Can Dogs be Vegan (or Vegetarian) And Healthy?
No matter your reasons for exploring the option of feeding your dog vegan dog food, two questions will dominate. Will they like it? Is it healthy for them?
To many, feeding a dog a meat-free diet is considered unnatural and depriving them of pleasure at mealtime.
The most important aspect of any diet, yours or your dog’s, is to ensure that you both get the correct balance of ALL the nutrients needed to thrive. Enjoying those meals is also a very important factor.
Let’s start with the unnatural and enjoyment question first.
Do Dogs Have a Preference for Meat?
A study published in the Journal of Ethology concluded that pups do not have an innate preference for meat and that any preference for meat is likely a learned behaviour.
A further study, published in Frontiers of Veterinary Science, found that dogs fed a novel diet, either meat or plant-based, experienced neophobia initially, however dogs did not show a preference for either the animal or vegetable ingredient-based diets.
Research published in Animal Feed Science and Technology found that that dogs demonstrated a preference for diets containing soybean meal, rather than diets containing poultry offal meal.
A 2021 study by Dr Andrew Knight published on PLOS One indicated that vegan pet foods are at least as palatable to dogs (and cats) as conventional meat-based kibble, wet food or raw meat diets.
Are Plant-based Ingredients Nutritionally Appropriate for Dogs?
As is highlighted in the Science of Nutrition section on our site, your dog needs the correct balance of high-quality nutrients – proteins, fats, carbohydrates, minerals, and vitamins – which they can get from either meat or plants.
It is the balance, completeness and bioavailability of these nutrients which is most important for their thriving health.
The digestibility of any food your dog eats is vitally important. Digestion is the way your dog’s body breaks down food in their gut, extracting the macro and micronutrients and passing them into their bloodstream for use in maintaining, and improving, their health.
As a highly digestible food provides a higher proportion of absorbed nutrients than a less digestible food, digestibility provides an important measure of a food’s nutritional value and quality.
Can Dogs Digest Plant-based Ingredients?
Dogs’ diets and their physiology has developed in remarkably similar fashion to our own over more than 27,000 years. As they evolved from wolves to ‘domesticated’ dogs, and we moved from being hunters and gatherers to farmers some 5-7,000 years ago, so their genetic makeup evolved.
Evolutionary scientist Erik Axelsson and his colleagues at Uppsala University in Sweden discovered in this research piece published in 2013, that dogs have four to 30 copies of a gene, AMY2B, that allows them to digest starchy (plant-based) foods. Wolves typically only have two copies.
His colleague, Maja Arendt’s research published in 2014 in Animal Genetics, confirmed the ability of dogs to digest starchy, plant-based ingredients due to the drastic increase in copy numbers of the gene coding for pancreatic amylase, AMY2B.
Their findings are corroborated by Morgane Ollivier’s 2016 research published in the Royal Society Publishing.
These previous studies surmised that dogs do not express salivary amylase, AMY1, however recent research, published in the National Library for Medicine, shows that several dog breeds do in fact express substantial amounts of this salivary amylase enzyme.
This means that as our dogs’ diets have changed so their genetic makeup has evolved, in similar fashion to humans’, to improve their ability to efficiently derive nutrients from plant-based foods.
Digestibility of Grains and Other Starches for Dogs.
As highlighted previously, the level of digestibility of ingredients in the food our dogs eat is important as it determines the extent to which nutrients are available for their overall health.
Research conducted by Murray and colleagues, published in 1999, looked at the digestibility of six high-starch flours as the main source of carbohydrate and included barley, corn, potato, rice, sorghum, and wheat. The findings, almost complete digestibility (>99%) for all ingredients.
A subsequent research piece by Carciofi and colleagues in 2008, on the digestibility of six starch sources – cassava flour, brewer’s rice, corn, sorghum, peas or lentils – found that starch digestibility was >98%.
Cara Cargo-Froom, Anna Kate Shoveller and M.Z. Fan of University of Guelph published a study investigating the digestibility of minerals in animal and vegetable ingredient based dog food in 2017. Their findings – digestibility of the minerals Calcium, Phosphorous and Iron were greater in dogs fed diets that are largely vegetable based, and no different for Potassium, Copper and Zinc. Concluding that digestibility of endogenous minerals is similar, or greater, in dogs fed diets that are largely vegetable based.
In 2021, Amr Abd El-Wahab, Volker Wilke, Richard Grone and Christian Visscher published research on the nutrient digestibility of various vegetarian dog foods and concluded that the digestibility of organic matter, crude protein, crude fat and N-free extract were not affected for any of the diets.
Research conducted by the Department of Animal Sciences, University of Illinois into the ‘Use of Legumes and Yeast as Novel Dietary Protein Sources in Extruded Canine Diets’ concluded that inclusion of these novel, plant-based, protein sources (of chickpeas, lentils, peanut flour and yeast) showed no detrimental effects on nutrient digestibility or faecal characteristics and represent viable protein sources in canine diets that can produce beneficial shifts in faecal metabolites.
