Can a dog stay healthy on an entirely plant-based diet? This question has long sparked debate among dog guardians, veterinarians and animal nutrition experts.

In recent years, a growing number of scientific studies have explored the effects of vegan diets on dogs' health. Some have examined their overall health, while others have investigated the digestibility of plant-based ingredients, the nutritional adequacy of diets or changes in blood parameters.

The findings are encouraging. They suggest that a properly formulated plant-based diet can meet dogs' nutritional needs. However, researchers also emphasise the need for more high-quality, long-term evidence.

So, what do we actually know today?

Do Dogs Need Meat to Stay Healthy?

Over the course of evolution, dogs have adapted to diets containing both animal and plant-based ingredients. Compared with wolves, they have also developed adaptations that allow them to make more efficient use of starch.

When it comes to nutrition, however, it is important to distinguish between ingredients and nutrients.

To stay healthy, dogs need adequate amounts of protein, essential amino acids, fatty acids, vitamins and minerals. They do not necessarily need meat as a specific ingredient, provided they receive all the nutrients they require from other carefully selected and appropriately supplemented sources.

This does not mean that every plant-based food is suitable for dogs. Its formulation must meet their nutritional requirements, while nutrient digestibility and bioavailability are equally important.

What Does Research Tell Us About the Health of Vegan-Fed Dogs?

A Study of 2,536 Dogs: Encouraging Findings, but Important Limitations

One of the most widely discussed studies was published in 2022, followed by a further analysis in 2024.

Researchers led by Andrew Knight analysed data from 2,536 dogs that had been fed one of three types of diet for at least a year: conventional meat-based food, raw meat-based food or vegan food.

Dog guardians answered questions about their dogs' health, veterinary visits, medication use and other health indicators.

Health problems were reported in:

  • 49% of dogs fed conventional meat-based diets,
  • 43% of dogs fed raw meat-based diets,
  • 36% of dogs fed vegan diets.

The findings were therefore favourable for the group of dogs fed vegan diets.

However, it is important to emphasise that most of the information came from reports provided by dog guardians. Such studies can offer valuable insights, but their results may be influenced by differences between groups, reporting practices and other factors.

We therefore cannot conclude from these findings that a vegan diet itself improves health or prevents disease.

Source: Knight, Bauer & Brown (2024), Vegan versus meat-based dog food: Guardian-reported health outcomes in 2,536 dogs, after controlling for canine demographic factors.

A One-Year Study: Health Indicators Remained Stable

Another study, published in 2024, followed 15 healthy adult dogs over a year while they were fed a commercial plant-based diet.

Rather than relying solely on observations from dog guardians, the researchers conducted veterinary examinations and laboratory tests. These included blood counts, biochemical parameters, amino acids, vitamins and certain indicators of heart health.

After twelve months, the dogs had maintained good health according to the parameters monitored.

This is an important finding because the study included objective health measurements over an extended period.

Nevertheless, only 15 dogs participated, and the study did not include a parallel control group receiving meat-based food. Its findings therefore cannot be generalised to all dogs or all vegan products.

Source: Linde et al. (2024), Domestic dogs maintain clinical, nutritional, and hematological health outcomes when fed a commercial plant-based diet for a year.

Can Dogs Digest Plant-Based Proteins Effectively?

One common concern about vegan diets for dogs is that they cannot digest plant-based proteins efficiently enough.

However, scientific research presents a more nuanced picture.

A Comparative Study Involving 61 Dogs

A 12-week study involved 61 adult dogs fed either a plant-based or a meat-based diet. Due to the availability of samples and data, the digestibility analyses included smaller groups of dogs.

The researchers found no statistically significant differences between the diets in the digestibility of protein, fat or dry matter.

These results suggest that a properly formulated plant-based food can achieve digestibility comparable to that of meat-based food.

Source: Liversidge et al. (2023), Extruded diet macronutrient digestibility: plant-based (vegan) vs. animal-based diets.

A Review of Research Published in 2026

In 2026, Andrew Knight published a review of scientific literature examining the digestibility of vegan and vegetarian diets for dogs and cats.

The review covered 31 studies, including 22 focusing on dogs.

The findings suggest that many plant-based ingredients and properly formulated plant-based diets can be highly digestible. In studies directly examining the digestibility of complete plant-based diets, protein digestibility exceeded 80%.

Importantly, digestibility depends on more than whether a protein comes from a plant or an animal. The choice of ingredients, processing methods and the composition of the complete diet also play a role.

Source: Knight (2026), The Digestibility of Vegan and Vegetarian Diets for Dogs and Cats.

What About Vitamins, Minerals and Other Essential Nutrients?

A highly digestible food is not necessarily nutritionally complete.

For a dog to remain healthy, its daily diet must provide all essential nutrients in appropriate amounts and proportions.

When formulating plant-based dog food, particular attention should be paid to protein quality and amino acid composition, certain B vitamins, vitamin D, calcium, phosphorus, zinc and appropriate fatty acids.

