Environmental vegetarianism is the practice ofvegetarianism that is motivated by the desire to create asustainable diet, which avoids thenegative environmental impact of meat production. Livestock as a whole is estimated to be responsible for around 15% of globalgreenhouse gas emissions.[2][a] As a result, significant reduction in meat consumption has been advocated by, among others, theIntergovernmental Panel on Climate Change in their 2019 special report[3] and as part of the 2017World Scientists' Warning to Humanity.[4][5]
Other thanclimate change, the livestock industry is the primary driver behindbiodiversity loss anddeforestation and is significantly relevant to environmental concerns such aswater and land use,pollution, andunsustainability.[6][7][8][9]
Four-fifths of agricultural emissions arise from the livestock sector.[10]
According to the 2006Food and Agriculture Organization of the United Nations (FAO) reportLivestock's Long Shadow, animal agriculture contributes on a "massive scale" toglobal warming, air pollution,land degradation, energy use,deforestation, andbiodiversity decline.[11] The FAO report estimates that thelivestock (including poultry) sector (which provides draft animal power, leather, wool, milk, eggs, fertilizer, pharmaceuticals, etc., in addition to meat) contributes about 18 percent of global GHG emissions expressed as 100-yearCO2 equivalents.[b] This estimate was based onlife-cycle analysis, including feed production,land use changes, etc., and used GWP (global warming potential) of 23 for methane and 296 fornitrous oxide, to convert emissions of these gases to 100-year CO2 equivalents. The FAO report concluded that "the livestock sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global".[11] The report found that livestock's contribution to greenhouse gas emissions was greater than that of the global transportation sector.
A 2009 study by theWorldwatch Institute argued that the FAO's report had underestimated impacts related to methane, land use and respiration, placing livestock at 51% of total global emissions.[12]
| Diet | Mean dietary emissions (In kilograms of carbon dioxide equivalents) |
|---|---|
| All meat-eaters | 5.93 |
| High meat-eaters ( ≥ 100 g/day) | 7.19 |
| Medium meat-eaters (50–99 g/day) | 5.63 |
| Low meat-eaters ( < 50 g/day) | 4.67 |
| Fish-eaters | 3.91 |
| Vegetarians | 3.81 |
| Vegans | 2.89 |
A 2003 paper published in theAmerican Journal of Clinical Nutrition, after calculating effects on energy, land, and water use, concluded that meat-based diets require more resources and are less sustainable thanlacto-ovo vegetarian diets.[15] "The water required for a meat-eating diet is twice as much needed for a 2,000-litre-a-day vegetarian diet".[16]
Animal production has a large impact on water pollution and usage. According to the Water Education Foundation, it takes 2,464 gallons of water to produce one pound of beef in California, whereas it takes only 25 gallons of water to produce one pound of wheat.[17] Raising a large amount of livestock creates a massive amount of manure and urine, which can pollute natural resources by changing the pH of water, contaminates the air, and emits a major amount of gas that directly affects global warming. As most livestock are raised in small confined spaces to cut down on cost, this increases the problem of concentrated waste. Livestock in the United States produces 2.7 trillion pounds of manure each year, which is ten times more than what is produced by the entire U.S. population. There are issues with how animal waste is disposed, as some is used as fertilizer while some farmers create manure lagoons which store millions of gallons of animal waste which is extremely unsafe and detrimental to the environment.[17]
Massive reductions in meat consumption inindustrial nations will ease the health care burden while improving public health; declining livestock herds will take pressure off rangelands and grainlands, allowing the agricultural resource base to rejuvenate. As populations grow, lowering meat consumption worldwide will allow more efficient use of declining per capita land and water resources, while at the same time making grain more affordable to the world's chronically hungry.[18]
Although motivations frequently overlap, environmental vegetarians and vegans can be contrasted with those who are primarily motivated by concerns aboutanimal welfare (one kind ofethical vegetarianism), health, or who avoid meat to save money or out of necessity (economic vegetarianism).[19][20] Some also believe vegetarianism will improve global food security, or curbstarvation.
