University of São Paulo: Less red meat, more variety: a mixed diet can be the path to sustainability and food security

If the consumption of red meat in Brazil were replaced by a diverse diet, composed of animal and vegetable proteins, 809 million hectares (Mha) could be saved, 1 billion tons of carbon equivalent would no longer be emitted and 720 trillion liters of water could be saved. These are some of the results of Ana Chamma’s master’s degree, carried out at the Luiz de Queiroz School of Agriculture (Esalq) at USP.

Under the guidance of Gerd Sparovek, professor at Esalq and coordinator of Geolab, Ana, who is a sanitary and environmental engineer, developed her work with the objective of presenting a new approach to guarantee food security for the Brazilian population and, at the same time, sustainability. from the country.

Another interesting fact was that the diet of the Midwest region, based on beef, causes the greatest impacts, both on land use and water use. In addition, it emits more greenhouse gases into the environment.

The one based on fish and seafood, consumed in northeastern regions, is the one that causes the least damage.

Food consumption tends to grow in the coming decades, especially those of animal origin, while the available areas will become increasingly scarce. Ana told Jornal da USP that the existing solutions to tackle this problem are usually focused on expanding new areas for production or increasing the yield of arable land, without considering the real demand for food. “When you think about climate change, you usually look at transport, at energy, but food is also a point that deserves our attention.”

“The inversion of logic came from Ana. She understood that, with the inversion, the results would be more easily communicated and understood by non-specialists in the subject. And it worked, it was a great idea”, celebrates Sparovek.

With this in mind, the researcher proposed a new methodology, called “from the table to the field”. Instead of thinking about expanding food supplies, Ana focused on reducing the environmental impact through food demand.

In the first part, the possibility of expanding areas for agricultural production was tested based on a Brazilian urban diet, defined by data contained in the 2008/2009 Family Budget Survey (POF).

Land use, carbon footprint (a measure that calculates the equivalent carbon emission in the atmosphere by a person, activity, event, company, organization or government) and water (an indicator of the volume of fresh water spent in the production of goods and services ) were analyzed in eight scenarios, which consider different types of productivity levels and food loss.

For the scenario that represents the current system, it was estimated that 292 Mha should be used in Brazil only to meet the needs of the population. MapBiomas data show that, currently, agriculture occupies about 30% of the national territory (something around 225 Mha), with 167 Mha composed of pasture areas, 64 Mha of agricultural areas and 24 Mha of areas of undefined use. (a kind of mosaic of pasture and agriculture).

If we consider the growth projection of the number of inhabitants for the year 2050, and if nothing changes, the use required by the urban diet would be 321 Mha.

In situations where measures to reduce food loss and gain productivity were adopted, 53 Mt of carbon equivalent and 43 trillion liters of water could be preserved in Brazil annually.

In another step, the engineer investigated how the different Brazilian diets cause damage to the planet and whether a change in eating habits has any positive effect.

“We believe that simple changes, such as consuming different types of proteins in a week, could minimize this damage”, says Ana. “Integrating measures to intensify agricultural productivity and reduce food loss, combined with the modification of eating habits, is an alternative for mitigating climate change”.

The Food and Agriculture Organization of the United Nations (FAO) predicts that 9 billion people will inhabit the Earth in the year 2050 , that is, we will have at least 1 billion more people on the planet in need of food 30 years from now.

Ensuring enough food for these people – qualitatively and quantitatively – and that it comes from sustainable systems is one of the great challenges of the 21st century. The Sustainable Development Goals (SDGs) – a United Nations call to action to end with poverty, protect the planet and ensure that all people have peace and prosperity – for example, they are made up of 17 goals. One of them is the promotion of Zero Hunger in the world.

Data show that, in Brazil, from 1985 to 2018, areas destined for agriculture increased by 2.5%, and pastures grew by 37%. The areas of native vegetation fell by 13%.

It was thinking about this whole scenario – and also about presenting a sustainable solution for the planet – that Ana designed her study. The first chapter aimed to understand the real need to use resources for food production from the food demand of the population.

The diet adopted by the researcher was urban – as it represents the region where most of the Brazilian population lives – and consisted of five daily meals (breakfast, lunch, afternoon snack, dinner and supper) based on the amounts of food recorded. by POF.

Then, the researcher matched these products to the productivity data. In the next step, she integrated this information with that of environmental variables, available in another research, carried out by Josefa Garzillo at the Faculty of Public Health (FSP) at USP.

Eight scenarios were created, which combined current and future yields and levels of food losses across the agri-food system.

