Are soybeans evil? A case for why soy should be replaced as animal feed


This blog will explore the impact of the soy boom - a large explosion in demand for soybeans due to their use as cheap protein-dense animal feed. It will explore the environmental cost of soy production on forests; look at the effect on water and soil quality; and investigate the impact on the human population. Finally, we will explore the options that are being considered to reduce the harm being caused.

Called the ‘‘king of beans’’ by many, soybean is a crop grown for its high protein, vitamin and mineral content, versatility and ability to grow in many climates. Soy is popular in Asian cuisine, and as a meat replacement for vegetarians, though it’s mainly used for animal feed. Soy is grown worldwide, but 80% is grown in only three countries: Brazil, Argentina and the United States. These countries fuel the meat industry - 75% of soybeans are crushed into powder to feed an ever-expanding population of animals, mostly chickens and pigs, enabling world meat production to triple in half a century. Soy production has doubled since 2000, in line with the demand for meat from growing economies like China and India. Brazil is projected to increase production by 30% to 180 million tonnes by 2030 which raises many environmental concerns due to the harmful effects of the current soy boom. So, what are the effects of the soy boom and is it sustainable? 


1. Deforestation and the change in land use

To accommodate the increasing demand, farms have enlarged all across the Americas. Between 2008 and 2016, U.S. farmland increased by an average of 400,000 hectares per year. In South America, soybean farms doubled in size from 2000-2019, totalling 55 million hectares, an area larger than France. Worryingly, rapid expansion is occurring in the Amazon Rainforest, where 4.6 million hectares, an area the size of Denmark, have been converted to farmland.

The conversion of the Amazon into farmland has been slow in the past due to the Amazon Soy Moratorium, an agreement between companies to stop buying deforestation linked soy. Sadly, this success has been eroded by the Brazilian government which has allowed the rainforest to be cut down for farmland and grazing pastures. Loggers use a ‘slash-and-burn’ method, where a deforested area is burned to add fertile ash to the soil, but this has meant an uptick in wildfires during the driest season. This has been devastating for the Amazon which historically was the world’s largest carbon sink of CO2 — it now emits more greenhouse gases than it absorbsA tenth of all known species of plants and animals live in the Amazon; research has found at least 14,000 species have been affected in some way by wildfires, and 10,000 are at risk of extinction due to deforestation. Land expansion also has the potential to displace thousands of indigenous people from their formerly protected land, as the regulation of native reserves was transferred to the agricultural ministry, creating a conflict of interest.

Not just the amazon...

Encroachment hasn’t just occurred in the Amazon, though. All of the biomes of Brazil, illustrated in the map below, have been affected. Additionally, in Argentina, soy production has been the primary driver of the deforestation of 7.8 million hectares of their Gran Chaco forest, incentivised by low taxes. This has displaced the indigenous populace, forcing them to abandon their livelihoods. Soy has also caused deforestation in Bolivian and Paraguayan Chaco regions and is replacing natural grasslands in Uruguay and the central U.S. prairies.

Soy farms make up 8.5 million hectares, or 6%, of the Atlantic Forest, a biome that has been deforested so much it now represents only 15% of its pre-colonisation sizeIn the Pampas, where soy is replacing a long tradition of cattle ranching, correlations have shown that, on average, planting 100 hectares of soy reduces the cattle population by 76. Over 1.5 million hectares, or 10%, has been converted for soy.

The true victim of Soy farming has been the Cerrado, a savanna that covers 20% of Brazil and is home to 10,000 species of plants. The soils are unfertile, so agriculture was limited until subsidies were introduced in the 70s to develop the region. Like the Amazon, the Cerrado is a large carbon sink. Since 1985, it has lost 26.5 million hectares due to deforestation and is releasing emissions at a large rate. The Brazilian Government estimated that the emissions released converting the Cerrado to farmland were equivalent to half of the UK’s emissions in 2009.



2. Water pollution

The Pantanal is the world’s largest tropical wetland. It has yet to be extensively converted to farmland, however the effects of the soy boom have manifested in the water quality, which has been negatively affected by the upstream soy operations. 500 million litres of pesticide have been used on soy in Brazil - 60% of the total pesticide used - averaging 17 litres per hectare. A study showed that at least 10 pesticides and herbicides were present in the waters and sediments of the Pantanal, and the amount of pesticide used in the surrounding highlands was projected by scientists to increase by 4.3 million litres, causing a 46% increase in the wetlands downstream.

