The cost of livestock and meat consumption on human health and the healthcare system

by

Key points:

  • Livestock production and the consumption of meat significantly affect planetary and human health. 
  • Consumption of meat is associated with a higher risk of non-communicable diseases, such as heart disease, diabetes and cancer, as well as impaired cognitive functioning. Diets high in red meat were responsible for 0.9 million deaths and 23.9 million disability-adjusted life years (DALYs) worldwide in 2019.
  • Animal farming is linked to the spread of zoonotic disease and other illnesses, as well as anti-microbial resistance and pollution. For example, agricultural drivers are associated with over half of zoo notic diseases, which cause approximately 2.5 billion cases of illness and 2.7 million deaths each year. Increased anti-microbial resistance in 2050 is estimated to result in USD 100 trillion due to productivity losses.    
  • These impacts have been quantified to a varying degree, outlining the extent of the cost of meat consumption and the externalities associated with livestock production. This has considerable costs to human health and the health sector, estimated at 2.4 million deaths and USD 285 billion in 2020 due to red and processed meat consumption alone. 
  • Multiple studies highlight that reducing meat consumption and production can have significant health and economic benefits. A dietary shift away from animal-sourced foods could save up to USD 7.3 trillion in avoided health burden and ecosystem degradation costs associated with production, while cutting emissions.


Negative health outcomes associated with meat 

High intake of red and processed meat has been linked to increased risk of many non-communicable diseases (NCDs), such as heart disease, type 2 diabetes, obesity and numerous cancers. 

Heart disease

Heart disease is the leading cause of death globally, responsible for 13% of the world’s total deaths in 2021. UK-based research has found that the risk of hospitalisation or death from heart disease is 32% lower in vegetarians than non-vegetarians. A 2019 study found after adjusting for factors such as smoking and exercising, non-meat eaters in the UK had a 22% lower rate of heart disease than meat eaters. This is equivalent to 10 fewer cases of heart disease in vegetarians compared to meat-eaters per 1,000 population over 10 years. 

These health impacts are clear, even in spite of industry efforts to obscure them. A recent analysis of 44 studies on the cardiovascular health impacts of red meat consumption found that those funded by the red meat industry all reported the health impacts as being neutral or positive, as opposed to independent studies, which found 73% of cases were negative and the rest neutral.

Cancer

The International Agency for Research on Cancer (IARC) has categorised processed meat as carcinogenic to humans and red meats as “probably carcinogenic” to humans. The IARC estimates that the risk of developing stomach cancer increased by 17% per 100g-per-day increment of red meat consumed. Analysis based on UK data estimates that vegetarians and vegans, respectively, had a 11% and 19% lower risk of cancer overall when compared to meat eaters. Another UK study found that people who consume red and processed meat four or more times per week have a 20% increased risk of colorectal cancer compared with those who consume it less than twice a week. In China, the number of colorectal cancer deaths due to high meat consumption increased nearly 2.5 times between 1990 and 2021.

Diabetes

A 2024 analysis of 1.97 million adults in 20 countries highlighted that greater consumption of meat, including poultry but particularly processed meat and unprocessed red meat, is a risk factor for developing type 2 diabetes. A UK-based study found that those who ate at least 50g of meat a day were at higher risk of developing diabetes than those who followed other diets. For example, the risk of developing diabetes in the vegetarian group was 37% lower (11% lower after adjusting for body mass index).

Impacts on cognitive function

Adverse effects of long-term high-protein or high-meat consumption in humans is also associated with impacts on bone, kidney and liver function, as well as on cognitive function. For example, a 2025 study of the diets of healthcare professionals in the US found that eating processed red meat was linked to a 16% higher risk of dementia and a faster rate of cognitive ageing. The study found that substituting one serving of processed red meat with nuts, tofu or beans reduced dementia risk by 19%. 

The overall impact of high-meat diets on the incidence of NCDs

Diets high in red meat were responsible for 0.9 million deaths and 23.9 million disability-adjusted life years (DALYs) worldwide in 2019. This was mainly due to heart disease, diabetes and colorectal cancer. Total deaths and DALYs attributable to a diet high in red meat increased by over 50% between 1990 and 2019. Overall death and illness rates during this period went down once adjusted for age (meaning that, compared to people of the same age, fewer died or got sick). At the same time, the level of exposure to this risk went up by 8.3%, meaning more people were eating high levels of red meat. 

Reducing consumption of red and processed meat can lower health and mortality risks. Implementation of the EAT-Lancet planetary health diet, which is rich in fruits, vegetables, legumes, nuts and whole grains, with small amounts of meat, dairy and fish, could prevent 11 million deaths per year globally while keeping emissions in line with climate targets. 

A recent analysis of data from 200,000 healthcare professionals in the US found that the 10% of people who followed a diet most closely aligned with the planetary health diet had a 30% lower risk of dying from all causes – including heart disease, cancer, respiratory disease and also neurodegenerative conditions like Alzheimer’s and Parkinson’s disease. Similarly, in Sweden, those adhering closely to the planetary health diet had a 25% lower risk of mortality. 

A 2024 report from the Lancet estimated that a 30% reduction in both processed and red meat consumption in the US could lead to 1.07 million fewer occurrences of type 2 diabetes, 382,400 fewer occurrences of cardiovascular disease, 84,400 fewer instances of colorectal cancer and 62,200 fewer deaths over a ten-year period. Another study of health professionals utilising data from the 1980s to 2008 in the US estimated that almost one in 10 deaths in males and close to one in 12 deaths in females could have been prevented if everyone had eaten less than half a serving of meat (42g) a day, due to the substantial reduction in risk of death from cancer and heart disease. 

Studies have come to similar conclusions in Canada and the UK. An analysis of Canadian diet statistics data modelled the outcomes of replacing half of red and processed meat consumption with plant-based proteins. The researchers found that this increased life expectancy by almost nine months, while also cutting diet-related carbon footprint by 25%. In the UK, a 2012 study estimated that a 50% reduction in meat and dairy replaced by fruit, vegetables and cereals could result in 36,910 fewer deaths from heart disease, stroke and cancer per year – a 16% reduction from the baseline. 

Economic burden of diets high in red meat

Country-level studies have highlighted the economic costs of high meat consumption and the potential benefits of reducing intake.

Health impacts associated with raising livestock 

The human health implications of animal agriculture go well beyond those due to direct consumption. The way animals are raised for human consumption can have negative impacts on health, particularly industrial-scale animal agriculture, which contributes to antibiotic resistance, zoonotic disease and increased pollution. 

Zoonotic disease 

Around 75% of emerging infectious diseases are transmissible between humans and animals. These are referred to as zoonotic diseases and cause approximately 2.5 billion cases of illness and 2.7 million deaths each year, according to one estimate from a 2012 study. Agricultural drivers have been associated with over half of zoonotic diseases since 1940, according to a 2019 study, with the spread of more zoonotic diseases anticipated in the future due to the expansion of intensive animal farming and the encroachment of agriculture on nature. 

The number of zoonotic spillover events – where transmission crosses from one species to another – that pose significant public health, economic or political stability risk, and reported deaths has been increasing by almost 5% each year since the early 1960s. If this continues, by 2050 there would be four times more spillover events and 12 times more deaths compared to 2020.

The recent outbreak of bird flu H5N1 in the US, which has recently spread to dairy cows and humans, highlights how large industrial livestock operations can amplify the spread of disease. As of April 2024, 70 people had caught the virus, almost all of whom had been exposed on animal farms.

While the outbreak of COVID-19 was not linked to industrial agriculture, it highlights the extent of the human and economic costs that can occur from the spread of zoonotic disease. For example, the World Health Organisation (WHO) estimates that 7.1 million deaths worldwide were attributed to COVID-19 as of 30 March 2025. Research suggests that the pandemic cost the US economy almost USD 14 trillion by 2023.

Antimicrobial resistance

A heavy reliance on antibiotics in industrial-scale animal agriculture is contributing to antibiotic resistance in humans – causing increased mortality, morbidity and social and economic costs. It is estimated that by 2050, 10 million global deaths each year will be attributable to antimicrobial resistance. Additionally, between 2016 and 2050, this would result in a cumulative economic cost of USD 100 trillion due to productivity losses. Already, some 700,000 people die every year from drug-resistant infections.

Research suggests that limiting meat intake to 40g a day – “the equivalent of one standard fast-food burger per person” – could reduce antimicrobial use in animals raised for consumption by 66% globally. 

Foodborne illness and disease

In the US, it is estimated that meat and poultry products are the sources of 22% of foodborne illnesses and are responsible for 29% of deaths from foodborne illnesses. Estimates suggest foodborne illness from meat and poultry in the US amounted to 2.9 million annual illnesses and economic costs of up to USD 20.3 billion. 

Additionally, the outbreak of other diseases in the livestock industry that are not transmitted to humans can have significant costs, many of which are covered by public sources, reducing resources that could instead go towards other areas, such as the healthcare sector. For example, the 2001 foot-and-mouth outbreak cost UK taxpayers £3 billion (USD 8.4 billion in 2025 values) and resulted in  private sector losses over £5 billion (USD 14.0 billion in 2025 values). 2USD figures are shown in 2025 values using XE currency converter on 16 April 2025. The recent outbreak of bird flu in the US has already amounted to costs exceeding USD 1.4 billion as of November 2024. 

