Are Dogs Carnivores or Omnivores?
This should be a simple, but it is actually a much debated question in the canine world. While it is universally agreed that cats are carnivores, “experts” differ on whether dogs are carnivores or omnivores.
Although many dogs enjoy eating anything that you give them, this does not necessarily mean that those foods are the best for your dog's health. Dogs are biologically designed to be carnivores, and because of this they require meat in their diet. There are far too little benefits to justify having your dog on a plant-based diet. To have the healthiest and happiest dog, you have to remember that they need to eat like a dog, and what works for you doesn’t necessarily work for them.
Diets of Carnivores vs Omnivores
Carnivorous animals eat, and thrive on a primarily meat diet, whereas omnivorous animals eat, and thrive off a roughly equal mixture of meat and plants. Herbivorous animals eat plants, and insectivorous animals eat predominantly insects.
Biologically, humans are omnivorous, designed to eat both meat, and plant matter. Felines are carnivorous; they’re actually obligate carnivores, which means they do not utilize any plant matter well. Canines are facultative carnivores which is somewhere between an obligate carnivore (only eating meat) and an omnivore (eating both meat and plant matter).
Facultative carnivores like dogs eat a predominantly meat mased diet, and need this to thrive, but can benefit from a small amount of fiber (plant matter in the form of vegetables and some fruits). Healthy vegetables include broccoli, carrots, green beans, pumpkin and celery.
Domestic and wild dogs are part of the Canidae Family, (Order ‘Carnivora’). Other species in this Order, include Grey Wolves (of which our domestic dogs share 99.9% of their DNA), jackals, foxes, wild dogs and dingoes.
The Canine Digestive Tract
Comparing the digestive tract of dogs and other carnivores with that of herbivores, or omnivores, the differences clearly show that dogs are carnivorous. A predominantly meat based diet takes less time to digest, so carnivores have a much shorter digestive tract than animals who eat a large amount of plant matter.
The stomach is an important part of the digestive tract. This is where gastric juices mix and break down food, ready for digestion. The carnivores stomach is always single chambered, taking up around 60-70% of the entire capacity of the digestive system. This allows for consumption of large meals, eaten very quickly.
Studying the intestines of a dog, or any other carnivore, we see they are incredibly short in comparison to that of a species who consumes a lot of plant matter. As there will be little plant matter to digest, and meat is much easier to digest, the intestine doesn’t need to be longer, in order for it to fully absorb the nutrients gained from the diet. Having a short digestive tract, also ensures any bad bacteria consumed is unable to recolonize.
A final part of the digestive tract to look at, is pH – the strength of the stomach acid. The pH of a carnivores stomach is extremely low, making it extremely acidic; close to that of battery acid. Having such an incredibly acidic stomach, means they are able to digest meat very easily, as well as fight off pathogens within the food consumed. Omnivores have less acidic gastric juices, and herbivores have stomach acid so weak, it is almost pH7 (neutral), which teamed with a longer digestive tract, aids the slower digestion of plant matter.
Jaw and Dentition
The size, shape, and dentition (the way the teeth fit together) of a dog’s mouth facilitates their diet.
Carnivore teeth are designed to tear meat, swallow, and be further digested in the stomach. The canine teeth are sharp, pointed, and long, giving the strength necessary to penetrate raw meat. As well as the shape and sharpness, a dogs’ teeth are fitted tightly together, allowing less chewing and the ability to simply swallow for digestion.
Omnivores on the other hand have long, large and flat molars designed to grinding of plant matter. Their jaws allow for more side-to-side, backward and forward movement also for breaking down plant matter more easily.
Canines have a large mouth opening. This enables carnivores to catch, kill and rip their prey apart. Omnivores don’t need to do this, so have a much smaller oral opening.
A carnivores’ jaw is hinged and very stable whereas the jaw joint in ominivores is more complex but slightly less stable.
Herbivores have teeth that are highly specialized for eating plants. Because plant matter is often difficult to break down, the molars of herbivores are wider and flatter, designed to grind food, and aid in digestion.
In carnivores, the jaw has extremely limited movement, just up and down. This allows for the jaw to act almost like a pair of scissors, chopping the meat consumed in to smaller pieces in order to make them easier to swallow.
Both carnivores and omnivores have Insciors and molars. The canines of a carnivore are very long, and pointed, equipping the animal with it’s own daggers, to rip and tear the meat. Omnivores have canines which are a similar length to the incisors, only very slightly pointed.
Finally, the molars. Those of carnivores are slightly pointed, but very flat compared with other teeth in the mouth. These help grind down bone, fur, and a little fibrous plant matter. Omnivorous molars are very much flat, and not pointed, to create a larger surface area which is able to cope with grinding down more plant material.
Enzymes
The type and amount of enzymes naturally occurring in carnivores are very different to those of omnivores.