A research team analysed river sediments in soy producing regions of Argentina, Brazil and Paraguay and found multiple insecticides in each sample, with some occurring at toxic concentrations for fish. Brazilian streams were found to contain the banned pesticide OrganochlorinePapers have shown that the use of pesticide in areas of intensive farming in the Mato Grosso region around the Pantanal have led to high incidences of childhood cancers, and a  higher rate of birth defects


3. Water Consumption

With every crop extracting from the same soil layers and removing water-storing organic matter, monoculture farming also leads to large-scale water depletion and farmers must provide more water for each harvest. Deforestation caused a yearly reduction in rainfall by 8.4% in the Cerrado from 1977-2010 due to plants no longer supplying water by transpiration which led to an increase in regional droughts. Corporate soy farms have enough resources to continue water use during drought, which leaves smaller farmers and villages with nothing. This has led to events like the ‘Correntina water war’ where 1000 villagers invaded a large farm to destroy water pumping equipment.



4. Soil erosion

Monoculture farming, where the same crop is grown every year, is the most modern method of food production but leads to nutrient depletion and soil erosion. One type of plant growing in a field means that the underground root system is in one layer of soil, depriving it of organics and water. This is remedied by adding fertiliser, to artificially increase soil fertility, but the soil will continue to degrade through repeated harvests. A study done in the 2000s found soy farming in the Cerrado caused the erosion of 8 tonnes of soil per hectare per yearLess diversity in the soil means pests and weeds can affect the farm more. This leads farmers to use more fertilisers and pesticide and weed killers each year, which leads to increasing pollution of the soil, air and water systems.


5. Social issues 

Encouraged by the Bolsonaro government, Brazilian soy farms are being built on occupied land. Over 239,000 hectares of indigenous territory have been greenlit to be built on. An exposé found large soy traders Cargill and Bunge had ties to a farm built on the land of a tribe who were forcefully evicted and even had a member murdered by the farm owners.

Another consequence of the soy boom has been the displacement of family owned farms. The high demand of soybean led companies to take advantage of low taxes and subsidies and buy up land to create massively profitable plantations. The consolidation of land has meant that in countries like Argentina, 50% of soy plantations are owned by a tiny 2% of companies. The number of independent Argentinian farms fell by almost half between 1988 and 2008 as small-holding farmers were outcompeted and bought out or evicted from their property. This pattern has been seen everywhere, with hundreds of thousands of farmers and indigenous people displaced from their land across the Americas - sometimes violently

What can we do?

Greenpeace, who championed the Amazon soy moratorium, have been pressuring to expand the agreement to include the Gran Chaco and the Cerrado and recently staged a protest blocking a soy freighter to demand an EU law to protect the Cerrado. Some companies have signed a manifesto in support of the Cerrado, though Cargill and other large commodity traders have rejected this. British companies have signed a commitment to work to ensure all shipments of soy are deforestation free by 2025. In China, the largest market for soy, the Ministry of Agriculture has promoted reducing soy use and minimising reliance on imports. Large pig farmers, fish farmers and feedstock producers have been reducing soy content in their feeds. Officials reported that if effective policy was implemented, soy demand could be reduced by 30 million tons. Pig farmers have also looked to synthetic amino acids to replace soy content in feed. European and Chinese farmers have also been growing more soy for domestic markets. European soy production in 2021 was nearly 10 million tonnes, an increase of 6%. Research has found that European self-sufficiency is possible if 12% of farmland is planted with soyThe largest soy growing province in China, increased planted area by 700,000 hectares, after encouraging farmers to move away from corn with subsidies. The 14th Five year plan outlines goals to increase Chinese soy production by 40% by 2025 to 23 million tonnes.


Can soy be replaced?

Developments in replacing soy feed, such as alternative oilseeds, processed animal proteins, synthetic amino acids, microalgae feed, and finally, insect proteins are being considered and implemented. Insect animal feed is a form of sustainable circular economy: food waste, animal waste and farming by-products are used to grow insects that produce high-quality protein to feed to animals. The insect protein sector has grown large and has already made waves in the industry. UK retailer Morrisons has started replacing soy in chicken feed with insects to produce sustainable carbon-neutral eggs.


Soybeans are a high protein plant used to make cheap animal food, making it highly desirable to livestock farmers. This has led to a boom for countries that produce it. The soy boom has led to disastrous effects, mostly in South America where rampant deforestation has led to widespread wildfires and droughts, releasing tons of greenhouse gases and threatening native wildlife. This deforestation may have destroyed the Amazon without activists pressuring commodity traders to act, though the Cerrado became the next target. Intensive soy farming uses so much pesticide that toxic chemical cocktails have been detected in water systems in habitats where there aren’t any farms. Rapid expansion of farms, enabled by Brazilian government policy has led to indigenous people being evicted from their land, sometimes violently.  The alternative? Replace soy with the most effective protein source that can convert waste streams to high-quality nutrition – insects.