Meat-free: what would happen if everyone went vegan or vegetarian?

In a world where our natural resources are diminishing, but the population is fast increasing, it makes sense to think about the effect our food choices are having on the planet.

While vegetarianism and veganism are getting some serious traction, the desire for red meat is also on the up globally – particularly in developing countries such as China, as growing incomes lead to more choice at the dinner table.

According to the Food and Agriculture Organization of the United Nations, worldwide demand for livestock products is projected to increase by 70% to feed an estimated population of 9.6 billion by 2050.

Many Australians are eating too much meat

In Australia, we’re already a nation of meat lovers. The average Aussie eats 95kg of meat each year, well above the OECD average of 69kg, says Dr Michalis Hadjikakou, a research fellow with Deakin’s School of Life and Environmental Sciences.

That fondness for meat contributes to us being a nation with one of the largest per capita environmental footprints in the world.

So perhaps it’s worth posing the question: do we really need meat? And hypothetically, if everyone decided to become vegan or vegetarian, how would that affect not only our diets, but the environment too?

It’s a complex question with many variables, including whether animals are pasture-raised or grain-fed, Dr Hadjikakou says.

‘Major source of greenhouse gas emissions’

Dr Hadjikakou says that ‘ruminants’ – mammals including cows, goats and sheep– emit extremely high levels of methane because of the way they digest their food. ‘This is a major, major source of greenhouse gas emissions. Globally we’re talking around 14 to 15 per cent of all emissions.’

Of course food production also has a massive impact through the use of water, fertiliser, and the effect on landscapes and biodiversity.

‘The reason why meat is a problem is mainly C02 emissions and also the fact that increasingly animals are not free range; they are confined. They rely on large amounts of feed and that feed has impact in this production,’ Dr Hadjikakou says.

Health impacts

Dr Hadjikakou says there is clear evidence that eating too much red meat can put you at higher risk of developing cardiovascular problems, or even cancer. Many Australian adult males are eating significantly above the recommended amount.

However at a global level, Dr Hadjikakou says there are still many people in the developing world that suffer from protein deficiencies and would benefit from additional protein, such as meat or dairy, in their diet.

Meanwhile, Dr Hadjikakou says the science on the health benefits of going vegan is unclear.

‘I think most dietary guidelines, they’re OK with vegetarianism, but they do not currently endorse veganism in terms of getting all the nutrients you need. My understanding is that vegan diets can be nutritionally complete but require more diligence to ensure micronutrient needs are fully met.’

Other options to going vegan or vegetarian

Perhaps a more realistic option for most people is the concept of ‘flexitarianism,’ where you reduce, rather than cut out, your meat intake, Dr Hadjikakou says.

However he also suggests experimenting with alternative sources of animal protein, such as kangaroo or feral goat, along with vegetable proteins such as nuts and legumes.

Environmental benefits of giving up meat                              

As for going totally meat-free, there are some obvious environmental benefits, but it’s complicated.

‘I can tell you that greenhouse gas emissions would be significantly lower – there’s no doubt about that – but there’s some concerns with respect to other indicators, like water especially, because a lot of plant foods are actually quite high in water requirements, especially here in Australia. They’re often higher than (pasture-raised) meat,’ Dr Hadjikakou says.

‘But if we are talking about meat that is raised on grains (as is the case in many other parts of the world other than Australia), then its footprint is almost always higher compared to plant products because there’s all those plant products that go to feeding that animal.’

The complexities of land use

The use of land is also not as clear-cut as you might think.

‘Not all land is the same, so using up one type of land doesn’t necessarily mean you could have grown crops on it.’

Interestingly, research has shown that zero livestock might not be the best system for the environment, Dr Hadjikakou says.

‘One of the reasons is because a lot of animals are able to use marginal land that’s not suitable for crop production. And they’re also able to recycle roughage and plant material in a way that if done efficiently, is actually beneficial and produces nutrients that enhance our diets.

‘Would the planet benefit from a significant reduction in meat consumption? Yes, absolutely. But whether zero livestock production would actually be beneficial to the planet, that’s not clear to me.’

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