Americans' love affair with meat - we already knew - has some supersized impacts on the environment, from its intensive use of water to the enormous carbon footprint, as well as our nutritional health.
And today we learned more about its supersized impact on public health. Eating processed meats like bacon and hot dogs causes bowel cancer, while eating red meat (including beef and veal, pork, goat and lamb) probably is carcinogenic to humans. That's the conclusion of the World Health Organization's authoritative International Agency for Research on Cancer (IARC), which classifies red meat as a Group 2a carcinogen. The findings were published in the journal Lancet Oncology.
Processed meat was classified as Group 1, carcinogenic to humans - the strongest possible designation, like tobacco and asbestos. The classifications describe the strength of the scientific evidence, not the potency of the carcinogen. WHO's analysis estimates that for every 50 gram portion of processed meat eaten daily, the risk of bowel cancer rises by about 18%.
A Group 2a classification means there is strong evidence from studies in animals to label red meat as probably cancer-causing, combined with limited evidence from human studies that also shows eating red meat to be positively associated with developing bowel cancer in the colon or rectum. There also is science linking red meat consumption with prostate cancer and pancreatic cancer. Cancers of the colon and rectum are the 2nd most common cause of cancer-related deaths in American men and women, with nearly 50,000 deaths expected in 2015.
These are WHO's two highest cancer classifications. The risk rises with the amount of meat consumed. It would not be good medicine to wait longer before strongly advising the public to eat less red meat and especially less processed meat. WHO recommendations also include eating diets higher in whole grains and vegetables, in addition to limiting red and processed meats, because of evidence that dietary fiber protects against cancer.
Luckily, the WHO's ruling comes on the heels of a growing trend toward eating less and better meat in America. American red meat consumption has already dropped about 25% since the mid-1970's. But Americans on average still eat about 1.9 lbs of red meat per week - approaching double the E.U.-recommended amount of no more than about 500 grams (1.1 lbs) of cooked red meat per week.
Yet, if history is any guide, expect Big Meat to push back hard on the new IARC classification. It will likely try and raise doubt on the well-considered opinions of nutrition and health experts.
Happily, Big Meat doesn't represent the entire industry - so when people do eat red meat, they also can make better choices. An increasing share of the red meat consumed today is being met by producers of better meat - meat from well-stewarded farms and ranches, from animals raised more humanely and with no or reduced hormones and antibiotics.
How red meat is produced is a major health issue, for the animals of course, but also for people. Recent announcements by meat and restaurant companies, including Subway, underscore what the CDC, NRDC and others have long maintained - giving human antibiotics routinely to healthy animals has helped create a superbug problem. And that's a problem we can no longer ignore, or tolerate.
Companies like Panera and Chipotle are showing this approach to buying meat can be good not only for public health, but also for business. While sales of conventional meat are flat or declining, sales of healthier, more sustainably-produced meats are up.
And because meat products can be some of the most resource intensive to produce, eating less - and more sustainably raised - meat can reduce the impact of the conventional meat industry on our land, water, air and climate.
Bottom line: Eat less and better meat. Better for you, better for the planet. With Thanksgiving approaching, that's a change for which we could all be thankful.