When looking at plant based sources of omega, carnivores really struggle with the conversion of plant based sources of ALA, to EPA and DHA, due to the lack of D5 desaturase enzyme. Cats are physically unable to convert plant based ALA into EPA and DHA, as they completely lack the enzymes required for the conversion. Dogs are only able to convert around 5 to 15% of plant based ALA sources due to not naturally producing the amount of D5 desaturase enzyme required for the process. This is why flax based omega products are not the best option for our carnivorous canines, as they are notoriously difficult for dog to utilise efficiently.
Amylase, the enzyme responsible for the breaking down of carbohydrates, is the other main enzyme which proves our dogs are facultative carnivores. The gene responsible for production of amylase, is called AMYB2. Recent studies show that unlike wild carnivorous mammals, who only have two copies of the gene, domesticated dogs have between 3 and 32 copies – this very much depends on the breed of dog. While this gene is more present in domestic dogs, than in their wild cousins, there is not enough to enable a dog to digest a high carbohydrate diet, but does allow them to benefit from a little plant matter, which brings about the benefits of polyphenols, antioxidants and phytonutrients found in some plants. This is the main difference between a facultative carnivore, and an omnivore; who would have far more copies of the gene, and therefore the ability to digest higher amounts of carbohydrates.
Omnivores also have the amylase enzyme in their saliva, which helps start the process of digestion during mastication. Dogs however, do not need this, as carnivores eat quickly, so digestion occurs in the gut.
Is the Industry Biased?
Unfortunately it would appear so. Many within the pet health industry market their low quality, non-biologically appropriate, and generally ultra processed dog feeds, as the “best” for your dog. These large corporations (owned by larger parent companies) are unquestionably profitable. This in turn allows them to conduct their own studies on certain aspects of pet care, contrary to the hundreds, if not thousands of studies already available to them in current scientific journals. As a company, understandably they need to be profitable – and consumers like to think they are buying a food backed by studies. But when you are looking at food trials and studies, it is important to review the independent studies also, not just the ones carried out by the companies themselves, or by those with links to the companies.
As an example, a paper written in 2013, and funded by a large pet food company, stated that dogs were omnivores because they can eat plant matter. However, they failed to explain that that while dogs can survive on plant-based diets, this does not equate to thriving.
It is important to understand that “food trails” are comprised of a group of dogs fed a specific diet for a set period of time, for example 30 days. The participants are then examined at the end of the trial to ensure no major changes have taken place metabolically or physically. All this tells us is that that group of dogs survived on that food for the set period of time. Congratulations, the dogs didn’t die eating your food for 30 days. This is not an indicator of whether this food improves their health or longevity. I can’t tell you how many times I have asked a vet why their recommended brand is the best. Honestly, they are always surprised by the question and the usual response is that the particular brand in question “is backed by food trials”. That’s a lot like saying Cheerios is the best cereal for people because General Mills can afford to study a group of people who eat only Cheerios for 30 days.
A Vegan Lifestyle
Many people have made the decision to eat only plant matter for themselves which is great. But try not to let your own morals and emotions influence what is right for your pet. Canines need meat to thrive. The vegan formulas being touted in dog food are usually over processed, not biologically appropriate, high in synthetic nutrients in order to make them a “complete and balanced” meal and unfortunately extremely high in carbohydrates. Again, while dogs can and will eat plant matter, it does not mean they would choose this over quality meat based protein and it is not what they were designed to eat.
Lifespan
Some other food for thought. The average life expectancy of dogs, since higher plant based foods have been brought to market, has reduced from 17 years to 10.5 years! Overall, the lifespan of our pets has declined and cancer rates have increased in the last decades rather than going the other way. Why is that? Highly processed food and an increase in vaccines, flea, tick and heartworm chemicals regularly applied or ingested and more and more toxins in and outside our home from pest control, lawn fertilizer, cleaning supplies, paint etc.
So What is Recommended For Our Canine Companions?
Dogs are scavenging carnivores rather than an omnivore, due to their physiological make-up. They are not meant to eat the same overly processed dry kibble for their entire lives.
Since they have zero requirement for carbohydrates, they should be fed in small amounts if at all.
We recommend feeding a fresh, balanced diet with predominantly meat sources to benefit their health, longevity and mental wellbeing.
What to Look For
Quality protein from named animal sources (salmon, duck, beef) versus unspecified animal sources (animal, fish, poultry) for the top two or three ingredients. Unnamed protein sources and “meal” are typically low quality and/or from rendered waste.
Minimally used plant proteins (ex: peas, lentils, chickpeas). These are inexpensive, often high GMO options used to replace quality protein.
Lower carbohydrates – ideally 29% or less. Dogs have no nutritional requirement for carbs but they may be added for energy, texture and taste as well as to assist in the extrusion process for dry foods. Foods high in carbs can raise insulin and cause obesity.
Minimal synthetic vitamins. Being “fortified with vitamins” indicates poor protein source or vitamins and minerals that did not survive the high heat extrusion process and needed to be artificially added back in.
No food coloring or dyes or synthetic preservatives.
Read more about the foods we recommend under the Info page of our website.
