- Not a substitute for professional veterinary help.
Many people assume dogs are carnivores, or meat eaters, due to their origins as meat-loving wolves. Yet while dogs may have eaten mostly meat thousands of years ago, their palates have evolved over time.
Believe it or not, today’s dogs are omnivores, which means they can eat both meat and plants.
We interviewed several pet experts to learn where the idea of dogs as carnivores comes from and what a dog’s anatomy says about their nutritional needs. Read on to get the details, plus learn why the right diet plays such an important role in your dog’s health.
Where Does The Idea Of Dogs As Carnivores Come From?
Dr. Emily Luisana, DVM, DACVIM, a veterinarian and clinical nutritionist at Friendship Hospital for Animals, says there’s a lot of confusion about what the words “carnivore,” “obligate carnivore,“ and “omnivore” mean.
Obligate carnivores, or “true” carnivores, are animals whose diets rely solely on nutrients found in meat.
Other types of diets include:
- Facultative carnivore: These animals sometimes eat meat, just not as a primary food source. They also eat plants.
- Omnivore: These animals eat both meat and plants as main food sources.
- Herbivore: These animals eat only plants.
“Being an obligate carnivore would mean that dogs must have meat and can’t process plants, which isn’t true. This line of thinking may lead dog owners to assume an all-meat diet is necessary or healthy,” she explains. In reality, dogs are omnivores and can eat both meat and plants.”
Cats, on the other hand—er, paw—are obligate carnivores. They require a high-protein diet that includes taurine, an essential amino acid only found in meat, and their systems are unable to adapt to changes in the composition of their diet.
The idea of dogs as carnivores comes from dogs’ history as domesticated wolves, who are also obligate carnivores. However, dogs genetically diverged from wolves 20,000–40,000 years ago. What’s more, dogs evolved away from a carnivore diet after they learned to include waste from human settlements in their diets.
In short, the (pretty ancient) history of canine ancestry shouldn’t be the foundation for their modern-day diet and training.
It’s more helpful to think of dogs as omnivores, or as carnivores that require additional nutrient groups on top of protein for a full nutritional profile. Dogs may not always seek out high-protein foods, either. In one 2018 study, some dogs repeatedly chose food that tasted good to them but had less protein than other foods offered.
Nutritional Needs According To A Dog’s Anatomy
Dogs’ bodies have adapted to an omnivorous diet over tens of thousands of years. Your dog’s teeth, saliva, stomach, guts, and even poop clearly support this fact!
Dogs have sharp canines to tear their food, as well as molars to help them crush and grind plant material.
Unlike carnivores and herbivores who tend to eat foods with minimal starch, dogs can digest nearly all carbohydrates they eat.
A dog’s small intestine is similar to those of other omnivorous animals: It takes up about 23% of the total gastrointestinal volume. The small intestines of cats and other obligate carnivores are much smaller.
Sense of taste
Dogs may prefer a certain food because of its appearance, odor, flavor, and texture. Additionally, the most common units of a dog’s taste buds responded to amino acids that humans have described as “sweetish.” This is worth noting, as cats and other obligate carnivores don’t have a sweet tooth.
A recent study on fossilized dog feces found that ancient dogs’ gut microbiome composition showed evidence of an omnivorous diet that included starchy foods.
Modern-day dogs should have a “Goldilocks stool,“ according to Dr. Luisana: “Not too firm, not too soft, and easily picked up.
A few factors that determine stool quality, she says, include:
- Gastrointestinal (GI) bacteria
- Time in the digestive system
- The presence of inflammation
If your dog’s poop has an unusual consistency or color, Dr. Luisana says high-fiber vegetables and grains may help regulate stool quality and provide fuel for healthy GI flora, or microorganisms in the gut.
Can dogs eat vegan?
A carefully designed vegan or vegetarian diet can work for your dog. In fact, some canine nutritionists may prescribe this type of diet to treat various health concerns, like pancreatitis or food allergies.
That said, it’s generally not advised to feed your dog a commercial vegan diet, as these foods may not meet all of your dog’s dietary needs. While a vegan diet can have benefits in some cases, a diet that isn’t nutritionally complete may put your dog at risk of malnutrition.
Instead, work with your vet, who can provide a carefully balanced eating plan for your dog. They may also recommend nutritional supplements to ensure your dog gets all the nutrients they need.
What Nutrients Do Dogs Actually Need?
Dr. Luisana says dogs have many essential nutrients, including essential amino acids, essential fatty acids, vitamins, and minerals. When she examines a diet, she looks at over 40 different parameters.
