World Health Organization links processed and red meat to risk of cancer
Love those hot dogs when visiting your favorite ballpark? Or how about bacon which is available on just about everything today from toppings on what should be a healthy salad to even ice cream? Not to mention those yummy, juicy burgers grilled outdoors in the summer?
We eat them even though we’ve heard before that they are not good for us on a regular basis.
Now, the International Agency for Research on Cancer (IARC), the cancer agency of the World Health Organization (WHO), has determined that the consumption of processed meats like hotdogs, ham, sausages and meat-based sauces causes colorectal cancer, while eating red meat like beef, pork and lamb is “probably carcinogenic to humans.”
After thoroughly reviewing the accumulated scientific literature, a working group of 22 experts from 10 countries, convened by the IARC Monographs Programme, classified the consumption of red meat as “probably carcinogenic to humans.” Their findings were based on limited evidence that the consumption of red meat causes cancer in humans.
This association was observed mainly for colorectal cancer, but associations were also seen for pancreatic cancer and prostate cancer.
Processed meat was classified as “carcinogenic to humans,” based on “sufficient evidence” in humans that the consumption of processed meat causes colorectal cancer.
The consumption of meat varies greatly between countries, with from a few percent up to 100% of people eating red meat, depending on the country, and somewhat lower proportions eating processed meat. Experts concluded that each 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by 18%.
“For an individual, the risk of developing colorectal cancer because of their consumption of processed meat remains small, but this risk increases with the amount of meat consumed,” says Dr. Kurt Straif, head of the IARC Monographs Programme. “In view of the large number of people who consume processed meat, the global impact on cancer incidence is of public health importance.”
Dr. Wilson Mertens, vice president and medical director, Cancer Services at Baystate Health, noted it is important to put the risk in perspective.
“Eating two slices of processed meat daily increases the risk of cancer by a factor of 1.2, while tobacco use increases the risk of lung cancer by 15- to 25-fold, and is significantly associated with a variety of other cancers and adverse health effects. While the WHO attributes approximately 34,000 deaths annually worldwide due to cancer caused by processed meats, this is in the context of over 8 million cancer deaths of all types globally,” said Dr. Mertens.
The IARC Working Group considered more than 800 studies that investigated associations of more than a dozen types of cancer with the consumption of red meat or processed meat in many countries and populations with diverse diets. The most influential evidence came from large prospective cohort studies conducted over the past 20 years.
”These findings further support current public health recommendations to limit intake of meat,” says Dr. Christopher Wild, director of IARC. “At the same time, red meat has nutritional value. Therefore, these results are important in enabling governments and international regulatory agencies to conduct risk assessments, in order to balance the risks and benefits of eating red meat and processed meat and to provide the best possible dietary recommendations.
According to Dr. Mertens, if the goal is improved cancer control and reduced cancer-associated mortality, the biggest impacts can be expected from the reduction or elimination of tobacco use. In addition, moderation in alcohol consumption, avoidance of obesity, exercise, consuming a balanced diet that increases the daily amount of fresh fruits and vegetables, and participating in effective cancer screening programs, particularly for colorectal cervical, lung and breast cancer as appropriate for one’s age, gender and risk profile are all important.
“Reducing processed and red meat consumption could make a real, but comparatively small, contribution to reducing the burden of cancer in our society,” he said.
Baystate Medical Center registered dietitians Sheila Sullivan and Paula Serafino-Cross weigh in on WHO’s announcement:
“Our message in Food and Nutrition Services has always been consistent. The Mediterranean Diet stresses variety and moderation. Red meat should be limited to 4 oz. per week. Red meat is a good source of nutrients such as vitamin B12, B6, niacin and zinc and protein. Chicken and fish are a good source of protein and B vitamins, although not as rich a source of iron and zinc. Patients have always been told to limit or avoid processed meats such as hot dogs, sausage and bacon. Most people’s protein needs are easily met without having red meat in their diet. Remember, a variety of fruits, vegetables, whole grains, beans and low fat dairy along with chicken and fish will provide plenty of protein and nutrients. If you are still concerned about getting enough iron or zinc, ask your registered dietitian if you should be taking a multivitamin with minerals."