The Climate Footprint of Diabetic and Gluten-Free Diets in Australia

Climate change is a global priority requiring immediate action. A thorough understanding of the source of greenhouse gas emissions is essential to inform reduction strategies. This study aimed to quantify the climate footprint of two therapeutic diets—one diet for an adult with coeliac disease and one diet for an adult with type 2 diabetes—and then compare the climate footprint of these diets with the standard Australian diet and the Australian adapted EAT Lancet Planetary Health Diet. In addition, potential areas for reductions in greenhouse gas emissions were explored. All diets were developed for a 71-year-old male reference person. The amount of carbon dioxide produced by each diet was determined using the GWP* calculator for the reference person. Both the gluten-free and diabetic diet had a measurable climate footprint and were not considered climate-neutral. The diabetic diet produced 1.35 kg of carbon dioxide equivalents [CO2e] per day, and the gluten-free diet produced 2.51 kg of CO2e per day. Meat, dairy, and discretionary foods were the major contributors to the climate footprint of the two therapeutic diets. Substituting lamb for beef and soy milk for cow milk in the Australian context resulted in a 25% reduction in the climate footprint for the diabetic diet and 29% reduction for the gluten-free diet. Dietetic advice to reduce the climate footprint of therapeutic diets for coeliac disease and type 2 diabetes should focus on adapting diets to reduce animal-based products.