So you want to save the planet? Put your dog on a vegan diet

If you’re eating less meat for the planet’s sake, good for you – but what about your dog? Switching all the world’s pooches to a plant food diet would save a lot of greenhouse gases: more than all those emitted by Britain, says Dr Andrew Knight, a professor of animal welfare affiliated with Murdoch University’s school of veterinary medicine.

A vegan diet can be good for your dog, and the planet.Credit: Getty Images

That’s food for thought for us dog lovers, given last month’s State of the Climate Report 2024 from the Bureau of Mereorology and the CSIRO, which told us (as if we didn’t know) it’s time to get a grip on greenhouse gas emissions.

Trimming our own and our pets’ meat intake can help tackle this – the livestock that feeds us and our pets accounts for 25 to 30 per cent of global GHG emissions, Knight says. And if you still think dogs are designed for a meat-only diet, here’s some evolutionary history. When a few bold wolves first crept closer to hunter-gatherers thousands of years ago, they kicked off the process of dog evolution, including changes in digestion as they adapted to eating the plants that were part of a hunter-gatherer diet.

In other words, dogs, unlike their wolf ancestors, are omnivores and can do well on a vegan diet, says Knight, whose latest study was published in September and found that, compared with dogs fed on conventional meat or raw meat diets, dogs eating vegan food were less likely to be overweight or obese, have allergies, skin or gastric problems. It’s one of 11 studies now showing dogs do well on vegan diets – though it’s not as simple as sharing a tofu stir-fry with your pet, he stresses. Good commercial vegan dog food, with protein provided by plants such as legumes, seeds and grains, is a safer bet than the home-cooked version because it’s formulated to provide all the nutrients dogs need.

Signs show the interest in feeding dogs more plant food is growing. Vegan business magazine Vegconomist reported last year that the vegan dog food market was worth $US13 billion globally, and was expected to increase to $US26 billion ($39 billion) globally by 2033. And while the traditional pet food market has grown by 6 per cent since 2016, plant-based pet food has jumped by 31 per cent in the same period – almost six times faster, according to Euromonitor.

So what do vets have to say about feeding dogs legumes instead of lamb? The Australian Veterinary Association is cautious: It doesn’t oppose a vegan diet but suggests that dog owners check with their vet first, while the British Veterinary Association concedes: “It is possible to feed dogs a plant-based diet, but owners should be aware of the difficulties in balancing these diets for nutritional needs, the lack of robust long-term data on their safety, and should monitor their dog’s health for long-term impacts.”

Knight disputes this. “We don’t need longer-term studies. In most studies of vegan diets, dogs were maintained on their diets for at least one year, which equates to around seven human years for an average dog, and in some studies dogs were maintained on their diets for an average of 3½ years, so most of these studies are long term,” he points out. “To reject this and call for longer-term studies, when the evidence is already so strong, is unreasonable. It isn’t asked for with respect to meat-based diets, and reveals a bias against vegan diets.”

But even swapping just some meat meals for a nutritionally balanced, plant-based pet food would help create a more sustainable diet, Knight says.

It’s also a way of doing our bit for animal welfare. The lambs’ ears and pig snouts in the pet shop dog treat aisle are a reminder of what other animals have to go through to provide food for our pets. Brownie points for using the whole animal, of course, but if more dogs and their owners trimmed their meat intake, fewer animals would have to endure factory farming. While some animals are lucky enough to get treats, others are doomed to become treats.

Paula Goodyer is a health writer.