Canine Cuisine: "Can My Dog Do Okay on Vegan 'People Food'?"
Yes, he can—and many experts agree.
Posted Apr 22, 2019
I receive numerous emails from people concerning meal plans for their canine companions. They often ask if there are any general "rules of thumb": Do dogs really need to be fed as if they're wolves? What about so-called "people food"? How about vegetarian or vegan diets? A few days ago, I received an email from Dottie asking, "Can my dog do okay on vegan 'people food'?" Dottie's dog is named Marcel, and she told me that while he's "doing great on a healthy and balanced diet of vegan people food, and her vet agrees," some people criticize her for not paying attention to the fact that Marcel is really a carnivore who has descended from wolves and needs meat. In fact, dogs are more omnivores than carnivores, according to a veterinarian and nutritionist.
I decided to write this essay because Dottie's question contains two of the most common questions that come my way—namely, can dogs thrive on vegan diets or other meal plans that contain a lot of "people food." In a previous essay titled "Should I Really Be Feeding 'The Wolf' in My Dog?" I answered a woman's question by writing, "When it comes to diet, treating dogs like wolves doesn’t make biological or nutritional sense." The woman who sent it was confused because of all of the "glitzy advertisements and hype" about the "best" meal plan for dogs. I fully understood her dilemma, so I began my answer to her simply by noting that dogs are not wolves and I was not a fan of feeding "the wolf in a dog." While it's true that a domesticated wolf (but not a socialized wolf) is a dog, there are many differences between wolves and dogs including their meal plans and dietary needs.
I also wrote about the large differences in activity levels between wolves and dogs and that many veterinarians are concerned that there are too many obese individuals among our canine companions. Feeding dogs as if they're wolves could be part of the problem. In addition to having radically different activity levels, dogs and wolves may no longer have identical nutritional needs. For example, researchers recently uncovered an interesting genetic difference between dogs and wolves, namely, that dogs appear to have a greater ability to digest starches. The wolf genome has only two copies of the gene alpha-amylase 2B (AMY2B), which helps with the processing of starch in the pancreas, while dogs have somewhere between four and thirty copies of this gene. (See "Diet adaptation in dog reflects spread of prehistoric agriculture.")
While advertisements for dog food may tout something along the lines of “Feed the wolf in your dog” or “Dogs evolved, but their instincts remain,” these sorts of comparisons can be fraught with error when it comes to actual feeding advice.
What about vegan diets and so-called "people food?"
"Fruits and veggies and grains do not have high enough amounts of cellulose to cause issues with digestion for dogs." (Dr. Cailin Heinze)
Many people get pretty "hot under the collar" when they discuss whether or not dogs can do well on homemade or commercial vegan diets, and opinions range all over the place. I was surprised when I saw a recent essay called "ONE IN THREE PET-OWNERS KEEN TO FEED THEIR ANIMALS A VEGAN DIET" in which I read, "A survey of more than 3,670 dog and cat owners from around the world found that 35 percent are interested in putting their pets on a vegan diet while 27 percent of respondents who follow a vegan diet themselves have already done so." The lead author of the study upon which this essay was based, Dr. Sarah Dodd of the veterinary college at the University of Guelph in Canada, "said she was surprised at how many pet-owners were already feeding their animals exclusively vegan food."
When I decided to go vegetarian and then vegan and choose to do the same for some of my canine companions, we all did very well. I paid very close attention to all of our meal plans, and they and other dogs who I knew were also being fed vegan diets, did as well as their omnivorous friends. When I've asked veterinarians from time to time about their impressions about the health of vegan dogs, they agreed that they did as well as others who enjoyed mixed meal plans. A few of my dogs loved bagels and peanut butter, rice and bean burritos, and various fruits and vegetables. Of course, I never fed them chocolate or other foods to which they might have negatively responded (onions, garlic, avocados, nutmeg, grapes and raisins, macadamia nuts, caffeine, alcohol, marijuana, and xylitol, a sugar substitute that can be found in some sugar-free foods and gums). They were incredibly active, ran off-leash much of the time, never suffered from obesity, and lived long and healthy lives.
Concerning "people food," dog advice columns often decry giving dogs people food, but there is no scientific evidence that the foods we eat are necessarily bad for dogs—or at least, no worse for them than they sometimes are for us. Indeed, this distinction between people food and dog food is more of a marketing gimmick than anything else. Dogs coevolved with humans in part by eating our leftovers and throwaways. Claims that foods such as bread and pasta are bad for dogs don’t have any scientific backing. Setting aside food that is unhealthy for anyone or poisonous, most of the foods we eat seem acceptable for dogs to eat. One of my canine companions, Jethro, loved pasta and, as I wrote above, dogs have somewhere between four and thirty copies of the gene alpha-amylase 2B (AMY2B), which helps with the processing of starch in the pancreas. And, Tufts University veterinarian and nutritionist Dr. Cailin Heinze notes, "Most dogs’ pancreases work very well at this task and dogs do a very good job breaking down starch from plants. The digestibility of most plants that are a common part of human diets is quite high in dogs, not all that different from what it is in people. There is no evidence that feeding a higher carbohydrate diet damages the pancreas in any way." Dr. Heinze goes on to write, "Fruits and veggies and grains do not have high enough amounts of cellulose to cause issues with digestion for dogs."
