Hot chips best worldwide meal for protecting biodiversity, study finds

When it comes to protecting the world's biodiversity, choosing what to eat makes a big impact.

So what meals are best?

A recent international studyhas ranked the biodiversity footprint of some of the world's favourite meals, and it's good news for those who like hot chips.

Using 151 of the most popular dishes on global recipe websites, the study analysed how much crops and livestock were putting the native environment at risk based on the combined ingredients.

The meal with the highest impact on biodiversity was Lechazo (roast lamb) from Spain, with the lowest being pommes frites, also known as French fries or hot chips.

Co-author of the University of Singapore study, associate professor Roman Carrasco, said similar analyses were typically done at the ingredient level, which was not what people think about when making meal choices.

To determine the rankings, the study compared the area's ingredients produced with the native fauna of that region.

"We overlay them and then we see actually the range of area this species can live that has been taken over by this crop," Dr Carrasco said.

"Then we rank dishes in terms of how many species are losing their home because we are eating that dish."

Hot chips, low impact

Dishes based on starches and potatoes were generally the most efficient, with beef-heavy meals largely the least.

South Australian spud farmer Terry Buckley – who farms near Mount Gambier – said it was not a big surprise to those in the industry that potatoes made for a low-impact snack.

"It is something we have always known. Yields are so high per hectare, which is what makes a difference," Mr Buckley said.

On his farm, Mr Buckley grows about 60 tonnes of potatoes per hectare of land.

"We are doing pretty well by world standards," he said.

"When you look at the water use, for what you get back, it is pretty impressive."

Only one Aussie dish was in the list, avocado on toast, which had the 58th largest footprint out of the 151 meals studied.

Location matters

Some of the worst offenders were meals from Brazil and India, countries which have retained high biodiversity but were facing increasing pressure from agriculture.

But a meat-free meal didn't always make for an ecological meal, with two vegan dishes from India placed in the top 10 as worst for biodiversity.

"The findings [showed] that vegan and vegetarian diets are more beneficial for biodiversity, but the caveat is that the location matters," Dr Carrasco said.

"For example, chickpeas are great if they are produced in a different place [than India], but if they are produced in a biodiversity hotspot, they are a very imperial species and can be as detrimental as eating meat."

Reducing your impact

Despite Australia not having meals high on the list, biodiversity expert associate professor Patrick O'Connor, from the University of Adelaide, said the nation's biodiversity was under threat.

"The big impacts are how we use land, water and the ocean; and agriculture is a big one of those," he said.

"As we become more able to clear other land or intensify the way that we use land, we'll have a bigger footprint."

For those looking to decrease their footprint, Professor O'Connor said some of the major differences consumers could make was to buy less meat, and buy locally.

"The basic rules for eating well and eating for a sustainable planet are to eat locally and eat things your great-grandmother would recognise as food," he said.

"That doesn't mean that you have to give up all animal proteins, but a consciousness of that makes a difference."