The invisible price of soy

I studied Environmental Engineering at Politecnico di Milano, both for my bachelor’s and my master’s degree. I began working on these topics during my master’s thesis, working with Professor Rulli and with the Department of Veterinary Medicine at the University of Milan, with which I still collaborate today. From there I continued with my PhD, starting from deforestation in Brazil linked to soy and then analysing more broadly the link between the livestock sector, the use of natural resources and potential more sustainable and resilient solutions.

What interested me was understanding the link between agricultural production, livestock farming and changes in land use. Deforestation, in fact, is mainly connected to two factors: cattle farming and soy, which is largely used as feed. In this sense, the livestock sector is the real junction of the issue.

Because it is one of the most efficient protein sources currently available for animal feed, and it is very difficult to replace. It is used mainly for poultry, pigs and dairy cattle, that is, in all those supply chains where a high protein share is needed in the diet.

In recent years, in many countries—especially those developing rapidly—demand for animal-based products has increased greatly. And soy, in fact, accompanies this change: it is a plant protein that is produced on a large scale, exported and then turned into feed for animals.

Yes, because China is the current major driver of this demand. A huge share of the soy exported from Brazil ends up there. The question we asked in the research was precisely this: how many resources from Brazil, in terms of land and water, are accompanying this change in diets and lifestyles in China?

The interesting point is that we are not talking only about trade. We are talking about natural resources that are used in one territory to support consumption and production systems elsewhere.

The central point is the animals’ diet. Producing meat, milk or other animal-based products requires large quantities of feed, and therefore large quantities of agricultural resources, starting with the production of cereals and soy itself. That is where an important part of the environmental impact is concentrated: in the use of land, water and crops needed to support livestock farming.

In this sense, the problem is not “the animal” in the abstract, but the entire production system behind its feeding. And this is why soy is so central: because it directly connects the growth of animal production to pressure on territories and natural resources.

Because it is often underestimated. When talking about soy, people often say that it is “better” to import it from Brazil because there, thanks to the favourable climate, it is irrigated very little compared with other countries. This is true, but only if we look at so-called blue water, that is, the water withdrawn for irrigation.

In reality, soy in Brazil still uses a great deal of water: green water, that is, rainwater. And this water plays a fundamental role in the hydrological cycle, soil fertility, ecological balances and the functioning of forests themselves. It is not a free or irrelevant resource just because it falls from the sky.

It means that when a country exports a crop or a food product, whether processed or not, it somehow also exports the resources that were needed to produce it. If I grow soy in Brazil and then consume it in China or in Europe, those resources (land, water, energy) physically remain in Brazil, but the benefit of their use shifts elsewhere.

In the case of Brazilian soy, therefore, all that green water used to grow the crop is in effect “incorporated” into international trade. This is what we call virtual water: an invisible resource, but a very concrete one in its effects.

Absolutely. On the one hand there is Brazil, which uses enormous resources to produce a crop destined for export; on the other there is China, which imports this soy to support its own livestock system. In between there are infrastructures, global trade, power relations and political choices.

And there is also a very strong contradiction: Brazil is an agricultural power, but it continues to have problems of local food security, especially as regards fruit and vegetables. In other words, in many cases it is more convenient to grow soy for export than to produce food for local use.

Partly yes: especially at the beginning it had a positive effect in reducing direct deforestation linked to soy in the areas of the Amazon covered by the moratorium. But the problem has not disappeared; it has shifted.

What happened, to simplify, is that soy continued to expand by occupying land that had previously been pasture, while livestock farming was pushed farther away, including toward Amazonian areas. Thus, the direct link between soy and deforestation became less visible, but the indirect link remained very strong.

Exactly. It is not a matter of saying that today deforestation depends “only” on livestock farming and no longer on soy. The point is that the relationship between the two has become more indirect: soy continues to expand, but it often does so by occupying areas already used previously for other activities, which in turn move elsewhere. For this reason, its responsibility does not disappear: it becomes more difficult to see within a broader territorial dynamic.

The most straightforward solution would be to reduce global meat consumption, and that would certainly help a great deal. But we have to deal with reality: imagining a rapid and large-scale decrease, especially in countries that are growing economically, is very difficult.

For this reason, one important path is to act on animal diets, that is, to find alternatives to soy. Replacing cereals is relatively easier, because there are more options and also many reusable by-products. On the protein side, however, the challenge is more complex.

Yes. Insects have very interesting potential as an alternative protein source to soy. They can have a very good nutritional and protein profile and, above all, their efficiency stems from the fact that they could be reared on organic waste and by-products.

The problem, at least in Europe, is above all regulatory and cultural. Today insects are regulated in a very restrictive way, almost as if they were cattle or pigs, and this greatly reduces their advantage. If you have to use “noble” feed to rear insects, you lose much of the system’s efficiency.

No, there hardly ever is. Even putting everything on 100% insects would create other problems. The most sensible direction is that of balance: producing soy within limits compatible with available resources and without new deforestation, and integrating the rest with other protein sources, from insects to alternative meals.

But none of this really works without public policies: rules, incentives and initial support for the transition are needed. Technical solutions alone are not enough.

That food is never just food. Behind a steak, a glass of milk or a feedstuff there are very long chains of resources, territories and decisions. And that often the greatest environmental impact is the one we do not immediately see: not only the forest that retreats, but also the invisible water that travels with goods and changes the balances of entire countries.

The soy that leaves Brazil to feed the world’s livestock forces us to look at the food system for what it really is: global, interdependent and profoundly political.