Can Dogs Be Vegetarian? The Science, the benefits and how to do it properly

The rise in plant-based eating for humans has naturally led pet owners to wonder: can dogs be vegetarian? The answer isn’t a simple yes or no—it’s a question that deserves a thorough look at canine nutritional science, amino acid profiles, and individual health needs. In this article, we’ll dive deep into the evidence, protein sources, and practical solutions for feeding dogs a balanced vegetarian diet.

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Are Dogs Carnivores or Omnivores?

Let’s start with some biological facts. Dogs (Canis lupus familiaris) are facultative carnivores—meaning they prefer animal protein but are biologically capable of digesting and obtaining nutrients from plant-based foods. According to a landmark study published in Nature (Axelsson et al., 2013), dogs have evolved more copies of genes involved in starch digestion compared to their wolf ancestors, suggesting an adaptation to an omnivorous diet.

The Importance of Amino Acids for Dogs

Whether a diet is meat-based or vegetarian, amino acid balance is non-negotiable. Dogs require ten essential amino acids that must be supplied through diet:

• Arginine

• Histidine

• Isoleucine

• Leucine

• Lysine

• Methionine (and cysteine as a secondary requirement)

• Phenylalanine (and tyrosine)

• Threonine

• Tryptophan

• Valine

Animal proteins naturally provide a complete amino acid profile. However, vegetarian sources require careful combination. For example:

• Soy is rich in lysine but lower in methionine.

• Rice is high in methionine but lower in lysine.

• Peas and lentils offer good protein but require blending for balance.

A study published in the Journal of the American Veterinary Medical Association (Dodd et al., 2019) reviewed vegetarian and vegan diets for dogs and found that when properly formulated, they can meet nutritional standards set by AAFCO and FEDIAF.

Best Vegetarian Protein Sources for Dogs

If you’re considering a vegetarian diet for your dog, these protein sources are commonly used in balanced recipes:

• Eggs (lacto-vegetarian diets)

• Cottage cheese and yoghurt (lacto-vegetarian)

• Soybeans and tofu

• Lentils, chickpeas, and peas

• Quinoa

• Pumpkin seeds and chia seeds

Which Dogs Might Benefit from a Vegetarian Diet?

A meat-free diet isn’t suitable for every dog. However, some dogs may thrive on vegetarian meals under expert guidance:

• Dogs with food allergies: Many dogs are allergic to common proteins like beef, chicken, or lamb. A vegetarian or novel plant-protein diet can help manage food sensitivities (Picco et al., 2008).

• Dogs with liver disease: In some cases, plant-based proteins can be lower in ammonia production, supporting liver function (Center, 2007).

• Dogs prone to urate or cystine stones: Vegetarian diets are lower in purines and can help prevent recurrence (Bartges, 2016).

• Dogs in households following ethical vegetarianism: Provided nutritional needs are fully met, dogs can be maintained on such diets (Knight & Leitsberger, 2016).

Note: Dogs with certain heart conditions (like dilated cardiomyopathy) require extra caution with grain-free and pulse-heavy diets. Always work with a qualified canine nutritionist.

Peer-Reviewed Research Supporting Vegetarian Diets in Dogs

• Dodd, S.A.S., et al. (2019): "Plant-based (vegan) diets for pets: A survey of pet owner attitudes and feeding practices". JAVMA, 254(11), 1306-1313. https://doi.org/10.2460/javma.254.11.1306

• Knight, A., & Leitsberger, M. (2016): "Vegetarian versus Meat-Based Diets for Companion Animals". Animals, 6(9), 57. https://doi.org/10.3390/ani6090057

• Axelsson, E., et al. (2013): "The genomic signature of dog domestication reveals adaptation to a starch-rich diet". Nature, 495, 360–364. https://doi.org/10.1038/nature11837

Don’t DIY Without Expert Help!

While vegetarian diets can work for dogs, they require careful formulation to avoid deficiencies in:

• Taurine

• L-carnitine

• Vitamin B12

• Iron and zinc (plant forms are less bioavailable)

• Omega-3 fatty acids (EPA and DHA)

At The Canine Code, our expert-led membership includes fully balanced, vet-checked recipes and guidance for owners looking to explore plant-forward diets safely. Whether your goal is to manage allergies or align your dog's diet with your family’s ethics, we’re here to support you.

Final Thoughts: Can Dogs Be Vegetarian?

Yes, dogs can be vegetarian—with important caveats. A vegetarian diet for dogs must be carefully balanced to provide all essential amino acids, vitamins, and minerals. Done right, it can help some dogs with allergies, liver disease, or urinary conditions. Done wrong, it can lead to serious deficiencies.

For those serious about exploring this path, professional formulation and ongoing monitoring are key.

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If you need personalised advice regarding your dog’s diet or health, feel free to reach out to The Canine Dietitian at www.thecaninedietitian.co.uk. Or click here for a FREE diet assessment. We’re here to help ensure your dog gets the best nutrition possible!