EDINBURGH, SCOTLAND — Often overlooked as a contributor to environmental impact, ingredient sourcing for pet food production can have dramatic effects on the environment, especially for diets using “prime meat” (likely defined as high-quality cuts of meat) as opposed to animal byproducts, as demonstrated by recent research in the United Kingdom. With human grade and raw feeding trends on the rise, it can be inferred that the amount of prime meat to be used in pet food production will only increase moving forward.
Published in the Journal of Cleaner Production, the study was conducted by Principal Investigator John Harvey of the Royal (Dick) School of Veterinary Studies at the University of Edinburgh and the Center for Rural Policy Research at the University of Exeter; Sarah Crowley, Ph.D., of the Center for Geography and Environmental Science at the University of Exeter; Vera Eory, Ph.D., of Scotland’s Rural College; and Peter Alexander, Ph.D., of the Royal School of Veterinary Studies and the School of GeoSciences at the University of Edinburgh.
The study analyzed 996 dog foods of different formats sold by a single retailer in the United Kingdom — 526 dry, 114 dry grain-free, seven dry plant-based, 197 wet, 113 wet grain-free, five wet plant-based and 34 raw. These diets were then assessed by an open-source tool developed by the researchers, enabling granular comparison. Impacts are calculated per 1,000 kcal of metabolizable energy and converted to per mass of food produced for comparison with other studies.
Source: Harvey et al., 2025The results show emissions intensity varied more than 65-fold across products, with prime meat driving higher impacts. Due to this, wet and raw diets were found to have higher environmental impacts than dry diets. Additionally, grain-free diets were found to have higher environmental impacts, while plant-based diets were found to have significantly less impact.
“Our findings demonstrate that shifts toward increased feeding of wet food, in countries where currently a small proportion of the market, could have dramatic effects on environmental impacts,” the researchers wrote.
Ingredient production for UK commercial dog food contributes 2.3% to 3.7% of UK food system greenhouse gas (GHG) emissions, or 0.9% to 1.3% of total UK emissions, according to the study. Extrapolating from UK results, to meet global dog population feed needs for commercial food the researchers estimate emissions of 469 to 792 metric tons of CO2 equivalent for ingredient production.
Based on annual sales volumes, UK commercial dog food ingredient production results in GHG emissions of 4.7 (economic allocation), 6.6 (mass allocation), and 11.6 (no allocation) metric tons of CO2 equivalent; land use of 1 (economic allocation), 1.3 (mass allocation), and 2.7 (no allocation) megahectares; and freshwater use of 0.75 (economic allocation), 0.87 (mass allocation), and 1.15 (no allocation) cubic kilometers, according to the study. These emissions represent 2.3% to 3.7% of UK food system emissions.
“More attention needs to be paid to the environmental impacts of feeding pets, including improved understanding of the ingredients supply chain and how moves to less impactful diets can be supported,” the researchers wrote.
Read more about sustainability efforts across the pet food and treat industry.