Pollution

The environmental impacts of producing large amounts of feed and pollutants that arise from livestock operations make agriculture a major contributor to air, water and soil pollution. 

Air pollution is the largest environmental risk factor for mortality worldwide. In the US, it was estimated that poor air quality caused by food production is responsible for around 15,900 deaths a year. Of these, 80% (12,700 deaths) are attributable to animal-based foods, both from the rearing of animals and through growing crops for animal feed. Globally, adopting diets with less meat and more plant-based foods could reduce mortality associated with agricultural air pollution by up to 83% while still providing sufficient levels of protein and other nutrients. The paper found that adopting vegetarian, vegan or flexitarian diets could save up to 13,100 lives, while substituting red meat consumption with poultry could prevent 6,300 deaths.  

Agricultural burning related to livestock production is also responsible for elevated levels of air pollution in some countries. In Thailand, burning of maize residues – a crop almost entirely grown for animal feed  – results in levels of fine particulate matter (PM2.5) that are three times higher than the acceptable national standard in the burning season. Agricultural burning is associated with 34,000 premature deaths currently in Thailand, and could increase to up to 361,000 by 2050 on current livestock production trends. Replacing half of meat and seafood production with plant proteins could save 100,000 lives lost from air pollution in Thailand, according to a study by environmental research groups. 

Additionally, livestock farmers are more likely to suffer from a variety of health conditions, especially respiratory diseases, when compared to those in other occupations, including crop farmers, due to the time they spend in large animal confinement areas with poor air quality. 

Contribution to climate change

The impact of consuming animal products on climate change is well known, with meat and dairy accounting for 14.5% of global greenhouse gas emissions, according to the UN’s Food and Agriculture Organisation. Analysis of diets in the UK found that vegan diets resulted in 75% fewer emissions than the diets of high meat eaters and cut wildlife destruction and water use by 66% and 54%, respectively

A key reason that consuming animal products releases so many emissions is due to energy inefficiencies. A 2014 study estimated that if the crops currently produced for animal feed (and other non-food uses) were instead directly used for human consumption, this would create 70% more calories and could feed an additional 4 billion people. 

Quantifying the social costs of livestock and meat 

Various studies have quantified the healthcare costs attributable to meat consumption. Already in 1992, total healthcare costs, including NCD and foodborne illness, were estimated at between USD 28.6 billion and 61.4 billion. 

Research into designing a market-based approach to taxing meat according to its health impacts estimated that consumption of red and processed meat resulted in global healthcare costs totalling USD 285 billion as well as 2.4 million deaths in 2020, three-quarters of which were associated with processed meat consumption. This represents 0.3% of expected global GDP and 4.4% of expected deaths in that year. The researchers assessed that reducing meat intake through a meat tax could save an estimated 220,000 lives and reduce healthcare costs by USD 41 billion per year. 

If healthcare costs were included in the price of meat, processed meat would be 25% more expensive on average and over 100% more expensive in high-income countries. Similarly, red meat prices would increase by 4% on average, and over 20% in high-income countries. If factors like environmental impact and animal welfare were considered, the true cost of animal agriculture would likely be larger.

Adopting diets that meet recommended dietary guidelines would save USD 735 billion a year by 2050 in reduced health-related costs, with the savings increasing as more people switch to eating less meat and more plant-based diets. Following vegetarian diets would save USD 973 billion and vegan diets would save USD 1,067 billion. Around two-thirds of these savings are estimated to be due to reductions in direct healthcare-related costs. 

While many studies focus on the social cost of meat caused by the health impacts of consumption, some also consider the impacts of meat production. For example, in Italy, meat consumed generated a EUR 36.6 billion (USD 41 billion) cost to society in 2018. This was due to impacts from meat production and disease risk associated with consumption in equal measure. The study, undertaken in 2023, estimated that processed pork and beef generate the highest costs for society of the food groups assessed, at approximately EUR 2 (USD 2.2) per 100g. This was 8-20 times that of legumes, which provide a plant-based alternative to meat. 

At the global level, analysis estimates that a dietary shift away from animal-sourced foods could halve the externalities associated with food production and save up to USD 7.3 trillion in avoided health burden and ecosystem degradation costs associated with production, while cutting emissions. 

At the same time, 5.1 million deaths per year could be avoided if diets align with guidelines (up to 7.3 million deaths if vegetarian diets were implemented) and avoid a further USD 1.5 trillion in avoided climate damages due to associated emissions reductions by 2050, according to a 2016 study. 

  • 1
    This study is currently in pre-print.
  • 2
    USD figures are shown in 2025 values using XE currency converter on 16 April 2025.

Agroecological practices support climate change resilience

by Leave a Comment

Key points:

  • A number of meta-analyses, reviews and studies have compared the environmental and economic outcomes of agroecological practices compared to conventional agricultural practices.
  • There is a strong empirical evidence base for agroecology-aligned practices in supporting climate change adaptation, mitigation and resilience.
  • Benefits from agroecology practices include improved grain yields with fewer inputs, greater biodiversity, improved soil health and water security, and enhanced carbon sequestration.
  • Agroecology practices also reduce the need for pesticides and fossil-fuel-intensive synthetic fertilisers, reducing environmental risks as well as economic and health burdens for farmers.
  • Studies have also found that the concurrent application of more than one agroecological practice increases beneficial outcomes, with some finding that the positive outcomes increase with time.
  • While a number of agroecological benefits have been identified, the impacts are highly context-specific. Approaches will need to be tailored to the conditions of the region, ecosystem or farm.

What the science tells us about the benefits of agroecological practices

Agroecology emphasises the use of natural processes and resources to create sustainable and resilient agricultural systems. It is a response to modern intensive agricultural systems that focus on maximising production, sometimes at the expense of ecological and environmental health. A number of common agricultural practices are aligned with agroecology. For example, planting legumes alongside other crops – a centuries-old practice that is still widely used today – can improve soil fertility and water infiltration into the soil, thereby enhancing the health of the soil ecosystem and ultimately leading to increased crop yields.

Critics question the ability of agroecology to meet food security needs in a world that is increasingly at risk of climate change-induced threats that place pressure on natural systems, humans and economies.1David Zaruk, ‘Is Agroecology a Solution or an Agenda?’, Outlook on Agriculture 52, no. 3 (2023), https://doi.org/10.1177/00307270231191807. However, scientific support does exist for agroecological practices in enhancing resilience through energy efficiency, ecosystem services, food security and economic outcomes.

Through assessing more than 30 meta-analyses, seven second-order meta-analyses, and several reviews and field trials, this article summarises some of the ways by which agroecology-aligned practices can contribute to climate change resilience.

Yield and economic benefits with fewer inputs and emissions

One of the core tenets of agroecology is to reduce reliance on external inputs, such as synthetic fertilisers, pesticides and herbicides, in favour of practices that support biodiversity and soil health. As synthetic fertilisers are energy-intensive to produce and are typically made using fossil fuels, limiting their use can help reduce greenhouse gas emissions from agriculture. Synthetic fertilisers also contribute to nitrous oxide emissions – a potent greenhouse gas with significant ozone-depleting potential – once applied to the soil, with one study estimating that two thirds of emissions from synthetic fertilisers occur once they have been applied to the field.2Yunhu Gao and André Cabrera Serrenho, ‘Greenhouse Gas Emissions from Nitrogen Fertilizers Could Be Reduced by up to One-Fifth of Current Levels by 2050 with Combined Interventions’, Nature Food 4 (2023): 170–78, https://doi.org/10.1038/s43016-023-00698-w. Fertiliser application in conventional agriculture is excessive – nitrogen and phosphorus inputs are 60% and 48% higher than what major crops can use to grow – marking a clear space for agroecology-aligned principles in reducing emissions.3Paul C. West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, Science 345, no. 6194 (2014): 326, https://doi.org/10.1126/science.1246067.

Excessive chemical fertiliser application does not necessarily improve yields. For example, larger quantities of nitrogen or phosphorus fertiliser application did not have a positive effect on grain crop yields in a meta-analysis of more than 70 smallholder farms based in sub-Saharan Africa.4Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 449, https://doi.org/10.1038/s43016-020-0114-x. Rather, a positive effect was only noted at the lowest phosphorus fertiliser application rates of 0–20 kg P ha−1 and 20–40 kg P ha−1, while increasing the amount of fertiliser had negative effects on yield. Other estimates suggest that nitrogen and phosphorus application could be reduced by up to 29% and 22%, respectively, while maintaining current yields of wheat, rice and maize.5West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, 326. Reduced fertiliser inputs in agroecological systems also alleviate a major economic expense for farmers.6David Weisberger, Virginia Nichols, and Matt Liebman, ‘Does Diversifying Crop Rotations Suppress Weeds? A Meta-Analysis’, ed. Upendra M. Sainju, PLOS ONE 14, no. 7 (2019): e0219847, https://doi.org/10.1371/journal.pone.0219847. However, it is important to note that in certain areas, such as those with historically low fertiliser input levels, input reduction may not be appropriate.7Gatien N Falconnier et al., ‘The Input Reduction Principle of Agroecology Is Wrong When It Comes to Mineral Fertilizer Use in Sub-Saharan Africa’, Outlook on Agriculture 52, no. 3 (2023): 311–26, https://doi.org/10.1177/00307270231199795.

