
In a report released Nov. 5, 11,000 scientists from around the globe signed a Climate Emergency Declaration imploring governments, policymakers and consumers to take serious and urgent action to reduce emissions, especially in “the most affluent countries [that] are mainly responsible for the historical GHG emissions and generally have the greatest per capita emissions.”
The scientists outline “six critical and interrelated steps that governments, businesses, and the rest of humanity can take to lessen the worst effects of climate change,” including:
“Eating mostly plant-based foods while reducing the global consumption of animal products, especially ruminant livestock, can improve human health and significantly lower GHG emissions. Moreover, this will free up croplands for growing much-needed human plant food instead of livestock feed, while releasing some grazing land to support natural climate solutions. Cropping practices such as minimum tillage that increase soil carbon are vitally important. We need to drastically reduce the enormous amount of food waste around the world.”
Surging Scientific Consensus
The Climate Emergency Declaration marks the latest in a seemingly endless stream of scientific studies, reports and campaigns urging an immediate shift to more plant-based diets as a crucial step in avoiding or mitigating the worst impacts of climate change.

In the last few years, more and more scientists— from climate and environmental scientists to land use researchers, wildlife experts, and food security scholars— have concluded that even the most “sustainable” forms of meat & dairy production are massively inefficient, polluting, ecologically destructive, and unconscionably wasteful of our shared natural resources. (This, in addition to the fact that humans have no biological need to consume animal products).
In a 2018 Oxford University study hailed as “the most comprehensive analysis to date” of the environmental impacts of different forms of farming, the researchers concluded, “Avoiding meat and dairy products is the single biggest way to reduce your environmental impact on the planet.”
As reported in The Guardian: “The research shows that without meat and dairy consumption, global farmland use could be reduced by more than 75% – an area equivalent to the US, China, European Union and Australia combined – and still feed the world. Loss of wild areas to agriculture is the leading cause of the current mass extinction of wildlife.
The new analysis shows that while meat and dairy provide just 18% of calories and 37% of protein, it uses the vast majority – 83% – of farmland and produces 60% of agriculture’s greenhouse gas emissions. Other recent research shows 86% of all land mammals are now livestock or humans. The scientists also found that even the very lowest impact meat and dairy products still cause much more environmental harm than the least sustainable vegetable and cereal growing.
The study… created a huge dataset based on almost 40,000 farms in 119 countries and covering 40 food products that represent 90% of all that is eaten. It assessed the full impact of these foods, from farm to fork, on land use, climate change emissions, freshwater use and water pollution (eutrophication) and air pollution (acidification).
Joseph Poore, lead researcher of the study, told the Guardian, “The reason I started this project was to understand if there were sustainable animal producers out there. But I have stopped consuming animal products over the last four years of this project. A vegan diet is probably the single biggest way to reduce your impact on planet Earth, not just greenhouse gases, but global acidification, eutrophication, land use and water use… Avoiding consumption of animal products delivers far better environmental benefits than trying to purchase sustainable meat and dairy.”
That message is also echoed by the World Resources Institute, which notes, “Even the most efficiently produced beef is going to be a lot more impactful from a land use or greenhouse gas perspective than the least efficient plant-based protein.”
Learn more about why even local, organic and grass-fed/pastured animal products are inefficient, resource intensive, and bad for the environment. And check out our collection of powerful quotes and statistics from many other experts urging plant-based diets for the climate and environment.