A further study, published on PLOS ONE in 2021, showed that digestibility of proteins, fats and starches were not different between chicken based and 100% plant-based foods.
Can Dogs Maintain Health and Thrive on a Vegan Diet?
Possibly the question we all most want answered – ‘Will my dog be as healthy if they don’t have meat in their diet?’
Anecdotally the answer is unequivocally, yes.
One of the oldest lived dogs, Bramble, lived to the ripe old age of 27 years and 211 days and was fed on a vegan diet of lentils, textured vegetable protein, and brown rice, with some extra vegetables and fruit thrown in occasionally! Bramble was part of an 8-dog family, all fed a vegan diet, and in addition to her 27-year long life, three lived to be 19 and one lived to be 20!
Vegan Dog Food Research Studies on Health and Longevity
There is a growing body of evidence that like us, our dogs’ health and longevity is best served by a diet that limits meat and favours plant based.
A 2009 study by Brown et al, An experimental meat-free diet maintained haematological characteristics in sprint-racing sled dogs, explored vegan diets in dogs that have some of the highest energy needs: sprint-racing huskies.
The study compared the health of twelve sled racing dogs — six fed a nutritionally balanced meat-free diet, and the other six a commercial meat-based diet.
“Haematology results for all dogs, irrespective of diet, were within normal range throughout the study and the consulting veterinarian assessed all dogs to be in excellent physical condition.” None of the dogs developed anaemia — on the contrary, red blood cell counts and haemoglobin values increased significantly over time in both groups.
Subsequent research, Vegan nutrition of dogs and cats, by Pia-Gloria Semp at the University of Veterinary Medicine in Vienna was conducted with 174 dogs exclusively fed a vegan diet for a minimum of 6 months. The average duration of exclusively vegan fed dogs was 2.83years.
Physical examinations and clinical tests revealed those fed on a vegan diet did not display any irregularities connected to nutrition. Blood tests showed that all dogs who were examined had proteins within normal levels.
None of the tested parameters showed any difference or deviation compared to the results of dogs fed conventional meat-based food. Most importantly, no low levels of iron or vitamin B12 were detected in dogs fed vegan food.
A study, ‘Plant-based diets for dogs ’ investigating the nutritional adequacy of plant-based diets for dogs by Dodd et al from the Department of Clinical Studies, Ontario Veterinary College, University of Guelph concluded the following in their clinical summary
‘Dogs have dietary requirements for energy and essential nutrients, but they do not have a recognized requirement for animal-derived ingredients per se. In accordance with the current understanding of pet nutrition, any diet that meets or exceeds the minimum nutrient requirements of a dog for a specific life stage would be considered nutritionally sufficient for that animal, regardless of ingredients. However, special care must be taken when formulating plant-based diets to ensure that all nutrient requirements are met, particularly requirements for concentrations of total protein, methionine, taurine, DHA, and vitamins A, B12, and D because these nutrients are typically obtained from animal-based ingredients.’
Madelaine Leitsberger and Professor Doctor Andrew Knight’ research piece, Vegetarian versus Meat-Based Diets for Companion Animals, published in 2016 concluded in summary, ‘a significant and growing body of population studies and cases suggest that cats and dogs may be successfully maintained on nutritionally sound vegetarian diets long-term, and indeed, may thrive. Such diets have been associated with benefits such as improved coat condition, allergy control, weight control, increased overall health and vitality, arthritis regression, diabetes regression’.
The largest study to date on the health effects of vegan vs meat based diets for dogs, Vegan versus meat-based dog food: Guardian-reported indicators of health, was published in 2022 by Andrew Knight et al.
The study assessed the diets of 2536 dogs of whom 1370 were fed a conventional meat based diet, 830 a raw meat diet and 336 a vegan diet and concluded, ‘Percentages of dogs in each dietary group considered to have suffered from health disorders were 49% (conventional meat), 43% (raw meat) and 36% (vegan). Significant evidence indicates that raw meat diets are often associated with dietary hazards, including nutritional deficiencies and imbalances, and pathogens. Accordingly, the pooled evidence to date indicates that the healthiest and least hazardous dietary choices for dogs, are nutritionally sound vegan diets.’
A research piece, Owner perception of health of North American dogs fed meat- or plant-based diets, published in 2022 by Sarah Dodd et al at the Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Canada.
Results showed that owners feeding plant-based diets to their dog reported fewer health disorders, specifically with respect to ocular (sight) or gastrointestinal (digestive) and hepatic (liver) disorders. Dog longevity was reported to be 1 year and 7 months (more than 1.5 years) greater for dogs fed plant-based diets. Owners feeding plant-based diets to their dogs relied less on veterinary associates for nutrition information, versus dog owners feeding meat-based diets.
