Global food systems are contributing to a shift toward unhealthy diets, which is linked to the three components of the global syndemic. This cross-sectional study evaluates how dietary patterns in Brazil are associated with the components of the global syndemic. Anthropometric and food intake data were obtained from the CUME Study—a prospective cohort conducted with a sample of Brazilian university graduates. BMI was used to assess obesity. Insufficient intake of micronutrients was considered undernutrition. Carbon, water, and ecological footprints were used to assess the environmental impact of dietary patterns. Dietary patterns were identified through principal components analysis. Linear regression models were used to evaluate associations between dietary patterns and the components of the global syndemic. The Unhealthy Dietary Pattern was positively associated with BMI and had the highest environmental impact. The Brazilian Dietary Pattern was also positively associated with BMI but had the lowest environmental impact. The Healthy Dietary Pattern was the most protective against micronutrient inadequacy. Diet affected the environment and people’s health in this sample. The dietary patterns identified here as contributing to poor health and environmental damage can help the government develop policies that incorporate the costs of these effects into the prices of food.