A 2018 report published inPNAS asserted that farmers in the United States could sustain more than twice as many people than they do currently if they abandoned rearing farm animals for human consumption and instead focused on growing plants.[21]
For developed countries, a CAST report estimates an average of 2.6 pounds of grain feed per pound of beef carcass meat produced. For developing countries, the estimate is 0.3 pounds per pound. (Some very dissimilar figures are sometimes seen; the CAST report discusses common sources of error and discrepancies among such figures.)[22] In 2007, US per capita beef consumption was 62.2 pounds per year, and US per capita meat (red meat plus fish plus poultry) consumption totaled 200.7 pounds (boneless trimmed weight basis).[23]
_2001-2003_(FAO).svg)
Globalization and modernization has resulted in Western consumer cultures spreading to countries like China and India, including meat-intensive diets which are supplanting traditionalplant-based diets. Around 166 to more than 200 billion land and aquatic animals are consumed by a global population of over 7 billion annually, which philosopher and animal rights activistSteven Best argues is "completely unsustainable".[25][26] A 2018 study published inScience states that meat consumption is set to increase by some 76% by 2050 as the result ofhuman population growth and rising affluence, which will increasegreenhouse gas emissions and furtherreduce biodiversity.[27][28]
A 2018 report inNature found that a significant reduction in meat consumption is necessary tomitigate climate change, especially as the population rises to a projected 10 billion in the coming decades.[29] According to a 2019 report inThe Lancet, global meat consumption needs to be reduced by 50 percent to mitigate for climate change.[30]
In November 2017, 15,364 world scientists signed aWarning to Humanity calling for, among other things, drastically diminishing our per capita consumption of meat.[31]
In November 2019, a warning on the "climate emergency" from over 11,000 scientists from over 100 countries said that "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 (including methane in the “Short-lived pollutants” step)." The warning also says it 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."[32][33]
A 2020 study by researchers from theUniversity of Michigan andTulane University, which was commissioned by theCenter for Biological Diversity, asserts that if the U.S. cut its meat consumption by half, it could result in diet-related GHG emissions being reduced by 35%, a decline of 1.6 billion tons.[34]
A 2019 correction to a major 2018 study inScience of food's impact on the environment found that, after the negative emissions of land use change were accounted for, eliminating animal products from the food system would reduce total global greenhouse gas emissions from all sectors by 28%.[7][35]
A 2018 study found that global adoption of plant-based diets would reduce agricultural land use by 76% (3.1 billion hectares, an area the size of Africa) and cut total globalgreenhouse gas emissions by 28%. Half of this emissions reduction came from avoided emissions from animal production includingmethane andnitrous oxide, and half from trees re-growing on abandoned farmlands that remove carbon dioxide from the air.[36][37] The authors conclude that avoiding meat and dairy is the "single biggest way" to reduce one's impact on Earth.[38]
The 2019IPBESGlobal Assessment Report on Biodiversity and Ecosystem Services found thatindustrial agriculture andoverfishing are the primary drivers of the extinction crisis, with the meat and dairy industries having a substantial impact.[39][40] On 8 August 2019, the IPCC released a summary of the 2019 special report which asserted that a shift towards plant-based diets would help to mitigate and adapt to climate change.[41]
A 2022 study found that for high-income nations alone 100 billion tons of carbon dioxide could be removed from the air by the end of the century through a shift to plant-based diets and re-wilding of farmlands. The researchers coined the termdouble climate dividend to describe the effect that re-wilding after a diet shift can have.[42][43] But they note: "We don't have to be purist about this, even just cutting animal intake would be helpful. If half of the public in richer regions cut half the animal products in their diets, you're still talking about a massive opportunity in environmental outcomes and public health".[44]
A 2023 study published inNature Food found that avegan diet vastly decreases the impact on the environment from food production, such as reducing emissions, water pollution and land use by 75%, reducing the destruction ofwildlife by 66% and the usage of water by 54%.[45]
In 2015, researches fromCarnegie Mellon University claimed that environmental vegetarianism appears more harmful than helpful to our environment. Environmental vegetarianism actually takes moreenvironmental costs, environmentally and financially, which backfires. Paul Fischbeck, Michelle Tom, andChris Hendrickson, researchers incivil and environmental engineering atCarnegie Mellon University, investigated the impact of America's obesity crisis on the environment by analyzing the food supply chain's resource usage. The study offers a nuanced exploration into the environmental impact of dietary choices, specifically contrasting the perceived benefits ofvegetarian andUSDA-recommended "healthier" diets against their ecological footprints. The research underscores that while reducing overall calorie intake can decrease the environmental burden by around 9%, opting for diets heavy infruits,vegetables,dairy, andseafood significantly increases resource demands—leading to a 38% rise in energy consumption, a 10% increase in water use, and a 6% uptick in greenhouse gas emissions.[46]
In 2019,Loma Linda University School of Public Health published a research article which outlined that while, generally, vegetarian diet is more environmentally sustainable than omnivorous diet, its environmental benefits heavily depend on the specific foods included in the diet.[47] This way, if beef is replaced by a larger quantity ofdairy, the environmental benefit of such a switch may be close to zero.[48] Similarly, if the vegetarian diet includes out-of-season fruits or vegetables cultivated in high-energy-consumptiongreenhouses, theGHG emissions offset could ultimately be reversed.[49]
Evidence suggests that intensive livestock farming is a poor solution to world hunger, given its impact on personal health and the environment, but intensive industrialised farming of soya, maize and grains comes at a significant carbon cost, too – as does flying in the ingredients to keep berries and nut butters on acai bowls or avocado on toast.[50]
If U.S. farmers took all the land currently devoted to raising cattle, pigs and chickens and used it to grow plants instead, they could sustain more than twice as many people as they do now, according to a report published Monday in the Proceedings of the National Academy of Sciences.
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. It is far bigger than cutting down on your flights or buying an electric car
A vegan always tries to avoid any cruelty and undue exploitation of all animals including humans and protect the environment.
Pushing all this forward, though, are increased demands for food from a growing global population and specifically our growing appetite for meat and fish.
Agriculture and fishing are the primary causes of the deterioration. Food production has increased dramatically since the 1970s, which has helped feed a growing global population and generated jobs and economic growth. But this has come at a high cost. The meat industry has a particularly heavy impact. Grazing areas for cattle account for about 25% of the world's ice-free land and more than 18% of global greenhouse gas emissions.