Shifting cropland systems towards agroforestry systems – whereby trees or shrubs are planted alongside crops or livestock – is a viable solution to addressing the leaky nitrogen cycle – whereby excess nitrogen is leaked into the environment or atmosphere, leading to emissions and water pollution, biodiversity loss and habitat degradation.8Ahmed S. Elrys et al., ‘Expanding Agroforestry Can Increase Nitrate Retention and Mitigate the Global Impact of a Leaky Nitrogen Cycle in Croplands’, Nature Food 4, no. 1 (2022): 109–21, https://doi.org/10.1038/s43016-022-00657-x. The consistent use of cover crops – which are crops that are not planted for immediate harvesting but rather because they offer some ecosystem benefit – can help reduce emissions from fertilisers by adding more nitrogen to the soil and reducing nitrate leaching. This limits the need for nitrogen application, with some analyses finding that cover cropping reduces nitrate leaching by up to 69% compared to fields left to fallow.9Richard Waite and Alex Rudee, ‘6 Ways the US Can Curb Climate Change and Grow More Food’, World Resources Institute, August 20, 2020, https://www.wri.org/insights/6-ways-us-can-curb-climate-change-and-grow-more-food. 10Amin Nouri et al., ‘When Do Cover Crops Reduce Nitrate Leaching? A Global Meta‐analysis’, Global Change Biology 28, no. 15 (2022): 4736–49, https://doi.org/10.1111/gcb.16269.

Multiple studies confirm that agroecological practices can improve crop yields with fewer inputs compared to conventional farming practices.11Sieglinde S. Snapp et al., ‘Biodiversity Can Support a Greener Revolution in Africa’, Proceedings of the National Academy of Sciences 107, no. 48 (2010): 20840–45, https://doi.org/10.1073/pnas.1007199107; Gudeta Sileshi et al., ‘Meta-Analysis of Maize Yield Response to Woody and Herbaceous Legumes in Sub-Saharan Africa’, Plant and Soil 307, no. 1–2 (2008): 1–19, https://doi.org/10.1007/s11104-008-9547-y; Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 447–54, https://doi.org/10.1038/s43016-020-0114-x; Shem Kuyah et al., ‘Agroforestry Delivers a Win-Win Solution for Ecosystem Services in Sub-Saharan Africa. A Meta-Analysis’, Agronomy for Sustainable Development 39, no. 5 (2019): 47, https://doi.org/10.1007/s13593-019-0589-8; Georges F. Félix et al., ‘Enhancing Agroecosystem Productivity with Woody Perennials in Semi-Arid West Africa. A Meta-Analysis’, Agronomy for Sustainable Development 38, no. 6 (2018): 57, https://doi.org/10.1007/s13593-018-0533-3. This is increasingly important as the effects of human-caused climate change, such as reduced rainfall, are anticipated to lower agricultural yields, thereby threatening food security. For example, a global systematic review of legume rotation – whereby staple crops are rotated with legumes – found a 20% increase in crop yields (rice, wheat and maize) on average compared to non-legume cropping systems.12Jie Zhao et al., ‘Global Systematic Review with Meta-Analysis Reveals Yield Advantage of Legume-Based Rotations and Its Drivers’, Nature Communications 13, no. 1 (2022): 4926, https://doi.org/10.1038/s41467-022-32464-0. In China, a long-term field experiment on the effects of intercropping – the simultaneous cultivation of two or more crops on one field – on grain yields found that yields were on average 22% higher than in comparable monoculture systems.13Xiao-Fei Li et al., ‘Long-Term Increased Grain Yield and Soil Fertility from Intercropping’, Nature Sustainability 4, no. 11 (2021): 943–50, https://doi.org/10.1038/s41893-021-00767-7. A review on the economic performance of agroecology in Europe found that agroecological farming generates incomes that exceed those of conventional agriculture, provides more employment per hectare, uses less fossil fuels and enhances biodiversity and landscapes.14Jan Douwe van der Ploeg et al., ‘The Economic Potential of Agroecology: Empirical Evidence from Europe’, Journal of Rural Studies 71 (2019): 46–61, https://doi.org/10.1016/j.jrurstud.2019.09.003.

A key finding of several of these studies is that the adoption of multiple agroecological practices maximises yield benefits over a single practice, and that these yield benefits tend to increase with time and are more stable year-to-year than in comparable conventional farming systems.

Improved ecosystem services, offering multiple benefits

Human-caused climate change is significantly impacting the provision of ecosystem services, defined as the benefits that humans derive from nature.15Yadvinder Malhi et al., ‘Climate Change and Ecosystems: Threats, Opportunities and Solutions’, Philosophical Transactions of the Royal Society B: Biological Sciences 375, no. 1794 (2020): 20190104, https://doi.org/10.1098/rstb.2019.0104. For example, changes in precipitation can lead to water scarcity, with knock-on effects for food production, or can lead to biodiversity loss, which would reduce the provision of various ecosystem services important for resilience. Studies show that farms with higher biodiversity show greater resilience to climate disasters.16Stacy M. Philpott et al., ‘A Multi-Scale Assessment of Hurricane Impacts on Agricultural Landscapes Based on Land Use and Topographic Features’, Agriculture, Ecosystems & Environment 128, no. 1–2 (2008): 12–20, https://doi.org/10.1016/j.agee.2008.04.016; Eric Holt-Giménez, ‘Measuring Farmers’ Agroecological Resistance after Hurricane Mitch in Nicaragua: A Case Study in Participatory, Sustainable Land Management Impact Monitoring’, Agriculture, Ecosystems & Environment 93, no. 1–3 (2002): 87–105, https://doi.org/10.1016/S0167-8809(02)00006-3. A number of studies from across the world have found that agroecological practices improve ecosystem services such as pollination, pest control, erosion, soil fertility and water management compared to conventional systems, and also enhance biodiversity.17Felipe Cozim-Melges et al., ‘Farming Practices to Enhance Biodiversity across Biomes: A Systematic Review’, npj Biodiversity 3, no. 1 (2024): 1, https://doi.org/10.1038/s44185-023-00034-2. 18Mario Torralba et al., ‘Do European Agroforestry Systems Enhance Biodiversity and Ecosystem Services? A Meta-Analysis’, Agriculture, Ecosystems & Environment 230 (2016): 150–61, https://doi.org/10.1016/j.agee.2016.06.002. 19Sara Palomo-Campesino, José A. González, and Marina García-Llorente, ‘Exploring the Connections between Agroecological Practices and Ecosystem Services: A Systematic Literature Review’, Sustainability 10, no. 12 (2018): 4339, https://doi.org/10.3390/su10124339. 20Matthew W. Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’, Forests 11, no. 12 (2020): 1321, https://doi.org/10.3390/f11121321. A third of the negative effects of landscape simplification – such as reduced provision of services and decreased crop production – were found to be due to decreased pollinator richness, emphasising the importance of practices that support pollinator diversity.21Matteo Dainese et al., ‘A Global Synthesis Reveals Biodiversity-Mediated Benefits for Crop Production’, SCIENCE ADVANCES, 2019, 4.

While conventional farming practices, such as intensive cultivation and pesticide use, are some of the biggest contributors to pollinator decline globally, agroecological practices increase the abundance and density of beneficial insects, reduce the abundance and density of insect pests, increase pollinator diversity, and reduce weed density and the abundance of parasitic and non-parasitic weeds.22Joseph Millard et al., ‘Global Effects of Land-Use Intensity on Local Pollinator Biodiversity’, Nature Communications 12, no. 1 (2021): 2902, https://doi.org/10.1038/s41467-021-23228-3. 23Charlie C. Nicholson et al., ‘Pesticide Use Negatively Affects Bumble Bees across European Landscapes’, Nature 628, no. 8007 (2024): 355–58, https://doi.org/10.1038/s41586-023-06773-3. 24Anjaharinony A.N.A. Rakotomalala, Anoush M. Ficiciyan, and Teja Tscharntke, ‘Intercropping Enhances Beneficial Arthropods and Controls Pests: A Systematic Review and Meta-Analysis’, Agriculture, Ecosystems & Environment 356 (2023): 108617, https://doi.org/10.1016/j.agee.2023.108617. 25Lorena Pumariño et al., ‘Effects of Agroforestry on Pest, Disease and Weed Control: A Meta-Analysis’, Basic and Applied Ecology 16, no. 7 (2015): 573–82, https://doi.org/10.1016/j.baae.2015.08.006. With pollination services globally valued at around USD 1 trillion, an abrupt pollinator collapse could cost around 1-2% of global GDP in the short term.26Christian Lippert, Arndt Feuerbacher, and Manuel Narjes, ‘Revisiting the Economic Valuation of Agricultural Losses Due to Large-Scale Changes in Pollinator Populations’, Ecological Economics 180 (2021): 106860, https://doi.org/10.1016/j.ecolecon.2020.106860.