The British Veterinary Association’s (BVA) view on feeding your dog a vegan/meat-free/plant-based diet is ‘While it is theoretically possible, the British Veterinary Association does not recommend giving a dog a vegetarian or a vegan diet as it is much easier to get the balance of essential nutrients wrong than to get it right.’ This is true but it is also very true of meat-based diet formulation.
A 2017 study by M. Davies et al of 177 popular meat-based (animal and fish) ‘complete’ pet foods sold in UK supermarkets, ranging from ‘supermarket own-brand’ food to ‘prescription/veterinary/therapeutic’ diets, concluded “This study highlights broad non-compliance of a range of popular pet foods sold in the UK with EU guidelines (94% and 61% of wet and dry foods, respectively). If fed exclusively and over an extended period, a number of these pet foods could impact the general health of companion animals”. Only 6% (6/97) of wet and 38% (30/80) of dry foods were fully compliant with EU petfood standards.
It is vital that our dog’s food contains all the nutrients it requires in the correct balance at a bare minimum and many meat-based foods have been found wanting.
They also add, ‘“Our advice to pet owners interested in exploring alternative diet options for their pets is to talk to their vet first, as any changes to a pet’s diet should only be undertaken under advice of a vet with in-depth nutritional knowledge.” The unfortunate fact is that most vets do not possess this in-depth nutritional knowledge. There are approximately 200,000 vets in the EU of whom less than a 100 are ECVCN (EBVS® European Specialist in Veterinary and Comparative Nutrition) registered – the qualification necessary to offer such in-depth nutritional knowledge.
The latest, and longest lasting, study on the effects of a vegan diet on dogs’ health was published in 2023 by Annika Linde et al from WesternU College of Veterinary Medicine Office for Research and concluded that after a year of feeding a plant-based diet’ ….that clinically healthy adult dogs maintain health when fed a nutritionally complete, commercially available, plant-based diet with pea protein as a main ingredient over a twelve-month period.’
Vets, Canine Nutritionists and Animal Nutrition Academics on Vegan Dog Food
There is an increasing amount of research of not only the appropriateness of vegan dog food but also the many health-giving benefits plant-based food offers our dogs.
Following are the views of a number of highly qualified and well-respected veterinary professionals and scientists.
Dr. Sarah Dodd BVSc, MSc, PhD, DECVCN Board-certified Veterinary Nutritionist
‘…there are a lot of dogs that have dietary hypersensitivities and allergies to those common protein sources that are used so ubiquitously within the pet food industry’
‘..therapeutic diets that are entirely plant-based and they’re used particularly for dietary hypersensitivities or we’ll use them if we have hyperlipidaemia or they can be really great for animals with liver compromise as well because they have a nicer gentler amino acid profile’
‘… there are some instances where we actually, for therapeutic reasons, want the animal to be on a plant-based diet’
“We know that plant-based food contains a lot more antioxidants. So that’s a good thing because that’s going to help convert these cells to, to more normal, healthy cells”
“And we know that a plant-based diet can help dogs live longer and stay generally more healthy. And we have published evidence to support that.”
“So therefore, yes, plant-based feeding could stop cancer in dogs.”
Dr. Greg Aldrich, PhD – Nutrition Sciences Research Associate Professor at Kansas State University
‘It IS possible to produce balanced vegetarian/vegan dog diets’
‘…. they can be nutritionally complete and balanced with a bit of diligence’
Dr. Guy Sandelowsky BSc. BVet Med Sci. BVM BVS MRCVS
“It’s well known in humans to watch the amount of processed meat we eat as it can negatively affect our health with problems like obesity and cancer, but for our four-legged friends we often don’t do the same.”
“Lots of dog parents who have switched their dogs to a plant-based diet tell me that they see huge improvements in their dogs’ health and wellbeing. They remark on increased energy levels, shinier coats and better stools.”
“Even if you don’t feel ready to go fully plant-based yet, maybe try going flexitarian and switching out a meat-based meal a day for a plant-based one, every little bit helps.”
Dr. Kelly Swanson, Professor of Animal and Nutritional Sciences, University of Illinois
‘Although dogs and cats have unique metabolic and nutrient requirements (e.g., protein, arginine, taurine, arachidonic acid, vitamin A, vitamin D, niacin), these targets may be reached with a wide variety of ingredient sources’
‘Dogs have nutrient requirements, not ingredient requirements.’
Dr. Lorelei Wakefield VMD, University of Pennsylvania School of Veterinary Medicine
“All dogs can benefit from a vegan diet. Thanks to ten thousand years of evolution alongside humankind, dogs are now physiologically omnivores. This means they can thrive on a nutritionally balanced plant-based food”
Dr. Richard Pitcairn DVM, Academy of Veterinary Homeopathy
“I am an advocate for emphasizing a plant-based diet for dogs and cats for reasons of health, ethics and resource concern. Many of the chronic health problems in both dogs and cats are effects of eating other animals which have accumulated many environmental toxins, or that have been given drugs or other substances.”
