TOP FACTS
FOOD & ENVIRONMENT
Here is a list of what we consider the most credible figures and statistics to use based on the entire body of evidence in our database.
Think we should update this or do you have a different interpretation than us? Please contact us directly, we're always open to discussing the evidence:
CLIMATE CHANGE
The choice to adopt a plant based diet was the most underestimated environmental behaviour relative to how beneficial it actually is in reducing greenhouse gas emissions (Ivanova et al., 2020).
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This poll had a base of over 23,000 adults across 31 countries aged 16-74. This study also systematically reviewed almost 7000 peer-reviewed studies, and it was cited in the latest IPCC reports.
The food system accounts for 25-42% of global greenhouse gas emissions, not including carbon drawdown opportunities of freed up land used by animal agriculture (Crippa et al., 2021).
If we shifted to plant based diets, it would be equivalent to reducing about 28% of global greenhouse gas emissions per year (Poore & Nemecek, 2018)
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6.6 Gt of direct CO2e reduced + 8.1 Gt of carbon drawdown opportunity cost per year, of 52.3 Gt of global CO2e = 28%
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Xu et al. (2021) assigns 20% of direct global greenhouse gasses to animal-based foods (35% entire food system/57% from animal-based/29% from plant-based). Note this does not include any carbon drawdown estimate on freed up land used by animal agriculture, which we feel at least a conservative estimate is valid to include.
It's not just about direct emissions, the loss of forests and natural vegetation dating back to the Agricultural Revolution has released a lot of CO2 into the atmosphere. It's equivalent to ~1400 billion t of CO2. For scale, that’s 40 years’ worth of our current emissions from fossil fuels (Erb et al., 2017; Our World in Data)
The average carbon footprint of plant-based foods is 90% lower than that of animal-based foods (Feng et al. 2023).
“Global food system emissions could preclude achieving the 1.5° and 2°C climate change targets” (Ivanovich et al., 2023). “GHG emissions cannot be sufficiently mitigated without dietary changes towards more plant-based diets” (Springmann et al., 2018). Even if fossil fuels were eliminated immediately, emissions from agriculture would still push global warming past safe levels (Clark et al., 2020).
32% of annual human-caused methane (CH4) emissions come from animal agriculture (enteric fermentation and manure).
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United Nations Environment Programme and Climate and Clean Air Coalition (2021). Global Methane Assessment: Benefits and Costs of Mitigating Methane Emissions.
Massive increases in livestock numbers led to an estimated 332% increase in methane emissions from ruminant livestock between 1890 and 2014 - and livestock methane emissions are projected to increase by a further 30% by 2050 without policy interventions (Dangal et al., 2017; Reisinger et al., 2021).
As the IPCC AR6 WGIII report makes clear: “...increasing numbers [of livestock is] directly linked with increasing CH4 emissions... continued global livestock population growth between 1990 and 2019, including increases of 18% in cattle and buffalo numbers, and 30% in sheep and goat numbers, correspond[s] with CH4 emission trends” (p. 771).
You would have to ship a kilo of dried peas roughly 100 times around the world before its greenhouse gasses matched those of a kilo of local beef. Only 1% of beef’s footprint comes from transportation (Monbiot, 2022; Poore & Nemecek, 2018).
If cattle were able to form their own country, they would rank 3rd behind China and the United States among the world’s largest greenhouse gas emitters.
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China (2019): 12.1 billion tonnes CO2e
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United States (2019): 5.8 billion tonnes CO2e
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Cattle (~2010): 5.0 billion tonnes CO2e
Methane emissions related to the dairy industry have increased fourfold over the past 130 years (Zhang et al., 2022)
Methane emissions from wild ruminants are now pegged at just 2 Tg CH₄ annually. In stark contrast, the over 4 billion farmed ruminants globally release 100-120 Tg CH₄ per year - about 40 to 60 times more than their wild counterparts (Saunois et al., 2024). Even at the peak of the last Ice Age, when vast grasslands supported huge herds of wild ruminants like bison, deer, and antelope, they only emitted around 15 Tg CH₄ per year (Saunois et al., 2024).
Most beef cattle will only emit about 11% of their lifetime emissions on feedlot (Rotz et al., 2019) and feed additives that may help reduce emissions only have applicability here. Assuming an 80 percent reduction of emissions on feedlots, where cattle emit 11 percent of their methane, we figured that would make asparagopsis lead to lifetime emissions reductions of about 9 percent.
Chicken has a lower carbon footprint than beef or pork but it’s still three times higher than even the highest emitting plant protein, like soy, and almost ten times higher than peas (Poore & Nemecek, 2018).