Diversified farming systems, which are aligned with agroecology in that they incorporate different species or varieties rather than relying on single crops or species, in both high- and low-income countries are more profitable for farmers than conventional monoculture systems even when increased labour costs are considered, thereby dispelling myths that increased labour costs offset the benefits of diversification.27Andrea C. Sánchez et al., ‘Financial Profitability of Diversified Farming Systems: A Global Meta-Analysis’, Ecological Economics 201 (2022): 107595, https://doi.org/10.1016/j.ecolecon.2022.107595. In addition, diversification enhances biodiversity, pollination, pest control, nutrient cycling, soil fertility, and water regulation without compromising crop yields.28Giovanni Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, Science Advances 6, no. 45 (2020): eaba1715, https://doi.org/10.1126/sciadv.aba1715. Estimates for rice suggest that diversification can increase biodiversity by 40%, improve economic performance, such as incomes and profits, by 26% and reduce crop damage by 31% in global production.29Xueqing He et al., ‘Agricultural Diversification Promotes Sustainable and Resilient Global Rice Production’, Nature Food 4, no. 9 (2023): 788–96, https://doi.org/10.1038/s43016-023-00836-4.

Diversification practices deliver multiple benefits relating to ecosystem services without compromising yield, highlighting that mainstream, high-yielding agricultural systems can benefit from diversification practices and that these practices can help bolster future sustainable food production.30Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, 4.

Agroecological practices can also significantly decrease soil erosion – the most important indicator of land degradation – in temperate, tropical and mediterranean-type soils.31Mbezele Junior Yannick Ngaba et al., ‘Meta-Analysis Unveils Differential Effects of Agroforestry on Soil Properties in Different Zonobiomes’, Plant and Soil 496, no. 1–2 (2024): 589–607, https://doi.org/10.1007/s11104-023-06385-w. A systematic evidence map of temperate agroforestry on sheep and cattle productivity, environmental impacts and economics found that temperate agroforestry offers benefits compared to pasture without trees through sequestering carbon, reducing soil erosion, and improving water quantity and quality regulation.32Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’. There is also some evidence, albeit limited, that agroecological practices can improve livestock productivity.33Paulo César De Faccio Carvalho et al., ‘Land-Use Intensification Trends in the Rio De La Plata Region of South America: Toward Specialization or Recoupling Crop and Livestock Production’, Frontiers of Agricultural Science and Engineering 8, no. 1 (2021): 97, https://doi.org/10.15302/J-FASE-2020380. 34Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’.

Enhanced food security and health

As food systems are highly vulnerable to climate risks, improving resilience to these risks is important for ensuring food security. There is empirical evidence for agroecological practices such as livestock integration, intercropping, crop diversification, organic manure application and agroforestry in improving food security and resilience.35Gilbert Dagunga et al., ‘Agroecology and Resilience of Smallholder Food Security: A Systematic Review’, Frontiers in Sustainable Food Systems 7 (2023): 1267630, https://doi.org/10.3389/fsufs.2023.1267630. A 2024 review found that livestock diversification, soil conservation and non-crop diversification – practices not recognised as traditional crop production, such as the planting of hedgerows – improved food security in an assessment of 2,655 farms, and that a combination of these practices yielded greater improvements than they achieved singularly.36Laura Vang Rasmussen et al., ‘Joint Environmental and Social Benefits from Diversified Agriculture’, Science 384, no. 6691 (2024): 87–93, https://doi.org/10.1126/science.adj1914. A number of studies on the potential for agroecology to improve food security and nutrition have found that the number of agroecological practices implemented on a farm was positively associated with better food security and nutrition outcomes.

The demand for protein is projected to increase in the future, placing further demands on land and resources. Animal protein is an important source of nutrition, meaning a balance will need to be stuck between nutritional and environmental needs.37Maeve Henchion et al., ‘Future Protein Supply and Demand: Strategies and Factors Influencing a Sustainable Equilibrium’, Foods 6, no. 7 (2017): 53, https://doi.org/10.3390/foods6070053. A review on whether agroecology can help meet protein requirements for 2050 estimated that using an agroecological model where livestock are fed only on pasture, waste or by-products – and never fed on human-edible crops – can achieve a global diet within a limitation of 11–23 grams of protein per day from animal products.38Georgia Forsyth Sijpestijn, Alexander Wezel, and Sghaier Chriki, ‘Can Agroecology Help in Meeting Our 2050 Protein Requirements?’, Livestock Science 256 (2022): 104822, https://doi.org/10.1016/j.livsci.2022.104822.

The adoption of agroecological principles can help alleviate disease costs associated with pesticide exposure. Pesticides have been linked to ​​diabetes, reproductive disorders, neurological dysfunction, cancer and respiratory disorders in farmers.39Lata Rani et al., ‘An Extensive Review on the Consequences of Chemical Pesticides on Human Health and Environment’, Journal of Cleaner Production 283 (2021): 124657, https://doi.org/10.1016/j.jclepro.2020.124657. A meta-analysis found a link between mental illnesses such as depression and pesticide exposure in farmers, with affected farmers experiencing financial difficulties and poor health.40Mariane Magalhães Zanchi, Katiuska Marins, and Ariane Zamoner, ‘Could Pesticide Exposure Be Implicated in the High Incidence Rates of Depression, Anxiety and Suicide in Farmers? A Systematic Review’, Environmental Pollution 331 (2023): 121888, https://doi.org/10.1016/j.envpol.2023.121888. For the general public, the annual health and disease costs of exposure to organophosphate pesticides in 2010 were estimated at USD 121 billion in Europe and USD 42 billion in the US.41Teresa M Attina et al., ‘Exposure to Endocrine-Disrupting Chemicals in the USA: A Population-Based Disease Burden and Cost Analysis’, The Lancet Diabetes & Endocrinology 4, no. 12 (2016): 996–1003, https://doi.org/10.1016/S2213-8587(16)30275-3. Exposure to pesticides in Europe in 2003 was estimated to cause an average burden of lifetime lost per person of 2.6 hours and up to 45.3 days, and average costs per person over lifetime of EUR 12 and up to EUR 5,142.42Peter Fantke, Rainer Friedrich, and Olivier Jolliet, ‘Health Impact and Damage Cost Assessment of Pesticides in Europe’, Environment International 49 (2012): 9–17, https://doi.org/10.1016/j.envint.2012.08.001. In addition, as pollinators are directly responsible for up to 40% of the world’s micronutrient supply, including essential micronutrients such as vitamin A, pollinator collapse could result in 1.42 million additional deaths per year from non-communicable and malnutrition-related diseases, and 27 million lost disability-adjusted life-years annually at the global scale.43Matthew R Smith et al., ‘Effects of Decreases of Animal Pollinators on Human Nutrition and Global Health: A Modelling Analysis’, The Lancet 386, no. 10007 (2015): 1964–72, https://doi.org/10.1016/S0140-6736(15)61085-6.

Sequestration in plants and soil can help meet Nationally Determined Contributions

Estimates suggest that agroforestry can sequester 0.12 to 0.31 gigatons of carbon (Gt C) per year, making it comparable to other nature-based solutions such as reforestation (0.27 Gt C per year) and reduced deforestation (0.49 Gt C per year).44Drew E. Terasaki Hart et al., ‘Priority Science Can Accelerate Agroforestry as a Natural Climate Solution’, Nature Climate Change 13, no. 11 (2023): 1179, https://doi.org/10.1038/s41558-023-01810-5. Agroforestry has also been identified as a key intervention for achieving Nationally Determined Contributions (NDCs). A 2023 review looked at the extent to which agroforestry is represented in current NDCs in 22 developing countries and found that more than 80% of countries that experienced deforestation between 2000 and 2015 could meet their unconditional NDC targets by converting 25% of deforested lands to agroforestry.45Jagdish Chander Dagar, Sharda Rani Gupta, and Gudeta Weldesemayat Sileshi, eds., Agroforestry for Sustainable Intensification of Agriculture in Asia and Africa, Sustainability Sciences in Asia and Africa (Singapore: Springer Nature Singapore, 2023), https://doi.org/10.1007/978-981-19-4602-8. Integrating agroecological practices into countries’

National Biodiversity Strategies and Action Plans (NBSAPs) can also help fulfill Global Biodiversity Framework (GBF) commitments by encouraging the use of sustainable practices that protect biodiversity, build climate resilience and enhance food security.46‘FAOLEX Database’, Food and Agriculture Organization of the United Nations, 2023.

A literature review on soil carbon sequestration in the context of climate change found that agroecological practices such as the incorporation of organic matter into the soil, crop rotation and the use of cover crops can improve soil carbon sequestration.47Cristina I. Dias Rodrigues, Luís Miguel Brito, and Leonel J. R. Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation: A Review’, Soil Systems 7, no. 3 (2023): 64, https://doi.org/10.3390/soilsystems7030064. One analysis suggests that increasing the soil organic carbon pool of degraded croplands using agroecological practices has the potential to increase yields of wheat by 20-40 kg per hectare, maize yields by 10-20 kg per hectare and cowpea yields by 0.5-1 kg per hectare.48R. Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’, Science 304, no. 5677 (2004): 1623–27, https://doi.org/10.1126/science.1097396. The analysis also suggests that this approach can offset fossil fuel emissions by 0.4-1.2 Gt C per year, which is as much as 3% of current global fossil fuel emissions. Other estimates suggest that improved cropland management using agroecological principles could mitigate around 1.4–2.3 Gt carbon dioxide equivalent per year (CO2eq/year), while improved grazing management could mitigate 1.4–1.8 Gt CO2eq/year.49Pete Smith et al., ‘Which Practices Co‐deliver Food Security, Climate Change Mitigation and Adaptation, and Combat Land Degradation and Desertification?’, Global Change Biology 26, no. 3 (2020): 1532–75, https://doi.org/10.1111/gcb.14878.

