Meat's Environmental Impact
From greenhouse gas emissions and deforestation to water use and pollution, meat production plays a significant role in the planet’s changing climate.
Is eating meat bad for the environment?
- Livestock production accounts for 14-18 percent of global greenhouse gas emissions, including 32 percent of methane gas emissions worldwide.
- More than two-thirds of all agricultural land is devoted to growing feed for livestock, while only 8 percent is used to grow food for direct human consumption.
While the global meat industry provides food and livelihoods for billions of people, research shows it also has significant consequences for the planet. From greenhouse gas emissions and deforestation to water use and pollution, meat production plays a significant role in the planet’s changing climate. Worldwide consumption of pork, beef, poultry and other livestock is projected to reach over 500 million tonnes by 2050 – double what it was in 2000. As demand continues to rise, Stanford researchers are studying how meat production affects the environment and identifying sustainable solutions to reduce its impact.
This page brings together the latest research from Stanford scholars to explain how meat production affects the climate, land, water, and biodiversity. It’s meant to help readers quickly understand the science behind one of the largest drivers of land use and agricultural emissions.
Frequently asked questions
Q: How much land is used for livestock production?
A: Globally, agriculture occupies about half of the world’s habitable land, and nearly 80 percent of that farmland is devoted to livestock.
Large areas of pasture and feed cropland replace native ecosystems that would otherwise store carbon. Transitioning that land back to natural vegetation could unlock massive carbon gains through biomass recovery. Stanford modeling shows that restoring native ecosystems on former livestock land could sequester up to 800 gigatons of CO₂ over several decades — while simultaneously reducing methane and nitrous oxide emissions from livestock. Together, these changes could freeze the growth of global warming potential for ~30 years and deliver emissions reductions equivalent to 68 percent of today’s global CO₂ output.
Explore the research.
Q: What types of meat have the most environmental impact?
A: Beef and other ruminant meats (like lamb, goat, and buffalo) have the largest environmental footprint. Ruminants are a type of animal with a four-chambered digestive system that allows them to digest tough, fibrous plants such as grasses, producing methane as a byproduct.
A recent inventory of livestock emissions shows that ruminants account for about 80 percent of livestock methane – a powerful greenhouse gas – even though they’re just one slice of the world’s diet. Pigs and chickens contribute much less methane, and life-cycle studies show they also use 8–10 times less land per gram of protein than beef. That means shifting even part of our diets away from beef and lamb toward lower-impact meats or plant-based proteins can free up land and significantly cut warming pollution.
Explore the research
Latest news
A Stanford food and agriculture expert discusses a record-setting slab of lab-grown meat – and what it means for the future of food.
Stanford researchers are studying how changing weather patterns, rising temperatures, and ecological shifts affect the global food system, while developing ways to improve food security for all.
Dozens of faculty members at Stanford are working to transform the way the world grows, distributes, and consumes food, with research and scholarship spanning topics including sustainable food systems, food security, health equity, culture, and diet.
Latest videos
Ellen Kuhl, professor of mechanical engineering, on the mechanical signature of plant-based meat.
Related scholars
Rosamond Naylor
Naylor's research focuses on policies and practices to improve global food security and protect the environment on land and at sea.
David Lobell
Lobell's research focuses on agriculture and food security, specifically on generating and using unique datasets to study rural areas throughout the world.
Christopher Gardner
Gardener's research focuses on investigating the potential health benefits of various dietary components or food patterns using randomized controlled trials.
Explore More
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Artificial intelligence provides new evidence that rapid decarbonization will not prevent warming beyond 1.5 degrees Celsius. The hottest years of this century are likely to shatter recent records.
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Chris Field writes about impacts of recent unprecedented heat.