The first one took into account the productivity for the years 2017/2018 without any loss in the system. “It is a fictitious scenario, but it is important to understand the effect of food losses on the generation of the environmental impacts addressed”, explains Ana.

The subsequent ones were simulated using the productivity of the years 2017/2018 and the losses at different levels (domestic environment, agricultural production, harvesting, storage, processing and packaging, retail and distribution).

According to Sparovek, the challenge, from a methodological point of view, was greater than what is normally seen in master’s dissertations. “The combination of the databases we use is not easy to do, it requires a lot of knowledge about the databases and database operations. Ana was able to do this by having dedicated herself to scientific initiation since graduation and having followed other works in our laboratory”, says the advisor.

For this system, it was estimated that 292 Mha should be used in Brazil only to meet the needs of the Brazilian population. Taking into account the population growth projection for the year 2050, the use required by the urban diet would be 321 Mha, if nothing changes.

By reducing losses and gaining productivity, 53 Mt of carbon equivalent could be reduced and 43 trillion liters of water preserved. For the optimized scenarios, if there was an intensification of livestock and/or a reduction in food losses, the expansion of areas would not be necessary to meet future demands (2050).

“The perfect situation would come from an increase in productivity combined with a reduction in losses in the system”, explains the researcher.

Diets by region and campaigns
Along the way, the engineer identified the amount of land needed to generate products of animal and plant origin. For animal production, around 195 Mha would be needed and for vegetable production, 48 Mha. “It is a very big difference”, says Ana. “In this step, we get clues about which diet would be more sustainable.”

The second chapter aimed to identify the magnitude of impacts generated by food consumption, such as land use, greenhouse gas emissions and water resources. In addition, we sought to understand whether changing eating habits could have any relevance in controlling climate change.

For this chapter, the methodology adopted was the same. The database was expanded and 17 diets were elaborated, divided into four large groups: regional, household situation, income class and models. “All the menus contained the same caloric consumption, but with the introduction of a different protein in each one of them”, he explains.

Four scenarios were simulated and the effect of two campaigns that encourage a change in eating habits was analyzed.

Second without meat , carried out in partnership with the Brazilian Vegetarian Society (SBV), seeks to inform and educate the population about the impacts of the use of animal products on society, health, animals and the planet, in addition to encouraging the replacement of meat for vegetables at least once a week.

The Less is More – Reducing Meat and Dairy for a healthier life and planet campaign, launched by Greenpeace, aims to reduce the consumption of all types of meat and meat products worldwide by 50% by 2050.

Less red meat, more sustainability
The analysis of regional diets showed that the menu in the Midwest region of the country causes the greatest impacts, both on land use and on GHG emissions and water use, due to the higher consumption of beef protein in the menu. Consumption requires an area 1.4 times larger than diets in the North, South and Southeast and 2.5 times larger than in the Northeast region, which has the lowest impacts due to fish consumption.

The impacts generated by the food consumption of different groups of income class and household situation, as well as the North, South and Southeast regions, did not show significant variation.

Taking the diet of the Midwest region as a reference, if the best scenario were adopted, 54 m2 per capita daily could be reduced to 29.1, that is, 1.8 times less. As the impacts on water and carbon footprints depend on the level of food loss in the system, in the scenario where loss reduction occurs, 0.3 thousand liters of water could be saved and 0.5 kg of carbon equivalent per day, by each individual, would no longer be issued.

Alternative diets, particularly those that consume small amounts of red meat, could, if widely adopted, reduce GHG emissions from agriculture, reduce land sprawl, and generate much smaller water and carbon footprints.

The high consumption of beef in the diet impacts 18 times more land use than a plant-based one. “I remember that I drew a parallel between the extremes: if the entire population only ate red meat, it would take almost 800 million hectares a year to meet this demand; for a vegan diet, 50 million hectares would be enough”, says Ana.

The researcher also emphasizes that we do not need to be so radical. “We didn’t want to give solutions that were totally unrealistic. If, during the week, we consumed different animal proteins each day, two days of vegetarian menu and one day of vegan menu, this mix would bring a very cool result”, says Ana. “Also, having awareness programs in schools and other institutions, for example, would help improve outcomes.”

Sparovek told the USP Journal that the awareness that diet choices differ greatly in relation to environmental impacts is a much more conversation starter than with more abstract and harsh topics, such as greenhouse gas emissions or biodiversity. “This awareness can help people understand the connections of their choices, not only in relation to diets, but other dimensions of their way of life, with environmental issues.”

“Measures that reduce food loss should also be on the radar of public policy makers. Worldwide, 1.3 billion tons go to waste annually. Many people would not go hungry”, he concludes.

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