The world's biggest ever survey on climate change shows that people are thinking green, just not when it comes to their dinner plates.

The People's Climate Vote, conducted by the United Nations Development Programme (UNDP) with the help of the University of Oxford, polled 1.2 million respondents in 50 countries. The study, published Wednesday, aimed to "connect people to policymakers" by further involving the public in the global debate about climate crisis and seeking their opinions about what steps they think their governments should be taking in response.

Eco-conscious global public

Almost two-thirds (64 percent) of those surveyed said that they considered climate change a global emergency. Among them, over half (59 percent) believed that the world must "do everything necessary and urgently" to tackle the crisis.

Respondents were asked to pick possible climate actions that they supported from a list of 18 policies across six areas – energy, economy, transportation, farms and food, protecting people and nature. Forest conservation (54 percent) and investment in renewable energy (53 percent) proved to be the most popular worldwide, although a deep dive into the findings shows that policy priorities were associated with the circumstances of different countries. 

For example, there was strong backing for clean transport systems in countries with sizeable urban populations like Japan and Chile. In eight of the top 10 emitters surveyed, such as the United States and Germany, residents showed considerable support for renewable energy. And in Brazil and Argentina, places with widespread deforestation, there were majority calls for ecological conservation.

No appetite for greens

But one impactful fix to climate change seems to be out of favor. Promoting plant-based diets ranked the lowest of all 18 policies, with just 30 percent of people surveyed endorsing the move.

The lukewarm support for an eco-friendly diet comes as food choices are increasingly under scrutiny for their impact on the climate crisis.

Traditional livestock farming has long been criticized for its contribution to environmental degradation through razing forests for pasture and contributing to greenhouse gas emissions. But the problem goes beyond belching cows to include all the activities that orbit the culinary universe.

The food system – what we eat, how we grow it and get our hands on it and what ends up in the trash bin – is responsible for a third of all global greenhouse gas emissions, according to Eduardo Calvo Buendia, co-chair of the Intergovernmental Panel on Climate Change (IPCC), a UN body. In 2019, a report by the IPCC on the relationship between land use and climate change called for an overhaul to dietary habits to save the planet and ease the strain on natural resources.

The 107 scientists who prepared the report agreed that a shift to plant-based foods, as well as sustainably sourced meat, is a major opportunity to tackle climate change, but didn't go as far as calling for everyone to adopt a vegetarian or vegan diet.

Read more: UN report: Eat less meat and you'll help save the planet

"We don't want to tell people what to eat," Hans-Otto Portner with the IPCC said at the time. "But it would indeed be beneficial, for both climate and human health, if people in many rich countries consumed less meat."

Not an easy shift

From Shanghai to Seattle, consumers are becoming more mindful of what ends up on their plate, with many cutting back on their meat intake amid an explosive growth in alternatives almost indistinguishable from the real deal.

So why is this lack of enthusiasm among respondents to more greens at the dining table?

"First, in some countries, there are few plant-based options. In others, there may not yet be significant awareness about these options. In others, people may have felt that diet is more of a personal choice than something that can be 'promoted'," UNDP researchers wrote.

"The low scores do not signify that people are against the policies, since not endorsing a policy could also be due to indifference to it," they noted, adding, "This could be an important opportunity for further education on these topics."

The authors' emphasis on expanding awareness echoes the findings of a 2020 study by Yale University that looked at the perception of plant-forward diets among Americans. Researchers found that about half of the respondents (51 percent) expressed willingness to give plant-based options a go if "they had more information about the environmental impact of different products and/or foods."

Read more: Mock pork dumplings might just warm China to meat substitutes

Increased knowledge can help shoppers add more veggies, fruit and legumes to their carts, but food choices are a complex issue where culture, habit, personal taste, budget and emotions interact with each other at the grocery store and in the kitchen.

A meta-analysis of 101 literature sources done by a team of Hungarian and Polish researchers last year examined the benefits and hurdles of converting to an all-plant diet, and found that when it comes to giving up meat, old habits die hard.

"The enjoyment of eating meat and the immense difficulty in giving it up are suggested by surveys to be the biggest barriers to the switch to a plant-based diet," the authors said.

Perhaps one day some of the public's demonstrated appetite for policy action to tackle climate change would be reflected in their meals.