By Carrie Hyde, The Spaw Pet Life Coach | November 10, 2021
The number of Americans following a vegetarian or vegan diet has risen sharply in the past decade. This trend comes as more and more consumers become aware of the vast impacts their diet has on not only their own health but that of animals and the planet.
If you happen to be a dog owner who has embraced a plant-based diet to help reduce animal suffering and your climate impact, then you may also be considering ways to change your pet’s diet to do the same.
But is it possible for dogs to eat a plant-based diet? And, more importantly, is it healthy?
In this article, we’ll look at the dietary needs of domestic canines and how this affects their ability to eat a vegetarian or vegan diet. We’ll also look at some ways you can modify your dog’s diet to help reduce their impact on the planet and on livestock suffering, without sacrificing their health.
Are Dogs Carnivores?
Before we get into whether or not dogs are carnivores, it is important to understand what that term really means.
A carnivore is any animal that eats mostly meat. This is slightly different from an “obligate carnivore,” which is an animal that is physically incapable of getting enough nutrients from plants to survive.
Cats are obligate carnivores and must eat some amount of animal meat to survive. Dogs are carnivores but are not obligate carnivores, which means they have evolved to eat a diet of meat but can survive without it.
Now before you run off to fill your dog’s bowl with salad, it is important to note that just because an animal can survive on a certain diet doesn’t mean it is in their best interest to be on that diet. A human, for instance, could survive on a diet of hamburgers and chocolate cake, but that certainly doesn’t mean they’d be healthy if that’s all they ate.
To understand what a dog needs to eat not just to survive, but to be healthy, we need to look at how they evolved.
Dogs’ Wild Ancestors
Domestic dogs descended from the same ancient wolf species as modern-day gray wolves. By looking at the diet of gray wolves and other wild canids, we can get a good picture of what dogs evolved to eat.
Gray wolves, for instance, exist on a diet that is about 54% fat, 45% protein, and 1% carbohydrates(1). All that fat and protein comes from meat. What little carbohydrates they eat come from consuming the stomach contents of their prey, feces, berries, grass, and other random plant material they scavenge.
The teeth, stomach, and digestive tract of wolves and domestic dogs are very similar. This tells us that dogs, despite looking very different on the outside, are still built to maximize nutrient absorption from meat on the inside.
The Modern Dog
Dogs are estimated to have been domesticated sometime in the last 40,000 years. In evolutionary terms, this is a very short period, which explains why we have not seen much structural change in the canine digestive tract despite modern dogs eating nothing close to their wild relatives’ diet.
But that doesn’t mean that some changes haven’t occurred. For instance, domestic dogs have a different gut microbiome than wolves which allows them to more effectively break down starches(2). The production of amylase, an enzyme found in saliva that helps break down starch, is also much higher in domestic dogs, especially in breeds that evolved alongside agrarian societies(3). Small changes like these were necessary for canines to go from hunting and eating prey animals to scavenging off the scraps left by humans. They have become even more important in today’s dogs who are subjected to commercial diets, most of which contain far more carbohydrates than protein and fat.
The Problem with Dogs Eating Plants
While dogs may have some special adaptations to help them eat plants, that doesn’t necessarily mean this type of diet is what’s best for them.
Domestic dogs have an average lifespan of around 12 years while feral dogs that survive by scavenging on food thrown out by humans rarely live long enough to see the age of five. Captive wolves fed a natural raw meat diet, on the other hand, live 17 years on average.
This is one of the clearest representations of how a diet can sustain life without maximizing an animal’s health. A diet that is mostly plant-based ingredients can keep a dog alive long enough for them to reach adulthood, but it won’t offer enough the right kind of nutrients to optimize their health.
Access to Micronutrients
It is no secret that the canine digestive tract struggles to digest plant cellulose. If you’ve ever watched your dog gorge on grass and then pass it later, you know this is true. But it’s not just fibrous grass that dogs can’t break down.
Any nutrients locked inside intact pieces of plant material are going to be inaccessible to the canine system. That means, unless the food is pulverized and processed, those nutrients may as well not exist in the diet at all.
But processing food to destroy cellulose comes with its own drawbacks. Most notably, heat processing, commonly used in commercial dog food production, destroys micronutrients. This is true whether the processed food in question is high in meat or plant ingredients. In either case, those missing micronutrients have to be replaced with synthetic nutrients, which are added after the processing step. Unfortunately, synthetic nutrients are often just as hard for the body to absorb and don’t come naturally packaged with the enzymes and companion nutrients the body needs to make use of them.
Different Macronutrients
Macronutrients, which are protein, fat, and carbohydrate, are the three types of calories found in food. All three of these macronutrients can be found in plant and animal ingredients but in vastly different ratios.
Meat, bone, and organ meat are high in protein and fat and contain only trace amounts of carbs. Fruits and vegetables, on the other hand, are very high in carbohydrates, contain some protein, and trace amounts of fats (with a few exceptions).
When replicating the macronutrient profile of the canine diet using plants, you cannot use whole-food ingredients. Instead, you must use processed ingredients like vegetable oil and pea protein to maximize fat and protein content without adding too much starch.
Not only does this present the same problem of overprocessing we discussed above, but it also ignores the fact that plant-based fat and protein are very different from what you find in animal ingredients.
