Nowadays, there is a wide variety of pet food options available to the average consumer. From traditional kibble diets all the way to homemade raw, pet owners have endless options to choose from. The abundance of options is often overwhelming, and the choice is not made any easier with the amount of misinformation surrounding each diet. We’ve all heard the pros and cons of raw pet food, but what about vegan and vegetarian? Do these new plant-based diets have a place in our pup’s bowls, or are we doing our canine companions a disservice by even humoring them?
Although I respect people’s decisions to go vegetarian or vegan themselves, I’ve got a bone to pick with vegan and vegetarian dog food. Though I already feed raw and think it’s the most species-appropriate diet available (based on hours of personal research), let’s take a deep dive into the world of plant-based pet food together - what it’s made of, the nutritional science behind it, and whether or not it’s a good option for the average dog.
Vegan means no animal products - no eggs, dairy, meat, etc. Vegetarian means no meat - other things that come from animals are typically okay. The average dog food contains fresh meats or meat meals, some specialty foods may include eggs, and a couple popular dairy supplements are goat milk and kefir! High quality kibbles typically include fresh meat as their first ingredient with a few grains or vegetables towards the bottom of the list for added vitamins and minerals, and to act as a binder. In comparison, vegan and vegetarian dog food are made up primarily of legumes and grains, with a little bit of fruits and veggies, and a whole lot of added synthetic vitamins and minerals.
It’s important to note that dogs are not wolves and they are capable of digesting and benefiting from fruits, vegetables, and grains. Despite this, there is clear evidence that their digestive systems haven’t evolved to the point where it makes sense to recommend a vegan/vegetarian diet as beneficial for the average dog. Let me explain.
Protein and Your Pup. Protein is probably the single most important part of any dog’s diet (aside from healthy fats), so it’s important to know where it’s coming from (the source) and how it is used by your dog. Essentially, protein gets broken down into amino acids that each play a specific role in your dog’s body and contribute to healthy functioning. Protein can come from a variety of foods (including plants), but the highest concentrations of proteins are typically found in animal-based foods. Take for example the amount of protein found in 100 grams of potatoes and 100 grams of eggs - the potatoes only contain 2 grams of protein, while the eggs contain 13 grams - what a big difference! The lack of protein in plants means a wider variety of vegetarian/vegan protein sources need to be combined in order to provide the full spectrum of essential amino acids, and even this can be difficult to accomplish as plants have vastly different amino acid profiles compared to meats and other animal products. Additionally, because of the lack of protein in plants compared to meat, you will have to feed a much larger amount of food for your dog to get all the necessary nutrients - on average, as much as an entire extra cup a day compared to high quality meat-based foods!
Carbs and Digestibility. Now that we know how protein is used by your dog, it’s important to look at what the abundance of plant-based ingredients means for digestibility. Dogs are primarily carnivores - they have sharp and pointed teeth designed to cut through meat, jaws designed for vertical chewing (not grinding), and they lack amylase (an enzyme that breaks down carbs) in their saliva. Yet through years of evolution, they have become somewhat omnivorous. Dogs are capable of digesting and even benefiting from things like fruits, veggies, and grains - the complex part comes when we ask “what” and “how much?”
Fruits and veggies have lots of benefits for dogs - for example, blueberries and raspberries are full of antioxidants and fiber, while vegetables like spinach and kale provide lots of healthy vitamins and minerals. It would be a lie to tell you that dogs should ONLY eat meat - fruits and veggies help fill in gaps when it comes to micronutrients, and are often included in both kibbles AND raw diets. Unfortunately, some of the most popular ingredients in kibble today are legumes (i.e., chickpeas, peas, potatoes) - starchy, complex carbs that require extra pancreatic enzymes to digest before they can be used by your dog. The carbs are broken down into sugars, and any excess gets stored as fat. And while this may not seem bad at first, remember that dogs have no nutritional requirement for carbohydrates, and having too many in the food could contribute to weight gain (similar to what it does to people).
Additionally, dogs have a harder time extracting protein from their food if it lacks meat simply because plants have less protein bioavailability compared to meats. What this means is that even if a food says it has 25% crude protein in the guaranteed analysis, the amount of protein your dog is able to extract from the food and utilize could be much lower. Vegan and vegetarian dog foods are made entirely of plant-based ingredients, and while any dog is capable of digesting the grains and legumes in these foods, the amount of digestible protein is much lower compared to meat-based protein and could leave your dog with some dietary deficiencies if you aren’t careful.
The Verdict. For most dogs, vegan and vegetarian diets just don’t make sense. They have less protein, are harder to digest, are high in carbs, and are difficult to balance properly… so why would anyone feed them? Aside from the argument of ethics, most of the success stories you hear about these diets have to do with pets that have very severe allergies. For those with extreme protein allergies, moving to a plant-based food may solve the problem. Plant-based proteins are a tolerable source of nutrients, and can certainly do the job if a pet is intolerant to any and all animal-based protein, but this is extremely rare and often simply a misconception. Although some dogs may experience allergy symptoms when fed certain animal-based proteins, this often has to do with how heavily processed meat is when baked in kibble - often, when fed the raw version of the protein, the allergy symptoms disappear! So before you make the switch to a plant-based food, remember to keep in mind that this side of the industry is fairly new, and there are few studies on the long-term effects of vegan/vegetarian diets. Additionally, nutritional deficiencies can take a long time to show up, so even pets who do well on these diets in the short-term can suffer complications in the long-run.
Overall, it’s important to remember that dogs’ digestive systems were built to handle fresh, raw meat and other animal-based proteins (i.e., eggs, goat milk), so most will do better on a meat-based diet. Fruits, veggies, and even healthy grains can certainly add value to your dog’s meals, but for most dogs, they shouldn’t be the only thing in the bowl.