The International Down and Feather Bureau (IDFB) commissioned an independent Life Cycle Assessment (LCA) by Long Trail Sustainability to compare the environmental impact of down and synthetic fill. Analyzing five key categories—human health, ecosystems, resources, energy demand, and climate change—the study revealed that down has 85 % to 97 % lower impact than polyester across all areas. For climate change alone, down’s impact is 94 % lower. Choosing down not only help with effective climate action but also provides exceptional warmth without added weight. Ethically sourced and fully reusable or compostable, down stands out as the most sustainable and eco-friendly filling material available.