
The International Agency for Research on Cancer classified processed meats as carcinogens — cancer-causing agents.
You’ve probably seen the attention-grabbing headlines this week: Bacon causes cancer! But what’s the real story behind the news?
Earlier this week, the International Agency for Research on Cancer (IARC), the cancer arm of the World Health Organization, announced that it had classified processed meat as a carcinogen, or cancer-causing agent, “based on sufficient evidence in humans that the consumption of processed meat causes colorectal cancer.” It also classified red meat as a probable carcinogen based on limited evidence linking its consumption to cancer and “strong mechanistic support supporting a carcinogenic effect.”
In the report, a group of 22 experts from ten countries concluded that every 50-gram portion of processed meat eaten per day — the equivalent of a hot dog or two or three strips of bacon — increased the risk of colorectal cancer by 18 percent.
Experts from Memorial Sloan Kettering put this news into perspective.
“This announcement didn’t come as a big surprise to most of us,” says MSK gastroenterologist Robin Mendelsohn. “We’ve known for a long time that obesity is associated with cancer, so there’s a direct link between eating high-fat, high-calorie foods like meat and an increased cancer risk.”
Medical oncologist Clifford Hudis, Chief of MSK’s Breast Cancer Medicine Service, Vice President for Government Relations, and Chief Advocacy Officer, adds that foods high in preservative salts, such as processed meats, have been associated with gastrointestinal cancers for more than 100 years. He also notes that the refrigerator, by allowing us to eat things that use less of these specific salts, contributed to a decline in stomach cancer in the last century.

In addition, many processed meats like sausage and ham are smoked, which may further increase the number of carcinogenic compounds in them.
For other, nonprocessed red meat, the mechanism by which eating them may lead to cancer is not entirely clear, Dr. Mendelsohn says, but many of these foods also tend to be high in fat and calories.
Speaking about the IARC findings, Dr. Hudis explains, “an 18 percent increased risk is considered real but modest from a public-health standpoint, compared to cigarettes and tobacco, which increase the risk of lung cancer 800 percent or more. Some of the elevated risk may reflect the association of meat consumption with increased weight.”
“Given that much larger increases in risk are seen with tobacco as one example,” he says, “red meat is not the biggest issue. There are great reasons to avoid meat, including its high calorie content. The global issue we face is rising rates of obesity.” And like tobacco use, obesity is a modifiable risk factor for cancer, which means that people may be able to avoid increased risk by maintaining a healthy weight throughout their life.
“Obesity will soon replace tobacco as the leading modifiable risk factor for cancer, at least in Western countries, ” Dr. Hudis says, noting a policy statement issued by the American Society of Clinical Oncology earlier this year.
The bottom line: Experts agree that the most important thing to focus on is a healthy, balanced diet that includes lots of fruits and vegetables, as well as exercising regularly and keeping your weight under control. A diet low in meat can be an easy way to achieve this goal, says Dr. Hudis.
“Anytime you choose to eat something healthy, that’s better, but I like to eat a steak or a hot dog once in a while, and that’s OK. Everything in moderation,” says Dr. Mendelsohn.
Comments
Anonymous
Oct 30, 2015 • 6:33 PM
Memorial Sloan Kettering
Nov 3, 2015 • 11:57 AM
In reply to What time frame is "once in… by Anonymous
Thank you for your question. We forwarded it to Dr. Mendelsohn, who said that nobody really knows the answer to that question, but she noted that the WHO did point out that their report did NOT mean that meat and tobacco are equally dangerous. In addition, she says, meat, unlike tobacco, can provide nutritional benefit as a source of protein, iron, B12, and other nutrients.
Harsha
Nov 9, 2015 • 4:24 AM
Marios Tinis
Nov 18, 2015 • 6:54 PM
Memorial Sloan Kettering
Nov 19, 2015 • 12:31 PM
In reply to i have gleeson 6 prostate… by Marios Tinis
Marios, if you’d like to meet with a doctor at MSK, you can call 800-525-2225 or go to https://www.mskcc.org/experience/become-patient/appointment for more information on making an appointment. Thank you for your comment.
Anonymous
Nov 18, 2015 • 9:36 PM
Memorial Sloan Kettering
Nov 19, 2015 • 12:39 PM
In reply to Do nitrate free processed… by Anonymous
Y N
Mar 29, 2016 • 12:37 PM
Dear Y N, we are not able to offer specific medical advice on our blog. If you would like to make an appointment with one of our specialists, please call our Physician Referral Service at 800-225-2225. Thank you for reaching out to us.
Chakina Millin
Aug 22, 2018 • 1:45 PM
Will Vande
Nov 16, 2018 • 5:02 PM
David Lawrence
Nov 26, 2018 • 3:54 PM
I hear an awful lot of talk about the hazards of 'red meat' with religious zeal, much of which seems unthoughtful or at least unhelpful. There has never been a link established between myoglobin and negative health as chicken and turkey thighs contain more myoglobin than most pork. Cured meats aside, isn't the real issue with saturated to unsaturated fat ratios in the overall diet as well as fat consumption in general?
Todd
Feb 28, 2019 • 4:20 PM
Dear Todd, you may find this article from the National Cancer Institute helpful. Thank you for your comment.
What time frame is "once in a while"? I don't think it's safe to smoke a cigarette "once in a while", therefore.....