Editing Plant-based diet (section)

== Sustainability ==
{{Main|Sustainable diet}}
{{Pie chart
 | caption = '''[[Biomass (ecology)|Biomass]] of [[mammal]]s on Earth'''<ref name="Carrington"/>
 | label1  = Livestock, mostly cattle and pigs
 | value1  = 60 | color1 = blue
 | label2  = Humans
 | value2  = 36 | color2 = red
 | label3  = [[Wildlife|Wild mammals]]
 | value3  = 4  | color3 = green
 }}

There is scientific consensus that plant-based diets offer lower [[greenhouse gas emissions]], land use and biodiversity loss. In addition, dietary patterns that reduce diet-related mortality also promote environmental sustainability.<ref name=":0">{{cite journal | vauthors = Poore J, Nemecek T | title = Reducing food's environmental impacts through producers and consumers | journal = Science | volume = 360 | issue = 6392 | pages = 987–992 | date = June 2018 | pmid = 29853680 | doi = 10.1126/science.aaq0216 | doi-access = free | bibcode = 2018Sci...360..987P }}</ref><ref>{{Cite journal|last1=Carey |first1=Cassandra N. |last2=Paquette |first2=Melanie |last3=Sahye-Pudaruth |first3=Sandhya |last4=Dadvar |first4=Abolfazl |last5=Dinh |first5=Dorothy |last6=Khodabandehlou |first6=Khosrow |last7=Liang |first7=Fred |last8=Mishra |first8=Ekta |last9=Sidhu |first9=Mandeep |last10=Brown |first10=Ramon |last11=Tandon |first11=Shilpa |last12=Wanyan |first12=Jessica |last13=Bazinet |first13=Richard P. |last14=Hanley |first14=Anthony J. |last15=Malik |first15=Vasanti |date=2023-02-06 |title=The Environmental Sustainability of Plant-Based Dietary Patterns: A Scoping Review |journal=The Journal of Nutrition |volume=153 |issue=3 |pages=S0022–3166(23)06589–6 |doi=10.1016/j.tjnut.2023.02.001 |issn=1541-6100 |pmid=36809853|s2cid=256652205 |doi-access=free }}</ref><ref>{{cite journal |last1=Hedenus |first1=Fredrik |last2=Wirsenius |first2=Stefan |last3=Johansson |first3=Daniel J. A. |title=The importance of reduced meat and dairy consumption for meeting stringent climate change targets |journal=[[Climatic Change (journal)|Climatic Change]] |date=2014 |volume=124 |issue=1–2 |pages=79–91 |doi=10.1007/s10584-014-1104-5 |doi-access=free|bibcode=2014ClCh..124...79H }}</ref>

As a significant percentage of crops around the world are used to feed livestock rather than humans, eating less animal products helps to [[Greenhouse gas emissions from agriculture|limit climate change]] (such as through [[low-carbon diet]]s) and [[biodiversity loss]].<ref>{{Cite web|url=http://www.fao.org/3/ar591e/ar591e.pdf|title=Sustainability pathways: Livestock and landscapes|publisher=Food and Agriculture Organization, United Nations|date=2012|access-date=5 June 2019}}</ref> Especially beef, lamb and cheese have a very high carbon footprint.<ref>{{Cite web |last=Torrella |first=Kenny |date=1 February 2022 |title=This is how much meat and dairy hurt the climate |url=https://www.vox.com/future-perfect/22905381/meat-dairy-eggs-climate-change-emissions-rewilding |access-date=2022-07-03 |website=Vox |language=en}}</ref> While soy cultivation is a "major driver of deforestation in the [[Amazon rainforest|Amazon]] basin",<ref>{{Cite web|url=https://globalforestatlas.yale.edu/amazon/land-use/soy|title=Soy agriculture in the Amazon Basin|date=2019|publisher=Yale University|access-date=5 June 2019|archive-date=5 June 2019|archive-url=https://web.archive.org/web/20190605185853/https://globalforestatlas.yale.edu/amazon/land-use/soy|url-status=dead}}</ref> the vast majority of soy crops are used for livestock consumption rather than human consumption.<ref>{{Cite web|url=https://www.forbes.com/sites/michaelpellmanrowland/2018/06/12/save-the-planet/|title=The most effective way to save the planet| vauthors = Rowland MP |work=Forbes|quote=meat and dairy provide only 18% of our calories and 37% of our protein, yet use up 83% of our farmland.|access-date=5 June 2019}}</ref> Adopting plant-based diets could also reduce the number of animals raised and killed for food on [[Intensive animal farming|factory farms]].<ref>{{cite news | vauthors = Torrella K |date=22 April 2022 |title=The difference you make when you eat less meat |url=https://www.vox.com/future-perfect/2022/4/22/23036010/eat-less-meat-vegetarian-effects-climate-emissions-animal-welfare-factory-farms |work=[[Vox (website)|Vox]] |location= |access-date=18 May 2022}}</ref>