“While protein is a wonderful source of some of these nutrients, a meat-only diet will result in deficiencies that can eventually be lethal,” she says. “In addition, there are nutrients that are important but not considered essential, such as phytonutrients and certain antioxidants. Vegetables and fruits can be a wonderful source of these nutrients.”
Alex Schechter, DVM, a veterinarian at Burrwood Veterinary, says carbohydrates can be a valuable source of energy, although dogs don’t necessarily need them. According to Schechter, dogs should also eat fiber to support bowel health and promote healthy digestion.
Daily nutrition for dogs
We gathered insight from our experts on essential micronutrients, nutrient quantity, and food sources for a healthy dog diet.
|Nutrient||Daily amount (Dry matter basis)||Ideal food sources|
|Protein||18%–22% or 5-10 grams per 100 calories||Meat, fish, eggs, soy|
|Fats||5%–8% or 2–6 grams per 100 calories||Chicken fat, fish and flaxseed oils, coconut oil, beef fat|
|Carbohydrates||30%–60% or 8–17 grams per 100 calories||Vegetables, fruits, sweet potatoes, millet|
|Fiber||2%–4% or 0.5–4 grams per 100 calories||Brown rice, whole grain oats, beet pulp, carrots|
Dr. Luisana says it’s important to remember that dogs are all individuals, which is exactly how she treats her patients.
“Each one has different nutritional needs and considerations. For example, some may benefit from a high-protein diet, while others may benefit from a low-protein diet.”
She adds that nutritional requirements may vary by dog breed and size, along with underlying health concerns and dog-to-dog differences.
Dr. Ivana Crnec, DVM, a veterinarian at Veterinarians.org, agrees, noting that nutritional requirements can also vary depending on a dog’s lifestyle. For example, a mostly sedentary dog will have different nutritional needs from a dog who spends a lot of time running or working outdoors.
Puppies and dogs that are very active may need a diet higher in protein and fat, while older dogs may benefit from a diet lower in fat and calories, Schechter adds.
How To Choose The Best Diet For Your Dog
When it comes to deciding on your dog’s diet, it’s important to consider essential nutritional guidelines for dogs. For example, your dog’s food should contain at least 18% protein and at least 5% fat on a dry matter basis.
If you’re picking a new dog food, talking to your vet first is always a good idea. They can offer more guidance on the right diet, based on your dog’s individual needs.
Crnec also emphasizes the importance of choosing a dog food that’s nutritionally complete and balanced for your dog’s specific life stage.
The best way of knowing the food is nutritionally complete and balanced, she explains, is by checking if there’s an Association of American Feed Control Officials (AAFCO) statement on the packaging. This non-profit organization that sets the nutritional standards for complete and balanced pet foods. So, an AAFCO statement means the food meets or exceeds their nutrient standards or has completed a feeding trial that aligns with AAFCO guidelines.
Dog food should also come from a trustworthy manufacturer, Crnec says. She recommends reading reviews from customers and checking if the food was used in feeding trials before being sold. Feeding trials aren’t mandatory, but they can help validate whether a pet food brand is actually complete and balanced.
She also suggests considering other factors, like market availability, ease of use, price, and of course, whether your dog will like it. “Palatability is a major factor—the best dog food will be useless if the pet dislikes its taste and refuses to eat it,” Crnec says.
Tips for choosing a food
As a general rule, Crnec also recommends pet parents avoid dog foods that:
- Aren’t nutritionally complete and balanced for your dog’s life stage
- Don’t have a high-quality animal-sourced protein as the first ingredient
- Contain dangerous preservatives, like BHA, BTA, ethoxyquin, or propylene glycol
- Contain artificial colors, flavors, and other additives
- List generic ingredients without specific descriptions, like “animal fat” instead of “beef fat” or “chicken fat”
- Contain sugar, which is used as a flavor enhancer
- Contain carrageenan, which is used as a thickening agent and texture enhancer
- Include hazardous and poorly studied ingredients, like onion or garlic extracts
There’s a diet for nearly all dog needs, including weight loss, low protein, and high fiber diets. (There’s even a green bean diet.) Even if your dog is a picky eater, needs to put on more weight, or get more nutrients from fresh ingredients, your vet can help you find the right food.
Some people even try a raw diet, or a diet made up of raw meats, eggs, fruits, and vegetables. Just keep in mind it’s essential to work with a vet when feeding your dog a raw diet—or if you have any concerns about your dog’s dietary needs.
Ultimately, what matters is that your dog is happy, healthy, and eating the right foods for them!