Does Soy Consumption Harm the Planet? Depends Who’s Eating It

Since Australia’s disastrous fire season and COVID-19 began commanding headlines, the recent wildfires in the Amazon seem all but forgotten. But it wasn’t long ago that social media was abuzz about them and debating who was to blame. On Twitter, a non-vegan asked, “Whose [sic] gonna tell [vegans] that the Amazon is burning for both beef AND soy crops???” A would-be vegan lamented, “Been trying to be vegetarian/vegan in last 2 years and give up after [I] read about the Amazon fires caused by deforestation for soy. I feel tricked.” Even a vegan asserted, “The Amazon is burning to make room for soy as well as cattle, vegans do not get to be smug about this if it’s all we’re doing.”

This idea that vegan soy foods harm the planet and drive rainforest deforestation—or at least shoulder the blame with beef—has existed for years. While the vast majority of the Amazon cleared for agriculture is for cattle ranching, much is also for soy farming. A common misinterpretation of this latter fact has helped to spur widespread demonization of vegan soy foods already long subject to scaremongerers positing that it’s harmful to human health—but the true reason for excessive soybean cultivation is meat, dairy, and egg production. The vast majority of soy grown today is fed to farmed animals, an inherently inefficient process that removes most of soy’s calories and protein from the human food supply and therefore requires far more soy to be grown than would otherwise be needed (yes, even given a hypothetical widespread shift to veganism). As experts now warn that the world’s largest rainforest “teeters on the edge of functional destruction,” clarity is long overdue: the footprint of soy used in animal agriculture massively exceeds that of vegan soy foods. Furthermore, using soy for the latter purpose respects our planet’s ecological limits and should be celebrated, not shunned.

Soybeans have multiple uses and corresponding impacts, some more obvious than others. Understanding the true relationship between soybean farming and deforestation requires examining soy’s highly divergent paths to our plates, in which it is either consumed by livestock first or turned directly into food products. Because the popular narrative usually fails to properly scrutinize these two very different uses—and because vegans are an easy target—the soy foods with the smallest soy footprint have become the scapegoat for those with the largest. Soy-fed livestock foods and livestock-free soy foods have wildly different environmental footprints. Soybeans are actually incredibly land-efficient. This is important because half of all habitable land has been converted into farmland (dominated by animal production) over the past few centuries; eating foods that require less farmland would dramatically decrease humanity’s impact on the natural world. The United Nations Food and Agriculture Organization calls beans and other legumes “climate smart” and “key to global food security,” meaning that they are not only highly nutritious but also nitrogen-fixing, carbon-sequestering, adaptive, and drought-resilient. This, in combination with their water efficiency, means, per Oxfam, that beans and legumes are also not overly demanding of global water resources. Soybeans in particular produce at least twice as much protein per acre than any other major vegetable or grain crop on Earth. But there’s a caveat: the inherent sustainability of soy is contingent upon it being directly consumed by humans, not farmed animals.

As farmers growing this powerhouse bean continue to ravage the rainforest in an insatiable quest for land, the staggering inefficiency of soy’s dominant use becomes clear. Animal farming uses, conservatively, 80 percent of the world’s soy crop, including soy grown in the Amazon—most of this soy feeds “poultry” and “swine”, and some even feeds farmed fish. Fuel and industrial products use the second-largest amount of soy; soy foods come in last at just 6 percent. The disproportionate allocation to livestock is due to the inefficient nature of accessing the energy in soybeans by cycling them through animals first. Most of soy’s protein and calories are converted into things like fur, bones, and bodily waste, as opposed to edible products like meat, milk, and eggs. Research shows, specific to cattle, that “the average efficiency of livestock converting plant feed to meat is less than three percent.” While such figures vary per farmed animal, all animals consume far more food (like soy) than they produce. There’s no getting around this massive opportunity loss of secondary consumption: eating the plant-eater is much less efficient than eating the plant. Even a bean as remarkable as soy is bound by the laws of energy transfer in food chains.