[[File:A_third_of_Europeans_say_that_most_of_us_will_switch_to_a_plant-based_diet_within_20_years.jpg|thumb|European respondents to a climate survey conducted in 2021–2022 by the [[European Investment Bank]] say that most people will switch to a plant-based diet within 20 years to help the environment.]]

Research from 2019 on six diets found the plant-based diets more environmentally friendly than the diets higher in animal-sourced foods. Of the six mutually-exclusive diets; individuals eating [[Veganism|vegan]], vegetarian and [[Pescetarianism|pescetarian]] diets had lower dietary-carbon footprints than typical [[Omnivore#Etymology and definitions|omnivorous diets]], while those who ate '[[Paleolithic diet|paleolithic]]' and [[ketogenic diet]]s had higher dietary-carbon emissions due to their animal sourced foods.<ref>{{Cite journal| vauthors = O'Malley K, Willits-Smith A, Aranda R, Heller M, Rose D |date=1 June 2019|title=Vegan vs Paleo: Carbon Footprints and Diet Quality of 5 Popular Eating Patterns as Reported by US Consumers (P03-007-19)|url= |journal=Current Developments in Nutrition|volume=3 |issue=Suppl 1|pages=nzz047.P03–007–19|doi=10.1093/cdn/nzz047.P03-007-19|issn=2475-2991|pmc=6574879}}</ref>

A 2020 study found that the [[climate change mitigation]] effects of [[decision-making|shifting]] worldwide [[food production]] and [[food consumption|consumption]] to plant-based diets, which are mainly composed of foods that require only a small fraction of the land and CO<sub>2</sub> emissions required for [[environmental impact of meat|meat]] and dairy, could offset CO<sub>2</sub> emissions equal to those of past 9 to 16 years of fossil fuel emissions in nations that they grouped into 4 types. The researchers also provided a map of approximate regional opportunities.<ref>{{cite news |title=Changing what we eat could offset years of climate-warming emissions, new analysis finds |url=https://phys.org/news/2020-09-offset-years-climate-warming-emissions-analysis.html |access-date=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal | vauthors = Hayek MN, Harwatt H, Ripple WJ, Mueller ND |title=The carbon opportunity cost of animal-sourced food production on land |journal=Nature Sustainability |date=7 September 2020 |volume=4 |issue=1 |pages=21–24 |doi=10.1038/s41893-020-00603-4 |bibcode=2020NatSu...4...21H |s2cid=221522148 |url=https://www.nature.com/articles/s41893-020-00603-4 |access-date=9 October 2020 |language=en |issn=2398-9629|url-access=subscription }}</ref>

It may be possible to increase the transition from meat eating to a plant based diet through [[social contagion]], by which behaviour, emotions, or conditions spread spontaneously through a group or [[Social network|network]]. A Max Planck Institute study from 2020 found that when meat-eaters are accompanied by vegetarians and have a choice of eating dishes with or without meat, they're more likely to choose a vegetarian dish. This probability increases as the number of vegetarians accompanying the meat eaters increases.<ref>{{cite web |last1=Einhorn |first1=Laura |title=Normative Social Influence on Meat Consumption |url=https://pure.mpg.de/rest/items/item_3196378_1/component/file_3204446/content |website=MPG.PuRe |publisher=Max Planck Society |access-date=17 February 2024}}</ref> Once enough people have been influenced, the community can reach a [[Tipping point (sociology)|tipping point]], in which a majority of people transition to a new habit; a 2018 study published in Nature claims that with only 25 per cent of a population, a minority perspective was able to overturn the majority.<ref>{{cite journal |last1=Centola |first1=Damon |last2=Becker |first2=Joshua |last3=Brackbill |first3=Devon |title=Experimental evidence for tipping points in social convention |journal=Science |date=8 Jun 2018 |volume=360 |issue=6393 |pages=1116–1119 |doi=10.1126/science.aas8827 |pmid=29880688 |bibcode=2018Sci...360.1116C |url=https://www.science.org/doi/10.1126/science.aas8827 |access-date=17 February 2024}}</ref>

