Vegetarian diets may be better for the planet – but the Mediterranean diet is the one omnivores will actually adopt
What we eat and how we produce food are important. Food systems are responsible for more than a quarter global greenhouse gas emissions.
We cannot fully tackle the climate crisis without reducing the greenhouse footprint of our food. The issue is only becoming more urgent as world population grows alongside hunger resulting from the disruption of food exports by war. As people become wealthier and more urbanized, the global consumption of meat and dairy products is also increasing.
Livestock are the main source of our food emissions and the third highest global source emissions at 14.5%, after energy (35%) and transport (23%).
To reduce these emissions, many advocate switching to plant-rich or plant-only diets. But will people with a long-standing attachment to meat actually choose to change? Our new search suggests the sweet spot is the Mediterranean diet, which includes meat while remaining plant-rich and healthy.
What is the problem?
Raising livestock requires large areas of land, as well as water and feed inputs. More intensive livestock production is linked to loss of biodiversity, soil degradation, pollution of waterways, increased risk of zoonotic diseases such as COVID-19, and antibiotic resistance.
Although methods of reducing livestock emissions are in development, production is only half the story. To have a real impact, we also need to consider the demand side.
Without reducing overall demand for meat and dairy, livestock emissions are unlikely to decline fast enough or far enough. In wealthy countries like Australia, we consume meat and dairy products at high rates. Reducing these consumption rates could reduce greenhouse gas emissions and reduce other environmental damage.
So what diet should we eat? Obviously, any acceptable diet must be nutritionally adequate. While meat provides essential nutrients, too much is linked to disease like cancer. It is important to consider both the environmental and health qualities of a diet. We can also add to this animal welfare, which tends to be worse in Intensive livestock.
We hope that by identifying healthy and environmentally friendly diets with improved animal welfare, we can help people make sustainable food choices.
What did we find?
We looked at five common plant-rich diets and assessed their impacts on the environment (carbon footprint, land and water use), human health, and animal welfare. We focused on food production in high-income countries.
The plans we looked at were:
- Mediterranean (high in plants with small amounts of red meat, moderate amounts of poultry and fish)
- Flexitarian/semi-vegetarian (meat reduction)
- Pescatarian (fish, no other meat)
- Vegetarian (no meat but dairy and eggs OK)
- vegan (no animal products)
These five plant-rich diets all had less impact on the environment than the omnivorous diet, with meatless diets (vegans and vegetarians) having the least impact.
We must, however, add the caveat that the environmental footprint measures used to compare diets are simplistic and overlook important indirect effects of changing diets.
Overall, the Mediterranean diet was considered the healthiest for humans, while vegan and vegetarian diets had the best results for animal welfare. When we combined the three measures, vegan and vegetarian diets were found to be the most “sustainable” diets, based on reducing our food footprint, maintaining good health, and reducing negative impacts on animals. breeding.
We know which diets are the best. But which diet will people actually choose?
There is often a chasm between what we should be doing in an ideal world and what we are actually doing. To solve this problem, we looked at what people are actually ready to eat. Is promoting a vegan or vegetarian diet the most effective way to reduce the demand for meat and dairy products?
To find out, we asked 253 Australians what they were currently eating and which of five plant-rich diets they were willing to eat.
Australia is a very meat-consuming country, so it’s no surprise that most of our respondents (71%) identified themselves as omnivores.
Nor is it surprising that the diets least likely to be adopted are vegan and vegetarian diets, as these diets represented a major shift in most people’s eating habits.
As a result, the Mediterranean diet – which involves a slight reduction in meat consumption – had the highest likelihood of adoption. Combined with its high health benefits and moderate impacts on the environment and animal welfare, we have identified it as the best diet to promote.
Although some of these results may seem intuitive, we believe that by combining the social, environmental, human health and animal welfare elements of food consumption, we get a more complete picture for spotting pitfalls as well as solutions. realistic.
For example, it’s probably a waste of valuable time and resources to promote diets like the vegan diet that most people realistically aren’t willing to eat. Yet, despite people’s obvious lack of enthusiasm, most searches assessment of the environmental impact of different diets has favored vegan and vegetarian diets.
This is why it is important to have a broader vision. If we are serious about reducing meat and dairy consumption, we need to use approaches that have the best chance of working.
In high-income countries like Australia, this means we should promote the Mediterranean diet as the best diet to start meeting the demand for emission-intensive meat and dairy products. We need to start from a realistic point to start creating a more sustainable global food system.