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Premium dog food has bigger carbon footprint than owners’ meals

Dogs fed on premium, meat-rich pet food can have bigger dietary carbon footprints than their owners – but using by-products is a “highly relevant” solution for brands.

In particular, wet, raw, and meat-rich products are associated with “substantially higher greenhouse gas emissions than dry dog food”, wrote the researchers from Edinburgh and Exeter Universities in their study, published in the Journal of Cleaner Production.

They also calculated that the production of ingredients used in UK dog food is estimated to contribute around 1% of the country’s total greenhouse gas emissions.

Producing enough food of the types fed in the UK for all dogs worldwide could generate greenhouse gas emissions equivalent to over half of those from burning jet fuel in commercial flights each year, the experts estimated.

Striking differences in carbon footprints

The scientists used ingredient and nutrient labelling information to calculate the carbon footprint of almost 1,000 commercially available dog foods, based on emissions generated during the production of ingredients.

Their sample included a selection of dry, wet, and raw foods, including plant-based and grain-free options.

The analysis revealed “striking differences” in the environmental impact of commercial dog foods, with the highest impact foods responsible for up to 65 times more emissions than the lowest rating options.

Using large amounts of prime meat – which could otherwise be eaten by humans – pushes up emissions, whilst the use of nutritious carcass parts that are in low demand helps limit environmental impact.

“The results show emissions intensity varied over 65-fold across products, with prime meat driving higher impacts,” the experts wrote. “Ingredient production for UK commercial dog foods contributes 2.3-3.7% of UK food system GHG [greenhouse gas] emissions, or 0.9-1.3% of total UK emissions.”

Dry food, not marketed as grain-free, tended to have a lower environmental impact than wet, raw, or grain-free options. An increase in the use of plant-based dog foods is also likely to reduce emissions.

However, the research team noted that only a small number of plant-based foods were available to test for this study.

They cautioned against making general recommendations such as, “dry food has lower environmental impact than wet”, given the nuance in some of the results. For example, the lowest emission wet, grain-free foods are less emission-intensive than the median main-market, dry food.

“Dog owners often have strongly held views on food format choice and we show much lower impact foods may be available without changing type,” the team wrote.

They acknowledged the challenges in encouraging change in patterns of dog feeding are “substantial”, however the potential benefits of change are “considerable”.

Dog owners who want to reduce environmental impacts but not change food type should check the label description of meat cuts used in the food, aiming for a lower content of prime meat, for example.

The use of low-value by-products is a ‘highly relevant’ solution

The findings “highlight the need for greater transparency and better labelling of dog food ingredients to help consumers make informed choices, as pet ownership continues to rise”, the team said.

They called on the pet food industry to “make sure meat cuts used are of the types not typically eaten by humans, and that labelling is clear”.

This chimes with observations made in 2023 by academics at the University of Edinburgh, who wrote: “The use of by-products is highly relevant for pet foods, where using the by-products that lack other alternative uses, and therefore have the lowest values, would be preferred.”

They added: “Novel ingredients, such as insects, could also play a role. However, the question then becomes how and on what were the insects themselves fed. A circular economy view that considers the system and alternatives is therefore needed to understand the impacts of such approaches. Here again, if very low-value waste or by-product streams could be used to grow insects, then low-impact food could be produced.”

Pet ownership continues to grow, especially in countries like China, where the number of pets has “exploded”, according to a report by NBC in February.