The potential for sequestration will be highly context-specific, and the possible reversal of sequestration benefits remains an important limiting factor, especially for soil carbon.50Cécile M. Godde et al., ‘Soil Carbon Sequestration in Grazing Systems: Managing Expectations’, Climatic Change 161, no. 3 (2020): 385–91, https://doi.org/10.1007/s10584-020-02673-x. Carbon sequestered in the soil can be retained for as long as agroecological practices are maintained and with minimal disturbance to the soil, thereby helping to address issues around the permanence of the sequestered carbon.51Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’. The consistent application of sustainable management practices is important for realising the mitigation benefits of soil and plant carbon sequestration.52Rodrigues, Brito, and Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation’.

  • 1
    David Zaruk, ‘Is Agroecology a Solution or an Agenda?’, Outlook on Agriculture 52, no. 3 (2023), https://doi.org/10.1177/00307270231191807.
  • 2
    Yunhu Gao and André Cabrera Serrenho, ‘Greenhouse Gas Emissions from Nitrogen Fertilizers Could Be Reduced by up to One-Fifth of Current Levels by 2050 with Combined Interventions’, Nature Food 4 (2023): 170–78, https://doi.org/10.1038/s43016-023-00698-w.
  • 3
    Paul C. West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, Science 345, no. 6194 (2014): 326, https://doi.org/10.1126/science.1246067.
  • 4
    Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 449, https://doi.org/10.1038/s43016-020-0114-x.
  • 5
    West et al., ‘Leverage Points for Improving Global Food Security and the Environment’, 326.
  • 6
    David Weisberger, Virginia Nichols, and Matt Liebman, ‘Does Diversifying Crop Rotations Suppress Weeds? A Meta-Analysis’, ed. Upendra M. Sainju, PLOS ONE 14, no. 7 (2019): e0219847, https://doi.org/10.1371/journal.pone.0219847.
  • 7
    Gatien N Falconnier et al., ‘The Input Reduction Principle of Agroecology Is Wrong When It Comes to Mineral Fertilizer Use in Sub-Saharan Africa’, Outlook on Agriculture 52, no. 3 (2023): 311–26, https://doi.org/10.1177/00307270231199795.
  • 8
    Ahmed S. Elrys et al., ‘Expanding Agroforestry Can Increase Nitrate Retention and Mitigate the Global Impact of a Leaky Nitrogen Cycle in Croplands’, Nature Food 4, no. 1 (2022): 109–21, https://doi.org/10.1038/s43016-022-00657-x.
  • 9
    Richard Waite and Alex Rudee, ‘6 Ways the US Can Curb Climate Change and Grow More Food’, World Resources Institute, August 20, 2020, https://www.wri.org/insights/6-ways-us-can-curb-climate-change-and-grow-more-food.
  • 10
    Amin Nouri et al., ‘When Do Cover Crops Reduce Nitrate Leaching? A Global Meta‐analysis’, Global Change Biology 28, no. 15 (2022): 4736–49, https://doi.org/10.1111/gcb.16269.
  • 11
    Sieglinde S. Snapp et al., ‘Biodiversity Can Support a Greener Revolution in Africa’, Proceedings of the National Academy of Sciences 107, no. 48 (2010): 20840–45, https://doi.org/10.1073/pnas.1007199107; Gudeta Sileshi et al., ‘Meta-Analysis of Maize Yield Response to Woody and Herbaceous Legumes in Sub-Saharan Africa’, Plant and Soil 307, no. 1–2 (2008): 1–19, https://doi.org/10.1007/s11104-008-9547-y; Marc Corbeels et al., ‘Limits of Conservation Agriculture to Overcome Low Crop Yields in Sub-Saharan Africa’, Nature Food 1, no. 7 (2020): 447–54, https://doi.org/10.1038/s43016-020-0114-x; Shem Kuyah et al., ‘Agroforestry Delivers a Win-Win Solution for Ecosystem Services in Sub-Saharan Africa. A Meta-Analysis’, Agronomy for Sustainable Development 39, no. 5 (2019): 47, https://doi.org/10.1007/s13593-019-0589-8; Georges F. Félix et al., ‘Enhancing Agroecosystem Productivity with Woody Perennials in Semi-Arid West Africa. A Meta-Analysis’, Agronomy for Sustainable Development 38, no. 6 (2018): 57, https://doi.org/10.1007/s13593-018-0533-3.
  • 12
    Jie Zhao et al., ‘Global Systematic Review with Meta-Analysis Reveals Yield Advantage of Legume-Based Rotations and Its Drivers’, Nature Communications 13, no. 1 (2022): 4926, https://doi.org/10.1038/s41467-022-32464-0.
  • 13
    Xiao-Fei Li et al., ‘Long-Term Increased Grain Yield and Soil Fertility from Intercropping’, Nature Sustainability 4, no. 11 (2021): 943–50, https://doi.org/10.1038/s41893-021-00767-7.
  • 14
    Jan Douwe van der Ploeg et al., ‘The Economic Potential of Agroecology: Empirical Evidence from Europe’, Journal of Rural Studies 71 (2019): 46–61, https://doi.org/10.1016/j.jrurstud.2019.09.003.
  • 15
    Yadvinder Malhi et al., ‘Climate Change and Ecosystems: Threats, Opportunities and Solutions’, Philosophical Transactions of the Royal Society B: Biological Sciences 375, no. 1794 (2020): 20190104, https://doi.org/10.1098/rstb.2019.0104.
  • 16
    Stacy M. Philpott et al., ‘A Multi-Scale Assessment of Hurricane Impacts on Agricultural Landscapes Based on Land Use and Topographic Features’, Agriculture, Ecosystems & Environment 128, no. 1–2 (2008): 12–20, https://doi.org/10.1016/j.agee.2008.04.016; Eric Holt-Giménez, ‘Measuring Farmers’ Agroecological Resistance after Hurricane Mitch in Nicaragua: A Case Study in Participatory, Sustainable Land Management Impact Monitoring’, Agriculture, Ecosystems & Environment 93, no. 1–3 (2002): 87–105, https://doi.org/10.1016/S0167-8809(02)00006-3.
  • 17
    Felipe Cozim-Melges et al., ‘Farming Practices to Enhance Biodiversity across Biomes: A Systematic Review’, npj Biodiversity 3, no. 1 (2024): 1, https://doi.org/10.1038/s44185-023-00034-2.
  • 18
    Mario Torralba et al., ‘Do European Agroforestry Systems Enhance Biodiversity and Ecosystem Services? A Meta-Analysis’, Agriculture, Ecosystems & Environment 230 (2016): 150–61, https://doi.org/10.1016/j.agee.2016.06.002.
  • 19
    Sara Palomo-Campesino, José A. González, and Marina García-Llorente, ‘Exploring the Connections between Agroecological Practices and Ecosystem Services: A Systematic Literature Review’, Sustainability 10, no. 12 (2018): 4339, https://doi.org/10.3390/su10124339.
  • 20
    Matthew W. Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’, Forests 11, no. 12 (2020): 1321, https://doi.org/10.3390/f11121321.
  • 21
    Matteo Dainese et al., ‘A Global Synthesis Reveals Biodiversity-Mediated Benefits for Crop Production’, SCIENCE ADVANCES, 2019, 4.
  • 22
    Joseph Millard et al., ‘Global Effects of Land-Use Intensity on Local Pollinator Biodiversity’, Nature Communications 12, no. 1 (2021): 2902, https://doi.org/10.1038/s41467-021-23228-3.
  • 23
    Charlie C. Nicholson et al., ‘Pesticide Use Negatively Affects Bumble Bees across European Landscapes’, Nature 628, no. 8007 (2024): 355–58, https://doi.org/10.1038/s41586-023-06773-3.
  • 24
    Anjaharinony A.N.A. Rakotomalala, Anoush M. Ficiciyan, and Teja Tscharntke, ‘Intercropping Enhances Beneficial Arthropods and Controls Pests: A Systematic Review and Meta-Analysis’, Agriculture, Ecosystems & Environment 356 (2023): 108617, https://doi.org/10.1016/j.agee.2023.108617.
  • 25
    Lorena Pumariño et al., ‘Effects of Agroforestry on Pest, Disease and Weed Control: A Meta-Analysis’, Basic and Applied Ecology 16, no. 7 (2015): 573–82, https://doi.org/10.1016/j.baae.2015.08.006.
  • 26
    Christian Lippert, Arndt Feuerbacher, and Manuel Narjes, ‘Revisiting the Economic Valuation of Agricultural Losses Due to Large-Scale Changes in Pollinator Populations’, Ecological Economics 180 (2021): 106860, https://doi.org/10.1016/j.ecolecon.2020.106860.
  • 27
    Andrea C. Sánchez et al., ‘Financial Profitability of Diversified Farming Systems: A Global Meta-Analysis’, Ecological Economics 201 (2022): 107595, https://doi.org/10.1016/j.ecolecon.2022.107595.
  • 28
    Giovanni Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, Science Advances 6, no. 45 (2020): eaba1715, https://doi.org/10.1126/sciadv.aba1715.
  • 29
    Xueqing He et al., ‘Agricultural Diversification Promotes Sustainable and Resilient Global Rice Production’, Nature Food 4, no. 9 (2023): 788–96, https://doi.org/10.1038/s43016-023-00836-4.
  • 30
    Tamburini et al., ‘Agricultural Diversification Promotes Multiple Ecosystem Services without Compromising Yield’, 4.
  • 31
    Mbezele Junior Yannick Ngaba et al., ‘Meta-Analysis Unveils Differential Effects of Agroforestry on Soil Properties in Different Zonobiomes’, Plant and Soil 496, no. 1–2 (2024): 589–607, https://doi.org/10.1007/s11104-023-06385-w.
  • 32
    Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’.
  • 33
    Paulo César De Faccio Carvalho et al., ‘Land-Use Intensification Trends in the Rio De La Plata Region of South America: Toward Specialization or Recoupling Crop and Livestock Production’, Frontiers of Agricultural Science and Engineering 8, no. 1 (2021): 97, https://doi.org/10.15302/J-FASE-2020380.
  • 34
    Jordon et al., ‘Implications of Temperate Agroforestry on Sheep and Cattle Productivity, Environmental Impacts and Enterprise Economics. A Systematic Evidence Map’.
  • 35
    Gilbert Dagunga et al., ‘Agroecology and Resilience of Smallholder Food Security: A Systematic Review’, Frontiers in Sustainable Food Systems 7 (2023): 1267630, https://doi.org/10.3389/fsufs.2023.1267630.
  • 36
    Laura Vang Rasmussen et al., ‘Joint Environmental and Social Benefits from Diversified Agriculture’, Science 384, no. 6691 (2024): 87–93, https://doi.org/10.1126/science.adj1914.
  • 37
    Maeve Henchion et al., ‘Future Protein Supply and Demand: Strategies and Factors Influencing a Sustainable Equilibrium’, Foods 6, no. 7 (2017): 53, https://doi.org/10.3390/foods6070053.
  • 38
    Georgia Forsyth Sijpestijn, Alexander Wezel, and Sghaier Chriki, ‘Can Agroecology Help in Meeting Our 2050 Protein Requirements?’, Livestock Science 256 (2022): 104822, https://doi.org/10.1016/j.livsci.2022.104822.
  • 39
    Lata Rani et al., ‘An Extensive Review on the Consequences of Chemical Pesticides on Human Health and Environment’, Journal of Cleaner Production 283 (2021): 124657, https://doi.org/10.1016/j.jclepro.2020.124657.
  • 40
    Mariane Magalhães Zanchi, Katiuska Marins, and Ariane Zamoner, ‘Could Pesticide Exposure Be Implicated in the High Incidence Rates of Depression, Anxiety and Suicide in Farmers? A Systematic Review’, Environmental Pollution 331 (2023): 121888, https://doi.org/10.1016/j.envpol.2023.121888.
  • 41
    Teresa M Attina et al., ‘Exposure to Endocrine-Disrupting Chemicals in the USA: A Population-Based Disease Burden and Cost Analysis’, The Lancet Diabetes & Endocrinology 4, no. 12 (2016): 996–1003, https://doi.org/10.1016/S2213-8587(16)30275-3.
  • 42
    Peter Fantke, Rainer Friedrich, and Olivier Jolliet, ‘Health Impact and Damage Cost Assessment of Pesticides in Europe’, Environment International 49 (2012): 9–17, https://doi.org/10.1016/j.envint.2012.08.001.
  • 43
    Matthew R Smith et al., ‘Effects of Decreases of Animal Pollinators on Human Nutrition and Global Health: A Modelling Analysis’, The Lancet 386, no. 10007 (2015): 1964–72, https://doi.org/10.1016/S0140-6736(15)61085-6.
  • 44
    Drew E. Terasaki Hart et al., ‘Priority Science Can Accelerate Agroforestry as a Natural Climate Solution’, Nature Climate Change 13, no. 11 (2023): 1179, https://doi.org/10.1038/s41558-023-01810-5.
  • 45
    Jagdish Chander Dagar, Sharda Rani Gupta, and Gudeta Weldesemayat Sileshi, eds., Agroforestry for Sustainable Intensification of Agriculture in Asia and Africa, Sustainability Sciences in Asia and Africa (Singapore: Springer Nature Singapore, 2023), https://doi.org/10.1007/978-981-19-4602-8.
  • 46
    ‘FAOLEX Database’, Food and Agriculture Organization of the United Nations, 2023.
  • 47
    Cristina I. Dias Rodrigues, Luís Miguel Brito, and Leonel J. R. Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation: A Review’, Soil Systems 7, no. 3 (2023): 64, https://doi.org/10.3390/soilsystems7030064.
  • 48
    R. Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’, Science 304, no. 5677 (2004): 1623–27, https://doi.org/10.1126/science.1097396.
  • 49
    Pete Smith et al., ‘Which Practices Co‐deliver Food Security, Climate Change Mitigation and Adaptation, and Combat Land Degradation and Desertification?’, Global Change Biology 26, no. 3 (2020): 1532–75, https://doi.org/10.1111/gcb.14878.
  • 50
    Cécile M. Godde et al., ‘Soil Carbon Sequestration in Grazing Systems: Managing Expectations’, Climatic Change 161, no. 3 (2020): 385–91, https://doi.org/10.1007/s10584-020-02673-x.
  • 51
    Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’.
  • 52
    Rodrigues, Brito, and Nunes, ‘Soil Carbon Sequestration in the Context of Climate Change Mitigation’.

