Eating for the Environment

Humane Society International

More than 88 billion land animals were raised and slaughtered for food in 2019, resulting in far-reaching environmental impacts. Animal agriculture is a key driver of climate change and a tremendous contributor to deforestation, water pollution and water use.

The sector accounts for at least 16 percent of global, human-caused greenhouse gas emissions, according to the Food and Agriculture Organization of the United Nations, on par with all transportation in the world combined. Climate-changing gases are released into the atmosphere at nearly every stage of meat, egg, and milk production, potentially disrupting weather, temperature, and ecosystem health.


Worldwide, we use more land to raise and feed farm animals than for any other single purpose. More than 97 percent of soymeal and more than 60 percent of the barley and corn produced globally are fed to farm animals.

Farm animals have degraded approximately one-fifth of global pastures and rangelands. In addition, 70 percent of deforested areas in the South American Amazon have been converted to pasture, while the other 30 percent is used largely to grow animal feed. Land degradation can have a profound impact on our ability to sustain the planet’s vital natural resources, for example resulting in shrinking water supplies and the loss of plant and animal species.

Furthermore, on factory farms, where thousands of animals are confined indoors, the amount of manure produced can exceed the ability of the surrounding land to absorb it. Factory farms can threaten our water, soil, and air by spraying minimally treated or untreated waste on fields.


The farm animal sector is also a major consumer of scarce water resources, making up 29 percent of the global agricultural water requirements. Animal products generally have larger water footprints than non-animal products. For example, in terms of protein, the water footprint is six times bigger for beef, and one and a half times larger for chicken, eggs and milk, than it is for legumes.


Mitigating the serious problems requires immediate and far-reaching changes in current animal agriculture practices and consumption patterns. Each one of us can lessen our environmental footprint by reducing our consumption of meat, egg, and milk products. In the U.S., for example, an average household shifting from a red meat and dairy to a vegetable-based diet just one day a week reduces greenhouse gas emissions equivalent to driving about 1000 miles less per year.

Check out delicious vegetarian recipes to learn how vegetarian eating can improve your personal health and reduce animal suffering while helping to protect the environment.

References include:

Gerber PJ, Steinfeld H, Henderson B, et al. 2013. Tackling climate change through livestock – a global assessment of emissions and mitigation opportunities. Food and Agriculture Organization of the United Nations.

Mekonnen MM and Hoekstra AY. 2012. A global assessment of the water footprint of farm animal products. Ecosystems 15:401-15.

Pew Commission on Industrial Farm Animal Production. 2008. Putting meat on the table: industrial farm animal production in America. Accessed May 18, 2010.

Steinfeld H, Gerber P, Wassenaar T, Castel V, Rosales M, and de Haan C. 2006. Livestock‘s long shadow: environmental issues and options. Food and Agriculture Organization of the United Nations.

Weber CL and Matthews HS. 2008. Food-miles and the relative climate impacts of food choices in the United States. Environmental Science & Technology 42(10):3508-13.

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