A new peer-review study has concluded that nutritionally complete vegan diets for dogs may be linked with better health and could be less hazardous than meat-based diets. To help clarify the potential health effects of different dog diets, an international team of researchers analysed survey data from guardians of 2,536 dogs fed either conventional meat, raw meat, or vegan diet. The survey asked guardians about the dogs’ health, including the number of veterinary visits, use of medications, and specific dog health disorders. Statistical analysis of the survey results suggested that, overall, dogs on conventional diets were less healthy than dogs on raw meat or vegan diets. 

Andrew Knight (professor at the University of Winchester, UK), Eason Huang (independent consultant from Australia), Nicholas Rai (from Menzies Health Institute in Queensland), and Hazel Brown (from the Centre for Animal Welfare at the University of Winchester), published these findings in the open-access journal PLOS ONE on 13th April 2022, in the article titled “Vegan versus meat-based dog food: Guardian-reported indicators of health.”

These researchers found that the percentage of dogs reported to have suffered from health disorders was 49% for the conventional diet, 43% for the raw meat diet and 36% for the vegan diet. A different 2021 study concluded that dogs found plant-based dog food just as tasty as conventional meat-based dog food.

The authors said: “Our study of 2,536 dogs is by far the largest study published to date, exploring health outcomes of dogs fed vegan and meat-based diets. It analysed a range of objective data, as well as owner opinions and reported veterinary assessments of health. It revealed that the healthiest and least hazardous dietary choices for dogs, are nutritionally sound vegan diets.”

Prof Knight said to the Guardian: “One of the most common health problems for dogs is being overweight or obese and it is unfortunately common that when we do tests on the commercial meat-based diets, there are more calories…We also know the health hazards associated with overconsumption of meat and dairy for people and it’s often the same ingredients.”

Initially, dogs on raw meat diets appeared to be healthier than those on vegan diets, but the researchers noted several factors that prevent a conclusion that raw meat diets are healthier, such as dogs on raw meat diets in this study were significantly younger than dogs on vegan diets (which made them more likely to have fewer health issues) and some research suggests that guardians of dogs on raw meat diets are less likely to take their dogs to a veterinarian. Prior research has linked raw meat diets to increased risk of pathogens and nutritional deficiencies, so the researchers suggest that a nutritionally sound vegan diet may in fact be the healthiest and least hazardous choice for dogs. It would be interesting to see a similar study on vegan cat food, to confirm the most recent ones that also point towards similar conclusions. 

“Originally from Catalonia, but resident in the UK for several decades, Jordi is a vegan zoologist and author, who has been involved in different aspects of animal protection for many years. In addition to scientific research, he has worked mostly as an undercover investigator, animal welfare consultant, and animal protection campaigner. He has been an ethical vegan since 2002, and in 2020 he secured the legal protection of all ethical vegans in Great Britain from discrimination in a landmark employment tribunal case that was discussed all over the world. He is also the author of the book, ‘Ethical Vegan: a personal and political journey to change the world’.