THE morning news delivered a lot of shouty headlines about processed and red meat being linked to cancer by the World Health Organisation (WHO), but WHO’s finding isn’t straightforward.
After reviewing about 1000 research papers, the International Agency for Research on Cancer (IARC), a division of WHO, has decided that the evidence for processed meat being linked to cancer is in the same category as the links between asbestos, tobacco and alcohol and cancer.
Although “processed and red meat” tend to be lumped together in reporting on cancer, red meat comes in a category lower in WHO’s rankings of cancer-causing potential.
Red meat is “likely” to have some role in causing cancer, based on the evidence. It falls into the same category as shift work.
The question is,what do IARC’s rankings mean, if they mean anything at all?
Group 1, the group that processed meats have been placed into, is unequivocal. If something sits within this group, the evidence is strong that it has the potential to cause cancer.
That doesn’t translate to risk, though. IARC’s rankings are a measure of confidence on whether something causes cancer, not how much cancer it causes.
Cancer Research UK (CRUK’s) has a good explanation of the differences between hazard detection, which is what IARC does, and risk.
As CRUK’s carcinogen expert, Professor David Phillips, puts it, it is like banana skins. Slipping on a banana skin is a potential hazard, but in practice this doesn’t happen very often.
“And the sort of harm you can come to from slipping on a banana skin isn’t generally as severe as, say, being in a car accident,” Prof Phillips said.
“But under a hazard identification system like IARC’s, ‘banana skins’ and ‘cars’ would come under the same category – they both definitely do cause accidents.”
The Australian Dietary Guidelines in 2013 moved processed meats out of the basic food groups into the broad group of “discretionary foods” - foods that make no contribution to good health, and should be eaten only occasionally.
Not everyone agrees with IARC’s system. Federal Agriculture and Water Resources Minister Barnaby Joyce said it turned the issue into a “farce” to put processed meats like sausage and bacon in the same cancer-causing category as cigarettes.
“I don’t think we should get too excited that if you have a sausage you’re going to die of bowel cancer because you’re not,” Mr Joyce said.
“What obviously is part of this is you should have a balanced diet – too much of any one thing is bad for you and you certainly don’t want to live on sausages.
“The biggest thing is to make sure that you get a balanced diet but if you’re going to avoid everything that has any correlation with cancer whatsoever, don’t walk outside, don’t walk down the streets of Sydney; there’s going to be very little in life that you actually do in the end.”
Red meat is more complicated. IARC puts beef, lamb and pork in its Group 2A “probably causes cancer” category. Emissions from high-temperature frying and being a hairdresser or barber sit under the same category.
But while there is evidence that red meat has the potential to cause cancer, there is also ample evidence that it offers nutritional benefits - as a source of zinc, for instance.
The 2013 Australian Dietary Guidelines attempted to balance these contradictory health messages by suggesting that people limit red meat consumption to 450 grams per week - substantially less than the 700 g/w that Australian men now consume on average.
Despite the brief sensation of IARC’s findings, they reflect what health experts have been saying for years.
The bigger challenge for red meat sectors is that the IARC’s findings add to consumer impressions that red meat should be avoided.
In a global media environment, and in the indiscriminate world of social media, red meat has been subject to a constant trickle of negativity. It has been associated with deforestation, global warming, inhumane practices and poor health.
Consumption of red meat in the developed world has declined steadily over the decades, although the fall appears to have plateaued over the past few years.
The developing world is picking up on red meat consumption as consumers in developed economies are buying less, and for Australia in particular, that will be a stronger influence on red meat’s fortunes than domestic unease over health issues.
But consumers in developing economies are ultimately health-driven too.
In the long-term, red meat has to continue to make the case that it is a vital part of a healthy diet, and get people to pay accordingly.
MLA defends benefits of red meat
A spokesperson for Meat and Livestock Australia (MLA) said it is aware of the International Agency for Research on Cancer (IARC) evaluation of red meat and cancer.
"Promoting red meat as part of a healthy, balanced diet is important to the red meat industry and we are guided by the Australian Dietary Guidelines which recommend 455g/week of cooked red meat as part of a healthy, balanced diet," MLA says.
"The IARC report gives guidance that consumers should refer to the dietary guidelines in their own countries.
"Red meat such as beef and lamb is a critical, natural source of iron and zinc, vitamin B12 and omega-3 - essential nutrients needed to keep the body and brain functioning well.
"Children and women are eating less than the recommended amount of red meat and one in five women have some form of iron deficiency.
"There is no reason to believe that eating beef and lamb as part of a healthy, balanced diet and lifestyle in 100 to 200g portion sizes (raw weight), three to four times a week as recommended in the Australian Dietary Guidelines, will increase risk of cancer.
"When it comes to prevention of cancer and other chronic diseases such as heart disease and diabetes, the evidence suggests a healthy, balanced diet and active lifestyle is critical - focusing on only one kind of food is not enough.
Education around these issues is vital and MLA consults extensively with experts to ensure our nutrition communications are evidence-based and relevant to everyday Australians."