Depending on the diet's composition and the individual dog's needs, it may also be important to monitor nutrients associated with heart health, such as taurine and L-carnitine.

A 2026 Review of 54 Studies

A systematic review published in 2026 analysed 54 scientific studies investigating the nutritional adequacy of commercial dog and cat foods.

In 44 of these studies, the authors identified at least some deviations from nutritional recommendations.

Importantly, these deviations were found not only in vegan foods but also in different types of animal-based pet food.

This does not mean that most pet foods on the market are nutritionally inadequate. Rather, it highlights the importance of careful formulation, manufacturing quality control and nutritional testing across all types of pet food.

Source: Mace, Nicholles & Knight (2026), How Nutritionally Sound Is Commercially Available Vegan Pet Food Relative to Meat-Based Pet Food? A Systematic Review.

What Does Research Show About Metabolism and Other Health Indicators?

Researchers are also investigating how plant-based diets affect metabolism, body composition, vitamin status and the gut microbiome.

In a three-month randomised trial involving 61 healthy adult dogs, researchers compared plant-based and meat-based diets, examining vitamin D metabolism and bone health among other parameters.

Dogs in both groups maintained the monitored indicators of health and body composition. Some forms of vitamin D in the blood changed in dogs fed the plant-based diet, while total vitamin D concentrations remained adequate. The researchers found no deterioration in bone mineral density.

These findings are encouraging, although a three-month study cannot answer every question about the effects of feeding a plant-based diet over several years.

Source: Dodd et al. (2023), Efficacy of vitamin D2 in maintaining serum total vitamin D concentrations and bone mineralisation in adult dogs fed a plant-based (vegan) diet in a 3-month randomised trial.

Are Dogs on Vegan Diets Healthier?

This is a question that requires particular care.

Some observational studies have reported more favourable health indicators among dogs fed vegan diets. However, this does not prove that the type of diet itself caused these differences.

A dog's health is influenced by many factors, including age, breed, genetics, body weight, physical activity, living conditions and the quality of veterinary care.

At present, there is therefore insufficient reliable evidence to conclude that vegan diets generally extend dogs' lives or prevent particular diseases.

What we can say is that the available findings for properly formulated plant-based diets are encouraging, and several studies have found no significant deterioration in the health indicators they monitored.

What Do Systematic Reviews of Scientific Research Say?

Individual studies can provide interesting findings, but understanding the bigger picture requires examining the evidence as a whole.

A systematic review published in 2023 analysed 16 studies investigating the effects of vegan diets on the health of dogs and cats.

The authors found no convincing evidence of major adverse health effects associated with vegan diets. They also identified some possible benefits.

At the same time, they noted that the certainty of most available evidence was low or very low. Many studies were short, involved relatively few animals or relied on reports from their guardians.

This means that a lack of observed harmful effects is not the same as proof of complete long-term safety.

Source: Domínguez-Oliva et al. (2023), The Impact of Vegan Diets on Indicators of Health in Dogs and Cats: A Systematic Review.

What Should You Look for When Choosing Vegan Dog Food?

Scientific findings are most useful when we can apply them to everyday care.

If you are considering a plant-based diet for your dog, there are a few important points to keep in mind:

  • Choose complete dog food. For everyday feeding, look for food labelled as complete and suitable for your dog's life stage.
  • Consider the manufacturer. Give preference to manufacturers that formulate their foods according to established nutritional guidelines and verify their nutritional adequacy.
  • Make the transition gradually. Introduce the new food over time, monitoring your dog's digestion, appetite and general well-being.
  • Consider individual needs. Puppies, pregnant or nursing dogs, and dogs with certain medical conditions require specially tailored nutrition.
  • Monitor your dog's health. Regular veterinary check-ups are important regardless of diet. If your dog has particular health risks, discuss whether additional tests may be appropriate with your veterinarian.

Extra care is needed with homemade vegan diets. Without a recipe formulated by a qualified veterinary nutrition professional, it can be difficult to achieve the correct balance of all essential nutrients.

What Do We Still Not Know About Vegan Diets for Dogs?

Although the number of studies continues to grow, several important questions remain unanswered.

We particularly need more long-term studies involving larger numbers of dogs, comparisons between different commercial products and evidence about the effects of plant-based diets at different life stages.

There is also insufficient high-quality evidence to reliably compare the long-term incidence of specific diseases or the life expectancy of dogs fed different types of diets.

Science develops gradually. New findings build on existing knowledge and sometimes change how we understand particular questions.

Conclusion

Scientific research suggests that a properly formulated vegan diet can be a suitable option for dogs. Plant-based ingredients can provide important nutrients, while studies examining digestibility and health outcomes have produced encouraging findings.

At the same time, it is important to pay attention to food quality and recognise the limitations of current research.

The most important question is not simply whether a food contains meat, but whether it provides all the nutrients a dog needs and suits their individual requirements.

At Taffy Lilly, we believe in thoughtful choices based on knowledge, responsibility and care for animals. That is why we continue to follow new scientific research and developments in plant-based nutrition for dogs with great interest.