Pay careful attention to individual differences and seek professional advice when necessary
Dogs show remarkable variability in their tastes for different foods. For example, my colleague Jessica Pierce's two dogs, Bella and Maya, are nothing alike. Bella has a wide palate and will eat carrots, peas, apples, raspberries, and nearly every other food offered to her. Maya dislikes fruits and vegetables and will carefully pick them out of Jessica’s offerings, even if they’re hidden under thick gravy. Jethro was the consummate omnivore, refusing just about nothing: He ate everything he was offered or that he discovered on the floor, on a counter, or outdoors while on the prowl. One of his nicknames was Leadbelly. On the other hand, Inuk was a disturbingly picky eater who would stick his nose up even when offered a patty of wet dog food laced with ketchup—something Jethro would instantaneously inhale without a snort.
Variety is the spice of life. Indeed, dogs may enjoy, as we do, experiencing a variety of taste sensations. Who wants to eat the same stuff every day? That’s boring. Similar to omnivorous dogs, vegan dogs need variety in their diets, and there are numerous options.
There's still much we don’t know about the ideal canine diet, despite the many claims we hear from dog food manufacturers, veterinarians, and self-proclaimed dog experts. (See Unleashing Your Dog: A Field Guide to Giving Your Canine Companion the Best Life Possible for more discussion of dog meal plans.) Very few of these claims are backed by scientific research and actual evidence, so it’s best to treat this advice as mostly opinion and anecdote, some of which is clearly intended to sell this or that brand of dog food. Dogs' mouths aren't trash cans. And, what’s most essential, is that you pay very close attention to what your dog likes and dislikes and feed their fancy. Individuals' tastes matter.
So, can Dottie's dog, Marcel, do okay on vegan people food? Yes, he can, and many experts agree. So too can other dogs as long as their human companions pay close attention to their health and seek professional guidance when needed, things they should do regardless of their dog's diet. Stay tuned for more discussion of canine meal plans and numerous ways to make them more humane and at the same time as nutritious as they can be.
Note: This also is of interest: VEGAN DOG TREATS RECEIVE $550,000 ON ‘SHARK TANK!’
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Comment: A word of caution from Michael W. Fox, BVetMed, PhD, DSc, MRCVS:
Many dogs, especially German shepherds, get pancreatic insufficiency--run out of starch-digesting enzymes--when on a high grain/starch diet. Some other breeds develop irritable and inflammatory bowel diseases and colitis--partially the gluten problem--and associated allergies from the secondary leaky gut syndrome.
Dysbiosis (an unhealthy population of gut bacteria) associated with biologically inappropriate diets can lead to other health problems that are rectified by dietary corrections and supplements.
Corn and wheat can cause seizures in dogs and soy causes bloating and indigestion, indicative of food intolerance. A high fiber diet can lead to constant hunger and malnutrition while a high carbohydrate diet can lead to obesity, diabetes, arthritis and other health problems.
Alternative dietary inclusions such as potato, pea flour and lentils (pulses) have been recently linked with dilated cardiomyopathy in dogs. High levels of lectins in these ingredients may interfere with uptake of taurine which is an added supplement in most manufactured dog and cat foods.
Omega 3 and DHA (docosahexaenoic) and EPA ( eicosapentaenoic) fatty acid deficiencies and high levels of Omega 6 from corn in vegan and vegetarian diets for dogs (and people) are also a major concern. Deficiencies can underlie serious skin disorders, inflammatory conditions and are essential for the neurological and visual development of puppies. Pregnant bitches should therefore not be given biologically inappropriate and deficient diets. These fatty acids may also slow down cognitive decline in aging animals and certainly help sustain cardiac health.
Dogs and cats are often allergic to eggs and dairy products or have varying degrees of dietary intolerance.
My ultimate concern is that dogs (and cats) on biologically inappropriate diets may present clinical problems that some veterinarians will address primarily and possibly exclusively, believing that the animals are being fed an adequate diet. Treating the symptoms and consequences of improper nutrition rather than addressing the root cause has happened in many instances especially with dogs and cats being fed manufactured pet foods sold by the veterinarians who believe that the foods are no problem, along with profitable prescription diets.
These concerns and others about many conventional manufactured pet foods with “junk” and hazardous plant and animal ingredients condemned for human consumption are documented in the book that I co-authored with two other veterinarians, Not Fit for a Dog: The Truth About Manufactured Cat and Dog Foods. For more details and home-prepared recipes for dogs and cats, visit www.drfoxonehealth.com.
M. Arendt et al. Diet adaptation in dog reflects spread of prehistoric agriculture. Heredity 117: 301-306, 2016.
Cailen R. Heinze. Vegan Dogs – A healthy lifestyle or going against nature? Petfoodology, the scientific study of pet nutrition by veterinary nutrition specialists and experts. Cummings Veterinary Medical Center, Tufts University, July 21, 2016.