LAND USE & DEFORESTATION
Deforestation globally is the second largest emitter of CO2 behind fossil fuels. Every year, the world loses around 5 million hectares of forest. 95% of this occurs in the tropics. Pasture expansion for cattle production is the main driver of deforestation and has been linked to 80% of clearing of the Brazilian Amazon (Skidmore et al., 2021)
Shifting away from animal agriculture completely would free up more than 3 billion hectares of land, equivalent to the size of Africa (Poore & Nemecek, 2018).
We need about 10 billion tonnes of carbon sequestration by 2050 to meet the Paris Agreement. Shifting our food system plant-based gets us 80% of the carbon drawdown we need to achieve the 1.5 degrees C climate target (Poore & Nemecek, 2018).
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- 4700 meters square of land saved per-person
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- Global models and historical evidence show that this land would return to natural vegetation without the economic incentive to keep producing meat and milk, the land would revegetate, removing 8 billion tonnes of CO2 per year for 100 years
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World meat production is expected to double by 2050. This would require that we convert 80% of existing forests and shrubland for meat and dairy production - an additional 35 million km2 of land, equating to the combined area of Australia & Africa (Feigin et al., 2025; Eisen & Brown, 2022).
A dietary shift from animal-based foods to plant-based foods (Eat-Lancet Planetary Health Diet) in high-income nations (only 17% of the population) could spare more than 426.35 Mha—an equivalent area slightly larger than that of the European Union which has benefits beyond carbon sequestration into biodiversity, indigenous land-back programs, etc. (Sun et al., 2022).
Nearly 60 percent of the world's agricultural land is used for beef production, yet beef accounts for less than two percent of the world's calories (Boucher et al., 2012)
Only about 7% of habitable land is used for all crops we eat for food that returns 83% of the entire calories people eat and 62% of all global protein consumed. (Poore & Nemecek, 2018)
42% of global pastureland used to be forests or woody savannas (Searchinger et al., 2018)
More than one-third of U.S. land is used for pasture, making grazing the single largest user of land in the contiguous American states.
In the United States, a switch from beef to beans would free up an estimated 42% of U.S. cropland that could be used for rewilding (Harwatt et al., 2017).
Significant global shifts to plant-based diets by 2050 could lead to sequestration of 332–547 Gt CO2. That's equivalent to 9-16 years of global fossil fuel CO2 emissions (Hayek et al., 2020).
BIODIVERSITY LOSS
Animal agriculture is the most significant driver of habitat loss on the planet (Machovina, Feeley, & Ripple, 2015) and one of the biggest drivers of global biodiversity loss (FAO, Steinfeld et al., 2006).
94% of mammal biomass (excluding humans) is livestock. This means livestock outweigh wild mammals by a factor of 15-to-1 (Bar-On, Phillips & Milo, 2018). Of the 28,000 species evaluated to be threatened with extinction on the IUCN Red List, agriculture and aquaculture is listed as a threat for 24,000 of them (Benton et al., 2021).
Biomass of poultry globally is three times that of all wild bird species and is a major driver of biodiversity loss, largely due to increase demand for feed crops (Bennett et al., 2018).
"Across all animals, livestock exclusion increased abundance and diversity" (Filazzola et al., 2020). This comparison, along with others, shows that ecosystems with extremes in low precipitation or high temp (e.g. deserts) can be particularly impacted by grazing which can further damage soil characteristics, reducing already limited plant biomass, and decreasing animal diversity.
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Meta-analysis of 109 studies on the response of animals or plants to livestock grazing vs. exclusion.
INEFFICIENCY & FEED CROPS
Protein conversion in meat and dairy production is highly inefficient, with only 3.8% of protein from crops fed to cattle being converted into beef, 6.3% for lamb, 8.5% for pork, 19.6% for poultry, 24% for whole milk, and 25% for eggs (Alexander et al., 2016; Our World in Data).
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These numbers are often manipulated by the industry using live-weight feed conversion ratios (FCRs), which show artificially higher efficiency by measuring the weight gain of animals during their lifetime, rather than the actual edible weight after slaughter, which provides a more accurate FCR. Other estimates below:
For every 100 calories of grain fed to farmed animals, you only get:
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🥛 40 calories of milk
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🥚 22 calories of eggs
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🐔 12 calories of chicken
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🐖 10 calories of pork
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🐄 3 calories of beef
“The feed conversion ratio for converting plants into edible meat to produce some traditional animal proteins foods is as follows: beef, between 24:1 and 49:1; pork, between 3:1 and 9:1; chicken and turkey, approximately 2:1 to 5.4:1; dairy, approximately 2.4:1; eggs, approximately 2.4:1; salmon, approximately 1.3:1; and marine fish, approximately 1.9:1” (Gardner et al., 2019) (Shepon et al., 2016).
