A time-series study looking at Brazil’s shift to higher levels of ultra-processed foods in the last 30 years shows these foods significantly contribute to greenhouse gas (GHG) emissions, deforestation and a debilitating ecological footprint.

The study defines ultra-processed foods as ready meals, margarine, sweets, soft drinks, foods containing artificial additives and reconstituted meat products such as sausage.

Experts warn that growing economies such as Brazil will follow the same nutrition pattern as Britain did in the last 100 years, which do not align with climate change targets needed at present.

Dr. Christian Reynolds, co-author of the study and senior lecturer at the Centre for Food Policy, City, University of London, says: “Our findings suggest that diet-related diseases and climate change share an underlying driver and, therefore, should be addressed simultaneously. Multi-component actions and policies targeting multiple areas should be considered.” 

For example, these could include fiscal interventions such as taxes or subsidies, regulation on advertising and improving food and menu labeling with the addition of environmental impacts.

NOVA system assessed food items
The adverse effects of high consumption of ultra-processed foods have been linked to obesity, coronary heart disease, diabetes and cancer but very little has been measured on its impact on the planet.

Nutritionist Jacqueline Tereza da Silva of the Department of Preventative Medicine, University of São Paulo and first author of the study explains that the relationship between food systems and climate change is complex and challenges food security itself.The environmental impact of foods were analyzed per 1,000 calories consumers.

“Food systems are responsible for a third of global greenhouse gas emissions, and yet, at the same time, they suffer from the climate impacts that they help to cause.”

The environmental impact of foods were analyzed per 1,000 calories consumers.

The study, published in The Lancet Planetary Health, analyzed household budget survey data taken from urban Brazilian households between 1987 to 2018.The environmental impact of foods were analyzed per 1,000 calories consumers.

The environmental impact of food items was analyzed, per 1,000 calories consumed, for four food groups outlined by the widely used NOVA system. These are unprocessed/minimally processed foods (G1); processed culinary ingredients (G2); processed foods (G3); and ultra-processed foods (G4).

Diet-related footprints tallied
The study found that while the proportion of G1 and G2 foods in the households diet decreased, G3 and G4 foods consumed increased.

Additionally, the increasing environmental impact of G4 foods was driven by an increase in consumption of ultra-processed meat which doubled its contribution to daily environmental impacts per individual.

Per 1,000 calories consumed, changes in the diet were associated with a 21% increase in GHG, 22% increase in the water footprint and 17% increase in ecological footprint.

Dr. Ximena Schmidt, co-author and Global Challenges Research Fellow at the Centre for Sustainable Energy Use, Brunel University London, laments: "This study shows for the first time how increasing the consumption of ultra-processed foods has produced more greenhouse gas emissions and used more water and land, even in developing countries like Brazil.” 

"We need to help people change their diets to protect the environment and live healthy lives. We need to finally acknowledge that impacts to the environment and health have to be tackled together," Schmidt urges.

Another study conducted by scientists from the University of South Australia (UniSA) previously observed a similar pattern when reviewing studies over 20 years. The study observed that discretionary foods such as confectionery, soft drinks, alcohol and processed food accounts for a vast ecological footprint.