The meat industry is known for its significant carbon footprint, and in France, more than half of the population has reduced their meat consumption in recent years. However, people are now also questioning the environmental impact of feeding their pets, which often relies on animal proteins. This issue has gained attention as more individuals become aware of their ecological responsibilities, extending beyond their own diets to include their pets' food choices. Feeding pets accounts for a large portion of their carbon footprint. According to Ademe, the French environmental agency, a cat's annual carbon footprint is around 50 kg of CO2 equivalent (kgCO2e), while for a dog, it ranges from 125 to 595 kgCO2e, depending on its size. This is significantly higher than the average carbon footprint of a French person's diet, which is about 2.1 tonnes of CO2e per year. Cooking meals for pets using human-grade ingredients, such as chicken breast or pork spine, might seem like a healthy option, but it is actually one of the most harmful to the environment. A 2023 study published in La Dépêche vétérinaire found that homemade meals based on fresh chicken emit five times more CO2e than standard dry pet food, and up to twenty times more if made with beef. The issue, according to veterinarian Charlotte Devaux, is that these meals use food products intended for human consumption, which have a high carbon footprint. Industrial pet foods, on the other hand, use "animal by-products," which are parts of animals not consumed by humans, such as skin, bones, blood, and fat. These by-products are derived from the existing meat industry, resulting in a lower carbon footprint compared to human-grade ingredients. Among industrial pet foods, dry food is more environmentally friendly than wet food. A 2022 study in the Scientific Reports journal found that wet food can emit up to eight times more CO2e than dry food. This is mainly because wet food contains a higher proportion of animal-based ingredients for its calories. It is better to choose pet food based on small animals like poultry rather than beef, lamb, or pork. Some pet owners are considering vegetarian or vegan diets for their pets to reduce their carbon footprint. While it is technically possible, Charlotte Devaux explains that it is more complex in practice. Cats, being strict carnivores, require specific nutrients that are hard to obtain without animal proteins. Dogs can follow an omnivorous diet but still have unique nutritional needs. When it comes to commercial pet food, Charlotte Devaux differentiates between veterinary brands and mass-market brands. Veterinary brands offer high-quality vegetarian options, often based on soy, and include necessary nutrients. However, these are not vegan as they contain fish oil. These foods are more calorific than standard dry food and may not be suitable for all pets. In contrast, plant-based lines from mass-market brands often lack essential nutrients. A 2015 American study found that only five of 21 vegetarian pet food products met the nutritional needs of dogs or cats. Insect-based pet food is another option, as insects are rich in protein and nutrients. However, insect farming is energy-intensive and requires continuous heating. Insect feed is also not based on waste, but rather on cereal derivatives used in other types of farming. A 2021 study in the Journal of Insects as Food and Feed noted that while insect proteins are promising for human nutrition, they offer little benefit for domestic animals. Charlotte Devaux confirms that in terms of environmental impact, chicken-based dry food is a better choice than insect-based dry food.