Processed meats — like bacon and sausage — cause cancer, and red meat probably does, too, the World Health Organization announced Monday.
Here is a list of key questions and answers that you may want to know before your next meal.
What exactly qualifies as a processed meat?
Processed meat refers to meat that has been salted, cured, fermented, smoked, or undergone other processes to enhance flavor or to improve preservation, according to the WHO.
Most processed meats contain pork or beef, but processed meats can also contain other poultry, offal, meat byproducts such as blood, or other red meats.
Examples of processed meat include: Hot dogs, ham, sausage, corned beef, beef jerky, canned meat, and meat-based sauces and preparations.
What qualifies as red meat?
The WHO says that red meat refers to “all mammalian muscle meat,” including beef, veal, pork, lamb, mutton, horse, and goat.
What exactly did researchers find out about processed and red meat?
For processed meat, researchers found “sufficient” and “convincing” evidence that it causes cancer. The agency estimates that eating an average of 50 grams of processed meat daily increases the risk of cancer by about 18 percent.
For red meat, researchers are less sure of a possible link to cancer. Based on “limited evidence,” they found a “positive association” between eating red meat and developing colorectal cancer, but they are not entirely sure of a cause-and-effect relationship. If a red meat-cancer link were to be definitively established, the agency estimates, eating an average of 100 grams of red meat daily would increase the risk of cancer by about 17 percent.
If you eat more, the risk gets even higher, the agency said.
What type of cancers can eating these meats cause?
Researchers say that eating processed meat can cause colorectal cancer, and that they also suspect, but are less certain, that it could cause stomach cancer.
Eating red meat was associated with colorectal cancer and researchers say they also found links to pancreatic cancer and prostate cancer.
Is it as bad as smoking or other types of cancer-causing agents?
Technically, the WHO put processed meat in the same category as tobacco smoking and asbestos, but the agency stressed that “this does NOT mean that they are all equally dangerous.”
Have processed and red meat ever been blamed for causing cancer before?
The agency cited estimates from the Global Burden of Disease Project, an independent academic research organization, which has said that about 34,000 cancer deaths per year worldwide are attributable to diets high in processed meat, and 50,000 cancer deaths per year worldwide could be attributable to diets high in red meat.
By contrast, about 1 million cancer deaths per year globally are attributable to tobacco smoking, 600,000 per year are attributable to alcohol consumption, and more than 200,000 per year are seen due to air pollution.
Are some meats safer than others?
The agency said “there is not enough information to say whether higher or lower cancer risks are related to eating any particular type of red or processed meat.”
Are some people — women, men, children, elderly, women, men, people who already have cancer — more at risk?
The agency said it did not study whether the risks differ in different groups of people.
Does it matter how you cook the meat?
The agency said researchers had limited data about this and did not reach a conclusion about whether the way meat is cooked affects the risk of cancer.
What about eating chicken and fish?
The agency said it did not study the any possible links between eating poultry or fish and cancer.
What should I do? Stop eating meat? Go vegetarian?
The agency offered several recommendations:
The WHO says that limiting processed and red meat consumption may be beneficial, but it stopped short of telling people not to eat those types of meat at all. “Eating meat has known health benefits,” the agency noted.
At the same time, the agency said, “Many national health recommendations advise people to limit intake of processed meat and red meat, which are linked to increased risks of death from heart disease, diabetes, and other illnesses.”
Becoming vegetarian is not necessarily the solution to perfect health, according to the agency.
“Vegetarian diets and diets that include meat have different advantages and disadvantages for health,” the WHO said.