Relying on soil-based carbon capture to offset livestock emissions is risky

by Leave a Comment

Key points:

  • Soil carbon sequestration is the process through which atmospheric carbon dioxide is captured and stored in soil, forming part of the natural global carbon cycle.
  • In undisturbed natural ecosystems, carbon may be stored in the soil for thousands of years. However, the conversion of natural land into farmland has depleted soil organic carbon stocks and released this stored carbon into the atmosphere.
  • Livestock grazing systems are responsible for the loss of significant amounts of soil carbon over the past six decades.
  • Regenerative grazing – which involves rotating livestock on land for short durations – has been proposed as a solution for improving soil carbon stocks and offsetting emissions from livestock farming.
  • Recent estimates suggest that improved grazing management could potentially take-up around 63  gigatons (billion metric tons) of carbon in vegetation and soils.
  • However, once methane and nitrous oxide emissions from grazing animals are considered, an estimated 135 gigatons of carbon take-up would be needed to offset these emissions.
  • Relying on soil carbon sequestration to offset emissions from grazing systems is risky as carbon storage is finite and reversible, and increased emissions of methane and nitrous oxide could offset any gains from carbon sequestered in the soil. The impacts of regenerative grazing are also highly context-dependent.
  • Despite uncertainties, sequestering carbon in soil could contribute to climate change mitigation in the medium term in certain regions of the world.
  • Management practices aimed at maintaining or improving soil carbon offer other benefits, such as improved soil health, erosion control and reduced emissions intensity, with positive outcomes for yields and farmers’ incomes.


Soil carbon sequestration: the basics

Soil carbon sequestration is the process through which atmospheric carbon dioxide is captured and stored in soil. Plants capture atmospheric carbon dioxide through photosynthesis, and the carbon is stored in its organic form in plant tissues while the oxygen is released back into the atmosphere. As the leaves, roots and other tissues of plants decay, the carbon contained in these tissues is released into the soil through microbial activity, enriching the soil carbon pool. The carbon pool is also enriched through the exchange of carbon between plant roots and soil microbes.

Soil carbon sequestration is a natural process that forms a critical part of the global carbon cycle – whereby carbon is exchanged among all life on earth, the soil, water, minerals and the atmosphere. Soil organic carbon is important because it regulates the functioning of ecosystems, provides energy for soil microorganisms and improves the structure of soil. It is also an important carbon sink – the soil organic carbon pool contains up to 2,400 gigatons (or billion metric tons) of carbon, which is more than double that of the atmospheric carbon pool.

In undisturbed natural ecosystems, carbon may be stored in the soil for thousands of years. However, the conversion of natural land into agricultural land from human activities has depleted soil organic carbon stocks by reducing the amount of plant tissues in soil and encouraging erosion, thereby destroying soil structure and speeding up microbial breakdown. It is estimated that over the last 15,000 years, and particularly in the last 200 years, the growth of farmland has released 133 gigatons of carbon from the top two metres of the soil layer. This is equivalent to about 80 years’ worth of present-day US emissions.