Dr. Andrew Knight BSc (Vet Biol), BVMS, CertAW, MANZCVS, DipWCAWBM (AWSEL), DACAW, PhD, MRCVS, SFHEA
“Both cats and dogs may thrive on vegetarian and vegan diets, but these must be nutritionally complete and reasonably balanced.”
“As an ethical veterinarian, I have a responsibility to recommend foods for my patients that are balanced and healthy. As an ethical vegan, I have a responsibility to promote compassion to all animals, not just my patients.”
Dr. Marybeth Minter DVM, Colorado State University. Mariposa Veterinary Service, Kanab, UT
“After seeing the livestock industry in action, and coming from a place of compassion, health and environmental concern, I am an advocate of feeding a plant-based diet for dogs and cats. Many of my patients have attained improved health with a plant-based diet alone.”
Dr. Jena Questen DVM, CertAqV, Aspen Park Vet Hospital
“Why do I support a vegan diet for dogs? Because the science is clear: 1) Humans and dogs are both omnivores, 2) A plant-based diet is the best diet for health and longevity for humans, and 3) I want my animals to live as long, and healthy, as possible, therefore a plant based diet is what I feed and recommend, with tremendous results!”
‘Dogs and cats have dietary requirements for energy and essential nutrients, but they do not have requirements for specific ingredients, no matter if these ingredients are animal-derived, plant-derived or synthetic.’
“As a veterinary nutritionist, I use meat-free diets quite a bit to help manage various health concerns.”
Dr Joanna Woodnutt BVM BVS BVMedSci MRCVS University of Nottingham
‘Vegan dog food is fairly new in the world of dog food nutrition, and many vets and pet owners are still a little cautious about feeding it, especially with dogs sitting right on the line between carnivore and omnivore. However, there are some great vegan diets out there that are complete and balanced and might be worth a try.’
Can Dogs Stay Healthy On A Vegetarian Diet?
‘The answer is yes — dogs can eat a vegetarian diet and thrive.’
‘It is true that dogs belong to the order Carnivora, but they are actually omnivores. The canine body has the ability to transform certain amino acids, the building blocks or protein, into others, meaning that dogs can get all the amino acids they need while avoiding meat.’
‘Thankfully, dogs are very good at converting some types of amino acids into others. When used in the right combination, ingredients like beans, soybeans, sweet potatoes, peas, chickpeas, lentils, quinoa, rice, and whole grains can supply dogs with all their essential amino acids.’
‘The only issue I’ve seen with dogs being switched to a vegetarian food is one of acceptance. It seems to me that dogs who are used to eating diets that contain meat go through a “where’s the beef, chicken … etc.?” stage. Overcoming this is easy if you simply mix increasing amounts of the new food in with decreasing amounts of the old and make the change slowly.
So, if feeding meat to your dog presents an ethical quandary for you, options are available.’
Dr. Lisa Weeth, DVM, DACVN®, Head of Nutrition Department Metropolitan Animal Specialty Hospital
“I don’t have a problem with transitioning their healthy, adult dog onto a vegan or vegetarian diet as long as it is balanced for their life stage and balanced for a healthy adult. At the end of the day, if we’re meeting all of the individual animal’s needs, then we have a lot of flexibility in what we can feed them.”
“For dogs with things like pancreatitis or high triglyceride levels, they may do better on a moderate fat vegan or vegetarian diet.”
A vegan diet may be a good option for your dog if she needs to avoid animal proteins.
“For example, with kidney disease, urate bladder stones and inflammatory bowel disease (IBD).”
However, the most compelling ‘evidence’ that a vegan diet is nutritionally complete for our dogs is that many large meat-based dog food brands are now adding plant-based options to their stable to commercially capitalise on the increasing numbers of families looking to feed their dog a plant-based diet. Were these diets inadequate nutritionally in any way, this would not be the case.
The most recent endorsement that plant-based, or vegan diets, for dogs are appropriate was released in February 2023 by UK Pet Food (previously known as the Pet Food Manufacturers’ Association or PFMA), whose members account for over 90% of the pet food market and are responsible for feeding the nation’s wide range of pets.
They state ‘ Dogs are omnivorous carnivores which means that they can digest and utilise both animal- and plant-based ingredients. Their physiology can adapt to a well-balanced and carefully formulated vegetarian or vegan diet, given their individual circumstances.’ Get their factsheet on vegan dog food.
Bonza vegan, plant-based dog food has been tested for nutritional completeness and balance at the Veterinary Faculty, Complutense University of Madrid, one of Europe’s leading veterinary institutions.