According to a 2021 [[Chatham House]] report, supported by the [[United Nations Environment Programme]], a shift to "predominantly plant-based diets" will be needed to reduce [[biodiversity loss]] and [[human impact on the environment]]. The report said that livestock has the largest environmental impact, with some 80% of all global farmland used to rear cattle, sheep and other animals used by humans for food. Moving towards plant-based diets would free up the land to allow for the restoration of ecosystems and the flourishing of biodiversity.<ref name="Carrington">{{cite news| vauthors = Carrington D |date=3 February 2021 |title=Plant-based diets crucial to saving global wildlife, says report |url=https://www.theguardian.com/environment/2021/feb/03/plant-based-diets-crucial-to-saving-global-wildlife-says-report |work=[[The Guardian]] |location= |access-date=4 February 2021}}</ref>

A 2022 study published in ''[[Nature Food]]'' found that if high-income nations switched to a plant-based diet, vast swaths of land used for animal agriculture could be allowed to [[Restoration ecology|return to their natural state]], which in turn has the potential to pull 100&nbsp;billion tons of {{CO2}} out of the atmosphere by the end of the century. Around 35% of all habitable land around the world is used to rear animals used by humans in food production.<ref>{{cite news |title=How plant-based diets not only reduce our carbon footprint, but also increase carbon capture |url=https://phys.org/news/2022-01-plant-based-diets-carbon-footprint-capture.html |access-date=14 February 2022 |work=[[Leiden University]] |language=en}}</ref><ref>{{cite journal | vauthors = Sun Z, Scherer L, Tukker A, Spawn-Lee SA, Bruckner M, Gibbs HK, Behrens P |title=Dietary change in high-income nations alone can lead to substantial double climate dividend |journal=Nature Food |date=January 2022 |volume=3 |issue=1 |pages=29–37 |doi=10.1038/s43016-021-00431-5 |pmid=37118487 |s2cid=245867412 |language=en |issn=2662-1355 |url=https://www.researchgate.net/publication/357723207 |url-access=subscription}}</ref>

A 2023 study published in ''Nature Food'' found that a [[vegan]] 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 of [[wildlife]] by 66% and the usage of water by 54%.<ref>{{cite news |last1=Carrington |first1=Damian |title=Vegan diet massively cuts environmental damage, study shows |url=https://www.theguardian.com/environment/2023/jul/20/vegan-diet-cuts-environmental-damage-climate-heating-emissions-study |access-date=20 July 2023 |work=[[The Guardian]] |date=20 July 2023}}</ref> Another study published in the same year in ''[[Nature Communications]]'' found that replacing half of the beef, chicken, dairy and pork products consumed by the global population with [[Meat alternative|plant-based alternatives]] could reduce the amount of land used by agriculture by almost a third, bring deforestation to a near-halt, restore biodiversity, and reduce GHG emissions from agriculture by 31% by 2050. However, the report also notes that a [[Population growth|growing population]] and rising [[Wealth|affluence]] are projected to increase demand for animal products which could have negative impacts on the environment.<ref>{{cite news |last=Marashli|first=Imran |date=September 16, 2023 |title=Meat, milk alternatives could slash food system emissions a third: study|url=https://phys.org/news/2023-09-meat-alternatives-slash-food-emissions.html|work=[[Phys.org]]|location= |access-date=October 19, 2023}}</ref><ref>{{cite journal |last1=Kozicka|first1=Marta |last2=Havlík|first2=Petr|last3=Valin|first3=Hugo |display-authors=etal.|date=2023 |title=Feeding climate and biodiversity goals with novel plant-based meat and milk alternatives|url= |journal=Nature Communications|volume=14 |issue=5316 |page=5316 |doi=10.1038/s41467-023-40899-2|access-date=|doi-access=free|pmid=37699877 |pmc=10497520 |bibcode=2023NatCo..14.5316K |hdl=10568/131912|hdl-access=free}}</ref><ref>{{cite news |last=Graham |first=Max |date=September 14, 2023 |title=New Study Shows Impacts of Cutting Meat and Dairy Consumption in Half|url=https://www.motherjones.com/environment/2023/09/meat-dairy-consumption-farming-livestock-climate-emissions/|work=[[Mother Jones (magazine)|Mother Jones]] |location= |access-date=October 19, 2023}}</ref>