Trends in greenhouse gas emissions from Brazilian foods using GGDOT Concerns regarding the relationship between climate change and food production have called the attention of scientific, governmental and non-governmental institutions. The accumulation of anthropogenic greenhouse gases (GHG) is well established as the main cause of climate change, with over 20% of these emissions coming from food production. Even if clean energy targets are met, greenhouse gases will rise due to methane and nitrous oxide generated by agriculture. This, coupled with the increasing demand for high protein food, will arguably drive food to top priority on the climate change mitigation agenda. Furthermore, food production is likely to be affected by climate change, compromising food security and jeopardising achievement of the second United Nations Sustainable Development Goal: "End hunger, achieve food security and improved nutrition and promote sustainable agriculture", with major ramifications for the global poor. Brazil is one of the most populated and agriculturally productive countries in the world and as such has an important contribution to greenhouse gas emissions. At the same time, Brazil is one of the first to consider sustainability in its National Dietary Guidelines. The third of five principles underpinning the guidelines focuses on "the interdependence between healthy diets and the social and environmental sustainability of the food system''. The guidelines are meant to advise and empower people to make better food choices. However, due to the lack of metrics to assess the impact of foods on the environment, it was not possible at that time to directly incorporate the information about GHG emissions in the recommendations given by the guidelines. Changing what Brazil eats has a large impact on the environment, population health, and on the Brazilian economy. Brazil is the third biggest agricultural producer worldwide, with a forecast value of US$183 billion by 2021, yet agriculture and land use change account for about 55% of Brazil's GHG emissions. Simultaneously, 57% of the Brazilian male population is overweight or obese, and the number of people with diabetes has more than doubled over the past three decades (15%+ of the population), leading to obesity healthcare costs rising to $330 billion over the next 40 years. Managed sustainable healthy dietary and food systems change is needed if Brazil is to meet its National Policy on Climate Change (38.9% GHG emissions reduction relative to 2020 emissions projections), sustain its agriculture sector and reduce healthcare spending. This project will offer tools and map pathways, which  public policymakers can call on to shift towards healthy sustainable diets, thus promoting the economic development and welfare of Brazil. This proposal brings together experts on food nutrition and GHG in Brazil (Levy and Garzillo) with experts in data science, consumer behaviour and food emissions from the UK (Bridle, Reynolds and Schmidt, respectively), through the work of Silva, who has previously worked in Brazil with Levy and over the past year in Manchester has contributed to GGDOT (Greenhouse Gas and Dietary choices Open source Toolkit). Our collective long-term ambition is to help reduce greenhouse gas emissions from food. As a step towards this, the overall goal of this proposal is to help the Ministry of Health of Brazil to fulfil its goal of making dietary recommendations which are both healthy and sustainable. We will achieve this by quantifying past food trends in Brazil and trying to influence future food trends. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.