comparison to the risk posed by cigarettes, says Robert Turesky, Ph.D., a biochemical toxicologist at the University of Minnesota and a member of the WHO panel.
Still, that doesn’t mean it’s not important, says Theresa Norat, Ph.D., a coauthor of the study that assessed risk. Because anyone who’s ever gotten colorectal cancer will probably tell you: Do whatever you can to avoid it.
The science isn’t definitive, anyway
The WHO panel wasn’t unanimous in its decision to deem meats carcinogenic. The report even concedes that the research is mixed: 12 of 18 studies identified a link between processed meat and cancer, and seven of 15 studies found a connection between red meat and cancer.
Men’s Health nutrition advisors Michael Roussell, Ph.D., and Alan Aragon, M.S., are both skeptical. Red meat may just be guilty by association, they say. “It is very difficult to separate red meat intake from other adverse lifestyle habits that contribute to disease,” says Aragon.
People who eat lots of red and processed meat tend to also have unhealthy habits, Roussell says. They’re more likely to smoke, be sedentary, be overweight, and eat less fruits and vegetables. Sure, researchers try to adjust for those factors.
“But I genuinely question how well this works,” says Roussell. “If you are a fat, sedentary, overeating person, can we really ‘control’ for those other factors and extract just the effect of the pepperoni on your pizza on your cancer risk?”
Plus, the definition of “red meat” is so broad that it’s hard to isolate what foods could really be guilty, says Roussell. Pork ribs and beef sirloin are grouped into the same category, but they’re very different foods.
It doesn’t mean meat is bad for you
Not even the WHO panel is saying that you should give up meat. It’s one of the most nutrient-dense foods that exists, providing high-quality protein, iron, zinc, and vitamins B6 and B12, according to a paper by panel member David Klurfeld, Ph.D., a scientist for the U.S. Department of Agriculture.
Researchers still don’t know what it is about red and processed meats that could be causing cancer. The theory for red meat is that charring it produces carcinogenic chemicals—but that’s unconfirmed, says Turesky. (And even if it is the culprit, the same chemicals can result from charring chicken, fish, and vegetables marinated in oil, Roussell says.)
As for processed meat—which includes hot dogs, sausage, smoked deli meats (even turkey), jerky, and bacon—it seems that something about the preservation process results in harmful chemicals, Turesky says. Some research has identified nitrates and nitrites as possible scapegoats. But there’s no proof yet that nitrate- and nitrite-free products are safer, he says.
This changes nothing
All the WHO report does is re-emphasize what we already knew, says Turesky: Meat has important health benefits, but should be consumed in moderation as part of a balanced, diverse diet. Want to minimize your already-minimal risk? Trim the charred parts off your steaks, says Aragon. And don’t eat processed meats more than a few times per week.
But the oldest advice in the book still stands: “I choose to keep everything in moderation, including moderation, since you can meet your death any number of ways in this life,” says Aragon.