Still, nobody believes that eating cheese leads to bed death.

Yet the same logic is being used to assume a casual relationship between red meat and cancer, and not just by the makers of alternative meats or anti-livestock activists but by scientists.

This is just one example - albeit a rather unfathomable one - of how lacking in evidence the anti-meat narrative has become that was put forward by United States registered dietitian and nutritionist Diana Rodgers at an Australian conference this week.

Ms Rodgers, who co-authored the renowned book Sacred Cow, was a guest speaker at the 2022 Resource Consulting Services Conference held in Brisbane.

She said meat was increasingly being charged as unhealthy, unsustainable, unnecessary and unethical and her work was about pushing back on all this because none of it was evidence-based and it was doing harm to the health of people around the world.

The claims of links between red meat and cancer were among the most widespread examples of misinformation on the issue, Ms Rodgers said.

"All the research touted as showing meat is unhealthy is largely observational studies, not experimental research, and they use self-reported data," she said.

The results also show correlations, rather than causation.

"Just because one thing is associated with something else, doesn't mean it causes that something else," Ms Rodgers said.

Shifting the anti-meat narrative had become like a game of whack-a-mole, Ms Rodgers said.

"The minute you try to explain that meat is a nutrient dense food and there has never been any science to show meat causes heart disease or cancer, the goal posts shift to the argument cattle take up too much land," she said.

"So you explain cattle are grazing on land that mostly can not be cropped and then it is 'well they emit greenhouse gases."

After the facts about emissions are spelt out, the argument moves onto 'it's just wrong to kill beautiful animals,' Ms Rodgers said.

"We need to stop comparing land to calories, instead it should be resources to nutrients. Cattle and sheep are net protein 'upcyclers'- that is they transform food we can't eat that is growing on land we can't crop into the most nutrient-dense food available for humans."

Ms Rodgers said of enormous concern was the motivations behind the corporations that stand to make a lot of money by pushing the anti-meat agenda.

"That meat is bad is a convenient narrative for the fossil fuel, pharmaceutical and alternative protein companies and they have a ready-made guerilla-style marketing force in people who truly believe that these products are more sustainable and more ethical."

Eliminating meat would do more harm than good, Ms Rodgers believes.

She pointed to a National Academy of Sciences 2017 study that found if the entire of the US eliminated all animal-sourced food, GHG emissions would be reduced by just 2.6 per cent.

"At the same time, overall calories and carbohydrate intake would increase, which is not good in a population where 70 per cent of people are already obese," she said.

IN OTHER NEWS:

The study found the decreased intake of nutritious animal-sourced foods would lead to nutrient deficiencies, particularly calcium, vitamins B12 and A and essential fatty acids.

Animal-sourced foods like milk, meat and eggs were top sources of commonly lacking nutrients like vitamin B12, iron and zinc, Ms Rodgers said.

"By far, they are the most important in the human food system."