This deficit of soil organic carbon has created an opportunity to draw earth-warming carbon dioxide from the atmosphere and store it in the soil in an effort to mitigate against climate change.

Grazing systems and soil organic carbon

Grasslands are a significant reservoir of soil carbon, storing around one-third of the global soil organic carbon pool.1This definition of grasslands includes some savannas, woodlands, shrublands and tundra. However, estimates suggest that livestock grazing is responsible for the loss of 46 gigatons of soil carbon over the past six decades – which is more than four years’ worth of current global fossil fuel emissions.

While moderate to heavy livestock grazing depletes the soil organic carbon pool on average, light grazing has been found to increase soil organic carbon stocks. This is because grazing can stimulate plant productivity and the allocation of carbon to the roots for microbes, thereby increasing carbon sequestration.2Some studies show that grazing-induced changes in vegetation are not correlated with changes in soil organic carbon. As a consequence, ‘regenerative grazing’ – which involves rotating livestock on land for short durations to allow soil to recover and draw carbon dioxide from the atmosphere – has been proposed as a solution for improving soil carbon stocks and mitigating the climate change impacts of livestock grazing. Currently, global grazing systems emit more greenhouse gases than they sequester.

A 2021 analysis found that ‘adaptive multi-paddock grazing’ – a form of regenerative grazing – increased soil carbon stocks compared to conventional grazing. The authors emphasised the importance of carbon being stored in the mineral fraction of the soil – meaning it is tightly bound to soil particles. This makes the sequestered carbon more resistant to disturbance and means it will be stored for a longer duration. The study is backed by a global meta-analysis, which found that regenerative practices, particularly integrated crop-livestock systems, have significant potential to increase soil organic carbon pools because they enhance the storage of carbon in the mineral soil fraction.

Another study reported that over a four-year period, the emissions from adaptive multi-paddock grazing on a beef farm could be completely offset by the carbon sequestered in the soil. Some advocates of regenerative grazing have gone as far as claiming it can ‘reverse climate change’. They argue that increasing livestock production could help sequester more carbon from the atmosphere into the soil.3This is in contrast to experts who believe that managing livestock numbers will be essential, together with other strategies, for reaching Paris Agreement commitments.

A long-term field experiment found that rotational grazing accumulated more soil organic carbon than other management systems. However, the findings have been questioned by other scientists, who point out that the analysis did not consider the contribution of methane and nitrous oxide – two significant greenhouse gases associated with livestock farming – and the method for measuring the permanence of soil carbon was unsuitable. According to these scientists, “grazing cattle, well-managed or not, has no role in enhanced C sequestration.”

How much carbon could these strategies sequester?

An analysis published this year estimates that improved grazing management could take-up around 63 gigatons of carbon in vegetation and soils globally. This number is three times higher than IPCC estimates, which the authors attribute to the overly simplistic model used by the IPCC. To put the number into perspective, 63 gigatons is about six years’ worth of emissions from fossil fuels globally.

A separate analysis published in 2022 suggests that 148 to 699 megatons (or million metric tons) of carbon dioxide equivalent could be sequestered in the soil globally every year through improved grazing management.4Other estimates suggest that improved grazing management could sequester 0.28 megatons of carbon per hectare per year.

Sequestration potential overstated

Some scientists are more cautious and suggest that the potential for soil carbon sequestration under regenerative agriculture to offset emissions may be greatly overestimated. There are several reasons why relying on soil carbon sequestration to offset emissions from livestock systems is risky.

1. The capacity for soil to store carbon is finite

In long-term undisturbed ecosystems, soil carbon stocks are assumed to be equal to soil carbon emissions because the system has reached a state of equilibrium, or a steady state. When the ecosystem is disturbed – such as a grassland being overstocked with cattle – carbon is released from the soil due to, for example, erosion from reduced vegetation cover. Once a new land management practice aimed at enhancing soil carbon sequestration – such as rotational grazing – is introduced on this disturbed land, the rate of soil carbon sequestration follows a sigmoid curve, being high during the initial period after adoption of the practice and then slowing down upon approaching a new soil carbon steady state (Figure 1).

Figure 1. Soil carbon sequestration after a new management practice is introduced
Note: Figure has been adapted from Considering the influence of sequestration duration and carbon saturation on estimates of soil carbon capacity, 2006. The graph is theoretical and the axes are not true to scale.

The new steady state reflects a balance between carbon inputs and outputs under the new management practice, with soil carbon stocks no longer increasing. For grassland management, estimates suggest that the time until the maximum sequestration is reached is, on average, around five years, with declining rates for another 45 years. In other words, the rate of carbon sequestered within the first several years of a new practice being introduced does not reflect the long-term total sequestration rate.

Initial soil carbon sequestration rates from short-term studies on regenerative grazing should therefore not be extrapolated to estimate the total soil carbon sequestration potential of the practice. In some cases, the carbon sequestration potential can be improved beyond the new steady state with the addition of inputs, such as manure.5Importantly, inputs such as manure can also increase the emissions of other greenhouse gases, offsetting soil carbon sequestration gains. Soil carbon saturation then occurs when further inputs no longer lead to increased carbon stores, representing a cap on the carbon storage capacity.6Estimates suggest that saturation is reached at 82 g C kg-1 silt+clay for 2:1 clay dominated soils and 46 g C kg-1 silt+clay for 1:1 clay dominated soils.

2. Soil carbon storage is reversible

For the sequestered carbon to remain in the soil, and for the rate of sequestration to reach its full potential, the new practice needs to be implemented permanently. However, disturbances such as fires or floods – which can be difficult to predict and control – could reverse the practice and cause the release of stored carbon. Climate change is contributing to this reversibility, causing the release of decades-old soil organic carbon by thawing permafrost and accelerating microbial decomposition. This creates a positive feedback loop that further accelerates global warming. As soil organic carbon is sensitive to temperature changes, it is estimated that the potential storage capacity could decrease by 14% by 2040 under a moderate global warming pathway.7The SSP3−7.0 pathway from CMIP6.

3. Warming potential of other greenhouse gases

Land management changes that enhance soil carbon sequestration may increase the emissions of other, more potent, greenhouse gases. In certain cases, even small increases in these other gases may offset the benefit from the change in soil carbon stocks offered by the practice. Ruminant (cows, buffaloes, sheep and goats) farming emits nitrous oxide (from manure), which has a global warming potential 265 times that of carbon dioxide, and methane (from belching animals), which has a warming potential 28 times that of carbon dioxide. They are both also shorter-lived gases than carbon dioxide and have a stronger initial warming effect. Estimates suggest that ruminants emit 110 megatons of methane and 2.4 megatons of nitrous oxide every year, in addition to carbon dioxide.8The ratio of emitted methane: carbon dioxide in ruminants is 4:1. Studies claiming regenerative grazing systems have a net benefit have been criticised for failing to consider the warming contributions of these gases.

A 2023 study estimated the potential for ruminant emissions to be offset through soil carbon sequestration in grasslands, considering the different warming potentials and lifespans of these greenhouse gases. The analysis suggests that around 135 gigatonnes of carbon would need to be sequestered in order to offset global methane and nitrous oxide emissions from ruminant farming – more than double the carbon sequestration potential of improved grazing management. For some grasslands, the soil carbon stock would need to increase by up to 2,000%, which emphasises how infeasible grassland management might be for offsetting ruminant emissions once the warming from other gases is considered.

4. Context is important

Though moderate to heavy grazing consistently reduces soil carbon stocks on average on a global scale, the impacts are highly context-dependent and will vary depending on a number of factors such as the climate conditions, type of soil, type of grazer, the vegetation type and the grazing strategy used. For example, sheep have a greater negative impact on soil carbon sequestration than cattle; the impacts of a higher grazing intensity will be more severe in warmer climates but less severe when water availability is high; and certain types of grasses will improve carbon sequestration, even under heavy grazing.

Due to this wide variability, some scientists argue that it is difficult to anticipate the soil sequestration potential of regenerative grazing practices. There are also concerns that farmers’ skills and motivation levels could limit the outcomes and scalability of practices. Difficulties in measuring the results also makes monitoring soil carbon stocks challenging – it typically takes a decade of monitoring to determine how much carbon a practice is sequestering.

Soil carbon markets

Through soil carbon markets or ‘carbon farming’, farmers implement a management practice that allows them to sell ‘carbon credits’. The credits, a quantifiable amount of carbon dioxide that has been sequestered in the soil from the management practice, are being proposed as a solution to mitigate climate change, with millions of dollars’ worth of credits already sold. However, the uncertainties around the permanence, monitoring and accounting of soil carbon make soil carbon certificates unsuitable for climate change mitigation.9While permanence is a necessary condition for creditable carbon offsets – which are typically issued over a 100-year period – this permanence refers to the duration for which the sequestration practice is carried out rather than the stored soil carbon. Therefore, when the practice ends and the carbon is lost to the atmosphere, it is no longer a permanent removal. As emphasised by a prominent soil scientist, “It’s really hard to evaluate the actual greenhouse gas benefit of these programs”.