The type of iron, the ratio of fatty acids, and the amino acid profile of plant ingredients are vastly different from what the canine body evolved to use. The best example of how this can cause problems has to do with the amino acid taurine. Canine diets with too many plant-based ingredients interfere with the natural absorption of methionine and the formation of cysteine, two key amino acids in the formation of taurine.
When dogs cannot make enough taurine, it causes a host of serious problems in their body, most notably, dilated cardiomyopathy. This often fatal condition causes the muscles of the heart to thin and the chambers to become enlarged. This is just one example of how a vegan diet, even one that has been created to mimic the nutrient profile of a meat-based diet, can cause dogs serious harm.
How to Feed Your Dog Humanely and Sustainably
As omnivores, humans have evolved to eat a highly variable diet. Our bodies make all the enzymes we need and have the long intestines necessary to digest plant cellulose and utilize plant-based nutrients. This gives us the option to eat a vegan diet as a means to reduce animal suffering and lower our impact on climate change without sacrificing our health.
Our dogs, unfortunately, do not have these same abilities. But that doesn’t mean it isn’t possible to lower your pet’s impact on the environment while still maintaining their health. If you are interested in helping your dog do their part for animals and the planet, here are a few steps you can take to adjust their diet without impacting their health and longevity.
Choose Better Meats
What defines a “better meat” depends on whether you are speaking in terms of what’s humane or what’s better for the planet.
Humanely speaking, free-range, organic meat is better than the alternative. These animals are raised in open, more natural environments and are guaranteed the space and means to perform natural behaviors. You can take this a step further by only feeding your pet meat, eggs, and dairy that come with the “Certified Humane” seal.
Unfortunately, these kinds of products are not the best option for reducing your dog’s climate impact. Because humanely raised, organic livestock takes more time to mature, these animals use a lot more resources than their factory-farmed counterparts. If you want to reduce animal suffering and your climate impact, choose meat types that are highly nutrient and calorie-dense. These include things like small oily fish, organ meat, and rendered meat meals. Not only will you have to use less meat overall when feeding these, but oftentimes these animal parts are extras from the butchering process, meaning no additional animals are slaughtered to produce them.
Another option would be to contact local hunters’ clubs to see if you can use extra parts from the game they take. Just use caution when feeding raw, wild-harvested game meat. Rabbits and some other game animals can carry diseases that are transmittable to dogs. In these situations, cooking the meat would be the safer choice.
Swap Some Meat for Vegetarian Alternatives
The same digestive processes that make dogs good at digesting meat and bone also make them pretty good at utilizing other animal products, such as eggs, yogurt, and dairy. You can reduce your dog’s dependence on butchered meat by replacing some of the protein and fat in their diet with these vegetarian animal products. Cooked eggs are always a great option and can often be sourced from local, small farms. Dogs do not have the same ability to digest lactose as humans, so dairy use should be restricted to easily digestible forms like yogurt and raw goat’s milk.
Supplement Easily Digestible Plant Options
You can also reduce your dog’s meat needs by replacing some of their food with highly digestible, high-nutrient plant foods.
Mushrooms, which are part of the fungus family, have more protein than plants and do not typically contain cellulose. These days, it is fairly easy to find powdered mushroom blends that provide tons of bioavailable nutrition to humans and canines alike.
For dogs that aren’t sensitive or allergic to soy, tofu is another good option for providing extra protein in place of meat. Tofu is made from soy milk and doesn’t contain the high cellulose levels found in raw soy. It is easy for dogs to digest and provides plenty of protein and amino acids. Ground seeds, such as chia and flax, are a great option for adding fat to your dog’s diet. Seeds do contain a fair amount of cellulose, so they need to be finely ground before feeding. Other nutrient-dense superfoods such as berries, dark leafy greens, and sweet potatoes can also be fed in small quantities so long as they are blended or dried and ground first.
Feed Your Dog Responsibly
Can your dog eat a plant-based diet? If you value your dog’s health and wellness, the answer is no. Dogs are carnivores with digestive systems optimized to absorb nutrients from high-fat, high-protein meat diets. They are unable to digest cellulose and struggle to maintain optimal health when fed strictly plant-based ingredients.
But that doesn’t mean your dog can’t do their part to help reduce their climate impact and reduce livestock suffering. By choosing responsibly raised nutrient and calorie-dense meats, replacing some protein and fat with vegetarian animal products, and replacing some food volume with highly digestible plant-based superfoods, you can reduce how much meat your carnivore consumes without putting their health at risk.
By Carrie Hyde, The Spaw Pet Life Coach | November 10, 2021
Written for The Spaw by Sara Seitz, Professional Freelance Writer and Novelist with Pen and Post
Carrie Hyde is the founder, owner, and Pet Life Coach of The Spaw in Tustin, CA. Carrie’s extensive experience and understanding of pet nutrition and coaching enabled her to create The Spawdcast, a podcast dedicated to educating pet parents and pet industry professionals on ALL the options available to their pets. Her mission is to open pet-owner’s eyes to the questions they may not even know to ask, to shine a light on the many myths that have been part of pet care for decades, and to offer whole solutions for their pets. Carrie Hyde is a certified pet nutritionist with the goal of helping pet parents & pet professionals with a new understanding of how to care for pets in a “whole and natural” way.