No such energy transfer or loss occurs with the primary consumption of plants. Globally, humans obtain the vast majority of their calories and protein by eating plant-based foods, despite livestock production using almost four times more farmland. Soybeans produce five to fifteen times more protein per acre than meat and milk. If humans’ protein needs were met strictly by soy foods, instead of animals, deforestation would decline by 94 percent. Preserving important ecosystems like the Amazon rainforest would become much easier. Swapping beef for beans like soy would slash greenhouse gas emissions and land use significantly, and a full vegan shift would decrease both even further. The remarkable efficiency of the soybean is precisely why soy protein is appropriated by the livestock industry to feed hungry animals—making the branding of soy foods as “unsustainable” especially ironic.

The association bias linking soy farming mainly to vegan soy foods instead of foods made from soy-fed animals is hard to shake—especially when the truth is so counterintuitive. The Union of Concerned Scientists states that “a typical soybean is more likely to end up in a ham-and-cheese sandwich or a chicken nugget”—indirectly, via the farmed animals eating soybeans—”than a block of tofu.” World Wildlife Fund Europe researchers calculated in 2015 that 93 percent of the average European’s annual soy consumption is “hidden” in the making of the animal-based foods that they consume; more recently, the same researchers found that chicken is the biggest driver of soy consumption in the U.K. The scenario is similar throughout Western countries, where the bulk of the world’s meat and dairy consumption—and therefore hidden soy consumption—occurs. Animal foods ironically are not even considered soy foods, despite requiring massive amounts of soy. Think of this as “ghost soy:” invisible, but as intrinsic to these foods’ production as the animals to whom the soy is fed.

Even when the media and vegan-adverse members of the public acknowledge the soy-livestock connection, the prevailing discourse looks for loopholes to circumvent the need to shift to plant-based diets. Can we blame excessive soy farming on humans’ demand for soy oil, found in many processed foods? No. Soy producers generate large amounts of soy oil as a byproduct of processing soy meal to meet the demand for animal feed—not the other way around. The resulting soy oil is then marketed and sold for human use. Can we source poultry and pork from farms that do not use soy-based feed? No, again. Even locally raised “heritage” breeds of farmed birds and pigs are predominantly fed soy—much of it Amazon-grown—as are many of their bovine counterparts. Why not just feed these animals a different plant protein? The root of the problem is not soy or the plant protein source itself, but rather humans’ inefficient secondary consumption of plant protein through livestock animals. Could we let the farmed animals eat grass instead of feed? No, because grass is less nutrient-dense than soy and other plant proteins; meeting the demand for all animal protein solely through pastured “grass-fed” ruminants (mostly cattle, sheep, and goats) would slow the animals’ growth rates and therefore require even more farmed animals, and more land. Should we simply “#BanBrazilianBeef” to protect the Amazon? The soy feed production problem would persist even if ranching ceased in Brazil, as would the already-huge grazing burden elsewhere. For example, the vast majority of deforestation in Australia has also been for grazing livestock; animal farming practices have replaced indigenous land management practices, resulting in soil degradation and undergrowth build-up linked to that country’s own recent wildfires.

As the world’s largest user of land, animal farming has long been displacing native forests everywhere. Yet, due to shifting baseline syndrome—in which people fail to perceive the ongoing transformation of the natural world occurring over generations—humans’ conception of how much of the planet has been converted to animal farming is lacking. Land use in both the U.S. and U.K. is dominated by livestock grazing, and often the land has been historically deforested for that purpose; a double standard is occurring when meat-eaters in these countries criticize Amazon-produced beef. Cattle ranching, regardless of where it occurs, uses immense amounts of land—cattle farms occupy more than half of the world’s total agricultural land while providing less than two percent of humans’ calories and five percent of protein worldwide.

Soy foods for human consumption occupy a comparably light footprint, yet consumers of these foods still desire to avoid compounding upon the problems largely created by “ghost soy” production. Vegan soy foods can become even more eco-friendly when thoughtfully sourced to support local farmers and eco-conscious businesses. The conservation nonprofit organization Rainforest Rescue assures Europeans that “soy for human consumption is mostly grown in Europe and does not drive deforestation.” Most U.S.-produced soy foods—including the Impossible Burger—appear to overwhelmingly use North American-grown soybeans; various brands’ soybean sources and other sustainability criteria can be confirmed via this organic soy food scorecard. Regional brands—such as the Northeast’s The Bridge tofu, which is made in Connecticut from organic soybeans grown in upstate New York—are often the most eco-friendly. The subversive spirit of many such companies is exemplified by the Pacific Northwest’s Saruta SoyFoods, whose website describes the company’s offerings as “a protein source that comes straight from the earth’s bounty, without first routing that bounty through the belly of a beast.” Whether purchasing traditional fare like tofu that is considered an ancient art form or modern innovations like the soy-based meats disrupting the food industry, consumers can support food producers whose values align with their own.