Only about 17% of protein used as feed ends up in human diets (Leip et al., 2022).
More than three-quarters (77%) of global soy is fed to livestock for meat and dairy production. Most of the rest is used for biofuels, industry or vegetable oils. Just 7% of soy is used directly for human food products such as tofu, soy milk, edamame beans, and tempeh (Fraanje & Garnett, 2020).
REGENERATIVE AGRICULTURE MYTH
"Agricultural soils contain 25% to 75% less SOC than their counterparts in undisturbed or natural ecosystems" (Lal, 2010)
If all grassland soil carbon is restored to its full potential (12-24Gt CO2), this would offset less than 1-2% of global greenhouse emissions each year, until the soil reaches its capacity. (Sanderman, Hengl, & Fiske, 2017)
Don't rely on soil C to offset livestock emissions: "About 135 gigatonnes of carbon is required to offset the continuous methane and nitrous oxide emissions from ruminant sector worldwide, nearly twice the current global carbon stock in managed grasslands" (Wang et al., 2023)
In a scenarios where we shift to grass-finished beef:
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Methane would increase by 43% (per unit)
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More land would be used (+25%)
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Only 27% of current US beef could be produced
"Only under very specific conditions can [grazing] help sequester carbon. This sequestering of carbon is even then small, time-limited, reversible and substantially outweighed by the GHG emissions these grazing animals generate." (Garnett et al., 2017).
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The maximum global potential (of carbon sequestered in these soils), in the most optimistic conditions and using the most generous of assumptions, would offset only “20%-60% of emissions from grazing cows, 4%-11% of total livestock emissions, and 0.6%-1.6% of total annual greenhouse gas emissions” (Garnett et al., 2017).
OCEANS & DEAD ZONES
“Fishing has a footprint four times larger than agriculture, in which more than the 70,000 reported industrial fishing vessels cover at least 55% of the oceans − with hotspots for fishing in the northeast Atlantic, northwest Pacific, and upwelling regions off South America and West Africa” (IPBES, 2019)
66% of the marine environment is severely altered by human actions. By the year 2100, without significant changes, more than half of the world’s marine species may be close to extinction.
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Sharks are less than 10% of their original population
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Most whales are less than 1% of original populations
The global abundance of oceanic sharks and rays has declined by 71% over the last 50 years, due primarily to an 18-fold increase in fishing pressure since 1970.
Right now, 8 percent of the ocean is protected, and only 2.6 percent of those MPAs are considered strongly protected and fully off-limits to fishing (Marine Conservation Institute).
78% of global ocean and freshwater eutrophication (the pollution of waterways with nutrient-rich pollutants) is caused by agriculture (Poore & Nemecek, 2018).
“Entanglement in fishing gear is one of the key threats facing North Atlantic right whales. Almost all females, 89%, have experienced at least one entanglement event during their lifetime, and almost two-thirds of these have experienced two or more, with many resulting in injury or mortality” (Reed et al., 2024).
Only 3% of fishing is for subsistence.
If we restored global fish populations to preindustrial fishing levels, they would cycle more than eleven times the carbon potential of whales: 18.9 billion tons—60% of global annual emissions (Bianchi et al., 2021).
OVERALL STATEMENTS
“Global food production is the single largest human pressure on Earth, threatening local ecosystems, driving a sixth mass extinction of species, and impacting the stability of the entire Earth system.” (Loken, 2020)
Scientist and Project Drawdown’s leader Dr. Jonathan Foley states that “nothing else we do has come close to how food, agriculture, and land use are causing global environmental harm. Without major changes, our food system will continue to push Earth well beyond its planetary boundaries.” (Loken, 2020)
The plant-predominant Planetary Health Diet could reduce enough emissions to keep us below 1.5 degrees of warming. This diet, for the US, involved a reduction of beef, lamb and pork by 84%, eggs by 63%, poultry by 57%, and dairy by 31%. However, this is assuming that everyone will adhere to the diet, we also eliminate fossil fuel use entirely, and it only gets us to a 50% chance at staying below 1.5 degrees of warming. Considering most nations can’t even promise to reduce half the emissions we need, some might conclude changing our diets even more may be prudent. A completely plant based diet could get us to a 85% chance at staying below 1.5 degrees.