Sequestration offers important benefits

Despite several limitations, sequestering carbon in soil could make a meaningful contribution to climate change mitigation in the medium term in certain regions of the world, depending on the management strategy that is used. For example, converting arable land to grassland or forest will almost always have a positive effect on soil carbon sequestration. In addition, many management strategies are well-established and are not reliant on the development of new technologies, meaning they can be implemented quickly and with relative ease.

Additionally, management practices aimed at maintaining or improving soil carbon typically offer multiple other benefits, such as improved soil health, erosion control, increased water availability and reduced emissions intensity, with positive outcomes for yields and farmers’ incomes.

The effectiveness of animal feed supplements in cutting methane emissions

by Leave a Comment

Key points:

  • Various natural and synthetic supplements for reducing methane emissions from cattle, sheep and goats are being developed, each with its own set of positive and negative characteristics    
  • Most supplements have only been tested in feedlots. Effectively administering them to animals on pasture, where cattle, sheep and goats spend most of their time and where most methane is produced, could prove challenging
  • The methane offset potential varies considerably among studies of the same supplement, highlighting the fact that impacts are difficult to predict     
  • The lifecycle emissions of many supplements are poorly understood, and so a full understanding of their mitigation potential is lacking
  • Scaling-up the production of some of these supplements in the near-term comes with its own set of challenges.

Methane from ruminant (animals with four-chambered stomachs, including cows, sheep and goats) burps is the  single largest human-caused methane source across all sectors, contributing 25%–30% of global methane emissions. Due to urbanisation, a growing human population and an expanding middle class, global demand for milk and meat is expected to increase by 58% and 74% respectively by 2050 compared to 2010. To combat this rise, several measures for curbing methane from burps are being developed.

One of these measures involves feeding ruminants supplements that inhibit methane production in the stomach. Cows eat carbon contained in plants, and this carbon is converted into methane in the stomach by microbes before being burped out. These supplements work either by physically disrupting methane production, or by shifting the composition of the microbial community away from methane-producing microbes.

Though some supplements have shown promise for reducing methane emissions and are already being sold as voluntary carbon credits, questions remain about the scientific credibility, practicality, scalability, safety and efficacy of these products.

Natural supplements

Red seaweed (Asparagopsis) has received a lot of media focus in recent years on the back of trials reporting methane emission reductions of up to 98% (when as little as 0.2% of the diet is supplemented with dried seaweed powder). It is estimated that if just 20% of the beef and dairy market in developed countries incorporated the supplement into feed, up to 15% of global methane emissions from burps could be avoided.

The main active ingredient in the seaweed is a compound called bromoform, which is a methane-production inhibitor and probable human carcinogen – although concerning levels of bromoform have not been detected in the tissue or milk of cows fed red seaweed. These seaweeds are also rich in iodine, excessive amounts of which can cause thyroid dysfunction in humans. Concerns have also been raised about the ozone-depleting properties of bromoform. Levels of the inhibitor vary naturally due to the environment and genetics, which could translate into variation in the efficacy of the product.

Probably the biggest barrier to rolling-out this seaweed supplement in the near term is producing enough of it. Harvesting wild populations alone would be unsustainable, so aquaculture techniques would need to be developed, along with land for growing and drying facilities. Ideally, these facilities would be located near farms to avoid transport and other processing emissions, although growing seaweed does have potential environmental benefits, such as CO2 sequestration, water quality improvement and ocean acidification reduction. The development of these aquaculture facilities could support regional economies by using local labour for seaweed growing and processing. 

More modest methane reductions of up to 30% have been achieved using garlic and citrus extract supplements, marketed under the name Mootral. However, this is only based on a few animal trials. In one trial, statistically significant results were only seen after 12 weeks, although the authors attribute this to the refusal of the animals to eat the feed at the start of the experiment. However, no safety concerns have been raised with the use of this product.  

The methane offsets from Mootral are being sold as voluntary carbon credits, called CowCredits, which are issued by Verra. With no lifecycle assessment available, and only a small handful of animal trials published in peer-reviewed scientific journals, it is difficult to properly evaluate the offset potential or efficacy of this product.

Methane reductions of up to 30% have also been found when adding nitrate-rich foods into the feed, as this modifies the microbial community. Nitrate has obtained better results in dairy cows than in beef cows, with a lifecycle assessment of the potential net greenhouse gas reductions in the US dairy industry estimating a 5% reduction in CO2 equivalents. However, a major barrier to nitrate supplements is toxicity from nitrite – a by-product of nitrate metabolism in the stomach.

Synthetic supplements

One supplement that has received regulatory approval in Brazil, Chile and, soon, the EU, and for which there is substantial scientific evidence from animal trials, is 3-nitrooxypropanol, or 3-NOP. It is marketed under Bovaer (a combination of ‘bovine’ and ‘air’). The methane reduction potential averages 30% and lifecycle assessments report 11.7%–14% decreases in whole-farm dairy net greenhouse gas emission intensity when 3-NOP is used. 3-NOP also shows more promising results in dairy cattle than in beef cattle, with the same dose reducing methane emissions more in dairy cows than in beef cows. 

The safety risks of 3-NOP to animals and humans are low. However, the compound degrades rapidly in the animal stomach so it needs to be supplied constantly, for example by incorporating it into feed, in order to work. This may be impractical for animals raised outside the feedlot (a yard or building where animals are fed in intensive production systems).

Typical lifecycle of beef cows in pastures and feedlots in the US

To understand how applicable these supplements may be in highly-developed, intensive beef-production systems, we can use the US as an example. The US is the largest beef-producing nation in the world (12.3 million tonnes in 2019), and the production system has a high proportion of cattle finished in feedlots – though Australia and South America are catching up. 
In the beef production system in the US, a permanent herd of cattle is kept in order to produce calves (called the calf-cow operation). These cattle typically graze on inexpensive pastures such as grass. Of the calves born to this herd, about 60% will be raised on pasture for anywhere between 10 and 23 months (called the stocker operation) after which they will be finished in the feedlot (called the feedlot operation) for a further 100 to 300 days. The other 40% of calves go directly into feedlots for 240 to 280 days before going to slaughter. It is estimated that the permanent herd is responsible for up to 82% of the methane produced in the beef production system.

Methane production across the different operations of the beef production system

The feedlot issue

One obstacle shared by all the above supplements is that they have only been tested in feedlots. While they could, in theory, be given to cows raised on pasture, the practicality of doing so is likely to prove challenging, as feed is not as carefully controlled in pasture systems as it is in feedlots. Moreover, although some may consider cows raised on pasture to be more sustainable because they are eating fibrous plants that humans and other livestock otherwise cannot eat, pasture-raised cows actually burp more methane than cows that are fattened on more easily-digestible and nutrient-dense grains in feedlots. As most of the world’s cows spend the majority of their life on pasture and generally burp more methane than feedlot cows, an effective feed supplement must be effectively applicable to pasture-raised cattle. 

Reducing emissions in pasture-raised animals

For pasture-raised animals, switching to more easily digestible legume forages could help reduce methane emissions. Tannin-rich forages or additives are another natural supplement option that can also be readily used in pasture systems. However, they have more modest reduction potential compared with some of the supplements mentioned above, with results varying greatly depending on the type of tannin. Tannins may negatively impact nutrient and protein digestibility and stomach health, affecting the animal’s ability to convert feed into milk and meat. It has been suggested that 3-NOP (Bovaer) could be supplied in lick-blocks or slow-release stomach devices for cattle on pasture, but the practicality of this has not been assessed. The effectiveness of 3-NOP was also found to decrease when higher amounts of fibre are eaten, implying that even if it were made available to cows on pasture, it may not be effective when low-quality forage is being eaten.     

Environmental considerations 

Though grain-fed feedlot cows produce less methane than grass-fed pasture cows, supplying these grains also comes with its own environmental impact. Feedlots are also significant sources of hydrogen sulphide (a toxic air pollutant) and major polluters of waterways with ammonia, pathogens and antibiotics. Concerns around increased antibiotic resistance are also growing. However, pasture systems come with their own set of concerns. For instance, if cattle production in the US were to shift from feedlot-based to pasture-based, herd size would need to increase by 30% to maintain present-day numbers because cows would take longer to fatten up and there would be less meat per cow. This shift would also result in greater methane emissions and other environmental costs, such as soil erosion, loss of native vegetation and water eutrophication (when water becomes overly enriched with nutrients, depleting oxygen levels). 

Below is a table summarising the attributes of the supplements discussed, including the science (the number of studies and quality of the studies), scalability (how easily could this technology be scaled up for use in the near future), deployability (how readily could the technology be deployed), safety (potential safety concerns to humans, livestock and the environment), reduction potential (the extent to which methane could be reduced) and pasture use (the potential for the supplement to be used in pasture-based systems).    

Summary of the supplements

In summary, many of these supplements are only in pilot phases or need more rigorous scientific research, especially animal trials, to fully understand their potential. There are major discrepancies in the methane reduction potentials reported among studies testing the same supplement, suggesting complex interactions of multiple variables, with impacts that are difficult to predict. Perhaps the biggest limitation of most of these supplements is that they have only been tested in feedlots. Controlling and monitoring the consumption of these supplements by cows in pasture systems, which produce the majority of global methane emissions from cattle, could prove particularly challenging, especially considering the palatability of many of them is low.

Follow Us