From a health standpoint, the undesirable agricultural practices associated with soybeans grown for animal feed should not be conflated with those separately graded for organic soy foods. The latter is prohibited by the U.S. Department of Agriculture from being genetically modified or grown with synthetic pesticides. The world’s largest organization of nutrition professionals, the Academy of Nutrition and Dietetics, supports soy as a healthy food staple. Cleveland Clinic explains that soy is a cholesterol-free complete protein, high in fiber and with plenty of healthy polyunsaturated fats, including omega-3s; soy is also rich in vitamins, minerals, and phytochemicals. Much of the anti-soy confusion centers around its phytoestrogens, which are naturally occurring plant compounds that either weakly mimic or actually block estrogen’s effects. Phytoestrogens are not estrogen. Sixty to eighty percent of actual estrogen in human diets comes from animal dairy, a fact that is poorly known and oddly not subject to nearly as much public scrutiny. This confusion has not stopped the spread of conspiracies claiming that soy foods, a significant part of traditional Asian diets, emasculate men and cause diseases. Such anti-soy paranoia, originating from disinformation about foods that threaten the livestock industry’s unrivaled dominance, is likely rooted in a toxic combination of pseudoscience, misogyny, and xenophobia.

Despite the many environmental and health benefits of consuming soy directly, the misconceptions persist. It’s become commonplace for consumers to mistakenly connect traditional global staples like tempeh and soy milk to the environmental degradation of the Amazon, especially in the wake of its recent fires. Media outlets like Vice claim that “vegans and vegetarians aren’t off the hook,” falsely linking Amazon deforestation to tofu production. Last summer, Finland’s Minister of the Environment and Forests urged the public to “replace soy in all uses,” including, absurdly, in “non-animal foods.” Viral headlines recently amplified a veterinarian’s wild claims, published in a livestock publication, that soy burgers cause “man boobs.” Soon after, a highly speculative presentation given at a farmers’ conference, based on unpublished research to be “interpreted with caution,” suggested that tofu—given certain specific and complex production scenarios—“may” be more climate-intensive than some meat. This embrace of such implausible claims, characterized as “news,” from questionable sources, while overwhelming evidence proving otherwise receives little attention, reveals a strong tendency toward confirmation bias. Even many articles intending to “clarify” that soy foods for human consumption are not the culprit still perpetuate the idea that these foods need to be eaten sparingly to protect our health and that of the planet. In truth, embracing soy as a protein staple in place of animal-source foods can be a meaningful part of the solution.

With the Amazon—along with our planet—facing an existential threat, insidious false narratives are encouraging consumers to vilify eco-friendly soy foods. The resulting cognitive bias and false claims regarding soy do not stand up to scrutiny. To help heal the planet, reams of science urge a shift to plant-based diets that center on pulses and legumes, including soy. Soy is a beacon of protein efficiency when consumed directly, but not when processed through animals to produce meat, milk, and eggs. Overlooking this chief reason for soybean overfarming misplaces the blame on, and socially devalues, animal-free soy foods. Animal agriculture is inextricably linked to the disproportionate use of land and resources, and the use of soy-based feed is just one way of many that this dynamic manifests. No tweak to agricultural practices can make animal-based foods more efficient than plant-based foods. The fact that plant-based eating alone will not save the Amazon does not negate its dramatically smaller land use. Adopting a plant-based diet is, therefore, a logical entry point for individuals to reduce the need for additional deforestation. Herein lies the paradox: meaningfully tackling the rainforest’s misunderstood soy problem requires a collective shift from consuming animal proteins to eating only plant proteins—yes, soy foods included. Soy consumption is, of course, optional—but disparaging soy foods is counterproductive to the aim of reducing humanity’s strain on global resources. Let’s shift the narrative and proudly reclaim the magnificent, efficient soybean as delicious and nutritious food, not animal feed.