Dog and cat owners could significantly reduce the environmental impact of their pets’ diets by feeding them dry food (consisting of kibble or biscuits) rather than wet food with higher water content. This is according to a study of Brazilian pets that will be published today (November 17) in the journal Scientific Reports. The findings highlight how pet owners can provide their animals with sufficient nutrients and calories while feeding them more sustainably.
Worldwide, the population of pet cats and dogs is growing substantially. Currently, the USA is estimated to have 76.8 million dogs and 58.4 million cats, while Brazil has 52.2 million dogs and China has 53.1 million cats. However, the environmental impact of pet diets is unclear.
Feeding a 22-pound dog a wet diet would cause 6,541 kilograms of CO2 emissions per year, 689% more than a dry diet.
Marcio Brunetto and colleagues evaluated the environmental impacts – including greenhouse gas emissions, land use, and water usage – of 618 diets for dogs and 320 diets for cats in Brazil. The authors investigated commercial wet diets and dry diets found on the websites of three major Brazilian pet food retailers. These were also compared to homemade diets – either food produced by companies, or food cooked by owners at home using recipes provided by companies. Additionally, the authors assessed the nutritional and calorific makeup of the different diets.
For all variables, wet diets for cats and dogs had the greatest environmental impact, particularly compared to dry diets. Homemade diets tended to have intermediary environmental impacts, although water usage in homemade cat diets was similar to dry diets. The authors estimate that a ten-kilogram (22-pound) dog consuming on average 534 calories per day would be responsible for 828.37 kilograms of CO2 per year when fed a dry diet compared to 6,541 kilograms of CO2 per year for a wet diet – an almost seven-fold increase (689%).
Dry diets provided the highest amount of energy per gram, while wet diets and homemade diets provided higher amounts of protein. In wet diets, almost twice as much energy was provided by animal ingredients compared to dry diets (45.42% versus 89.27%), which may contribute to their greater environmental impact.
These results highlight the extensive environmental impacts of pet foods, the need to make them more sustainable, and an indication of how this may be achieved.
Reference: “Environmental impact of diets for dogs and cats” by Vivian Pedrinelli, Fabio A. Teixeira, Mariana R. Queiroz and Marcio A. Brunetto, 17 November 2022, Scientific Reports.
“Some of the GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), ozone (O3), and water vapor.” Why is water vapor put last in the list when it is the most powerful?
“… livestock accounts globally for 77% of farming land and produces only 37% of total protein.” Presumably, that includes the livestock intended for consumption by the 8 billion humans on the planet. Something that is not mentioned is that grazing animals can take themselves to water, and don’t require an environmentally-degrading infrastructure to supply water, as with much agriculture. Additionally, grazing by animals can and does usually take place on marginal lands unsuitable for conventional agriculture.
Dogs (omnivores) are more tolerant of vegetables in their diet than cats (obligate carnivores). However, my dog clearly had issues with her kibble diet that caused her to emit considerable methane on occasion!
I’d like to know if the authors of this study are voluntary vegetarians or have other potential philosophical conflicts of interest.
That’s amazing! It’ll work for children and the elderly too. How do we make people switch their homemade diets to kibble? Marcio Brunetto and colleagues eat kibble, and you should too.
Go for it.
Realize that any giving time countless pets all over the world are suffering because of mistreatment/neglect & it will always continue as long as humanity keeps using animals as pets!
What gives humanity right to enslave any animals for entertainment as toys?
Also consider countless diseases/parasites keep jumping between humans & their pets!
Also consider massive amounts of money/labor/food/medicine keep getting wasted for pets!
Also consider countless people illegally running “farms” to produce pets to sell!
Also consider invasive species problems & harms of international pet (wild animal) trade!
People should/must avoid using ANY animals as pets!!
People who are addicted to pets (because of growing up w/ pets and/or living w/ pets for many years) should/must switch to robopets!!
“What gives humanity right to enslave any animals for entertainment as toys?”
I think that my dog would (If she could) disagree with your assessment of her being a slave. She follows me from room to room in the house, and when off-leash on a hike, never lets me out of sight. There is a joke about why a dog is better than a wife: Because the later you get home, the happier the dog is to see you. I don’t think that you understand the relationship between a pet and their owner.
YES!, they are far better off living in landfills and alleys starving, foraging through garbage, suffering from internal and external parasites…
I’ll continue to feed my dogs our own custom cooked wet “healthy” food versus the cancer causing dry kibbles.
I’m starting to get really fed up with the propaganda pieces disguised as “science” here.
Crap like this, claiming video games cause sudden heart failure and death, contradicting stories, etc….
I came here because this site is supposed to be SCIENCE and I wanted to avoid the crap published everywhere else but its just as bad here!!!!
Might have to ditch this site as well. Either stick to actual SCIENCE or change the site name!
More insnce “save the planet advice”. Stopping my cats eating meat won’t do a thing to prevent the world’s climate from changing, as it always has always will until the sun becomes a supernova and fries us all to a crisp.
However, making them eat dry stuff will – unless my vet is as a big a charlatan as a lot of climate scientists – gradfually ruin their kidneys and end all of their nine lovely lives prematurely.
So kindly get knotted, Mr Brunetto and team.
This article is trash. Dry cat food causes less CO2 emissions because it increases the risk of premature death due to the cat being in a constant state of dehydration. Cats have a very low thirst drive, and they get most of their water from their food. Studies have shown that a cat on an all dry diet won’t drink enough water to make up for the lost moisture. Oh, and most dry cat foods have corn as a main ingredient, which causes obesity and diabetes. So yes, I want cat food that is mostly made from animal sources.
This is animal cruelty. Cats and dogs and cats are carnivores and feeding them a dry diet often leads to liver failure over time.
Feeding a male cat dry food could lead to a urinary blockage and kill him.You should tell people that your supposed to be so smart.Dumbaases.
Who really wrote this non article – Billy Gates. These kind of lies are so disgusting and they’ve been trying pull this wool over everyone’s eye as long as I’ve been alive-64 years. Don’t believe these idiots because they’re full of 💩 and hate humans.
Dry kibble is the leading cause of crystal formation in the urinary tract and other urinary infections in cats. Dry kibble is the leading cause of obesity in cats. Very disappointed that this supposed”science” site did not report this.
Lol. Environmentalism is a huge passion of mine. So are my dogs… Why dont we let our animals continue to eat healthy foods and focus on our unsustainable diets?
Amazingly, it turns out that giving your pets less water consumes less water!
Much like this website is obligated to pander iffy takes on studies via ragebait articles, my cats are obligated to consume water and meat.
A lot of logical fallacies and anger in the comments section.
Science isn’t “fake” just bc it doesn’t reflect people’s preferred findings. Food doesn’t cause cancer just bc it’s not considered “all natural”. Lead is natural, so it should be safe to feed.
This is almost comical. Rich and elite are omiting a million times more carbon emissions than he average person…lol but don’t worry about it cuz making a switch from wet to dry food for your oets will make up for it, they need to continue their lavish lifestyle.
Before u know it we won’t even be allowed to eat regular meat, it’ll all be lab grown meat with bug fillers. The climate is not constant,the only thing constant is CHANGE. Keep pushing this type of propaganda, see where TF it gets us. Smh
I will preface this by saying I am a veterinarian. Even if this is true it’s not worth it for your pet. They need a water-rich diet, please don’t feed them dry food only. It’s very high in carbohydrates and very water depleted.