In recent years, there has been a growing interest in feeding pets, especially dogs and cats, diets that align with their ancestral and evolutionary eating habits. The basic premise is that by looking back at what dogs and cats ate before domestication, we can gain insight into what they are best adapted to eat now.
Proponents of evolutionary or ancestral diets for pets argue that many commercial pet foods contain ingredients that dogs and cats did not evolve to eat. This includes high amounts of grains, starches, and carbohydrates. On the other hand, foods like raw meat, bones, and organs make up a large part of ancestral canine and feline diets. By mimicking these ancestral ingredients, advocates claim we can improve digestive health, reduce allergies, and optimize nutrition in our pets.
In this article, we are going to explore the scientific basis behind evolutionary diets for pets. We’ll look at evidence on the ancestral diets of dogs and cats and how food impacts their health today. We’ll also provide a simple recipe for a homemade treat that aligns with evolutionary eating principles.
The Evolutionary Diet of Dogs
To understand what constitutes an appropriate diet for dogs today, we need to start by looking at what dogs ate before domestication. Scientists believe the dog evolved from a now extinct wolf-like ancestor known as Canis lupus harennensis around 15,000 years ago. These proto-dogs were hunter-gatherers who lived and worked closely with human camps.
Like their ancestors, these early dogs were carnivores who consumed a diet rich in animal foods like meat, organs, bones, and fat. Analysis of isotopes in fossil remains suggests animal foods made up 70-90% of proto-dog diets. The remaining 10-30% consisted of edible plant foods and grains gained as scrap foods around human camps.
This carnivorous ancestry remains evident in dogs today. Evolution has shaped dogs to efficiently process and utilize nutrients from animal foods.
For example:
- Dogs have a simple gut designed for digesting meat, not plant material. Their small intestines are only about 1/3 the length of omnivorous humans.
- Dogs have carnivore-specific teeth including sharp front canines and premolars ideal for slashing and crushing meat.
- Dogs lack salivary amylase, an enzyme that initiates carbohydrate digestion.
- Dogs have nutritional requirements and metabolism adapted to animal-based foods. Around 50-70% of dog diets should consist of high-quality animal sources to meet their needs.
This evolutionary evidence suggests commercial dog foods with large amounts of grains and starches do not align with canine anatomy or ancestral diets. A dog’s system is not adapted to make efficient use of these ingredients.
The Evolutionary Diet of Cats
Cats are obligate carnivores, meaning they must eat meat to acquire certain essential nutrients. This evolutionary diet stems from the feline ancestor Felis silvestris lybica, a Middle Eastern wildcat that lived around 10,000 years ago.
Like dogs, analysis of cat remains and fossils shows these wildcats consumed a strictly carnivorous diet consisting mainly of small prey like rodents, lizards, and birds. When cats moved in around early agricultural societies, scraps of meat, fish, and milk from domesticated animals supplemented their hunting.
But domestication over the past 9,500 years has not significantly changed the cat’s status as an obligate carnivore.
Cats today maintain the same evolutionary adaptations that allow them to thrive on a meat-based diet:
- Short, straight gut ideal for digesting animal proteins and fats
- Obligate requirement for certain amino acids (like taurine) only found in animal tissues
- High requirement for dietary protein with an minimum of 26% protein in cat foods
- Carnivore-specific teeth and jaws adapted for shearing, biting flesh
- Cats lack ability to synthesize vitamin A from plant sources
- Low or absent expression levels of genes for carbohydrate digestion
Because of this clear biological dependence on meat, cats have stricter dietary requirements than dogs. Commercial cat foods containing high amounts of grains, carbohydrates, and plant material do not match up with feline evolutionary eating patterns. A cat’s digestive system and metabolism are geared for almost exclusively animal ingredients.
How Ancestral Diets Impact Pet Health
Now that we understand the evolutionary diets of dogs and cats, how does this information translate to health benefits today? Let’s look at some of the key ways an ancestral diet can improve dogs and cats:
Better Digestion
When you feed foods aligned with an animal's evolution, their digestive system functions optimally. Species-inappropriate ingredients like grains and carbs can irritate the stomach, cause inflammation, and lead to diarrhea or vomiting. Ancestral diets avoid these issues.
For example, the high fiber content of plant foods speeds up transit time in the large intestines of dogs and cats. Herbivores like cows have a digestive tract designed to handle this. But in carnivore colons, fiber often fails to ferment and contributes to loose stools. Sticking to evolutionary ingredients tailored to the pet digestive anatomy prevents these issues.
Reduced Allergies
Food allergies and intolerances are on the rise in pets, especially to common proteins like beef, dairy, chicken, and eggs. But proteins and fats from novel or ancestral meat sources like duck, venison or other gamey meats are less likely to trigger allergic reactions. Rotating between proteins with different antigen profiles may help reduce overactivity of the immune system.
Additionally, grain-free ancestral diets alleviate allergy issues associated with ingredients like wheat, corn, and soy. One study found 83% of dogs with grain-allergies saw complete resolution after switching to a grain-free diet.
Optimized Nutrition
As the dominant ingredients in ancestral pet diets, animal foods provide the essential amino acids, fatty acids, vitamins, and minerals dogs and cats need in bioavailable forms. In contrast, excess grains, fiber, and carbs can interfere with nutrient absorption.
For example, cats eating dry foods with higher carbohydrate content show lower blood taurine levels than cats eating high protein, low carb canned formulas. Taurine is an amino acid only found in meat that cats cannot synthesize enough of on their own. Ancestral-based nutrition avoids nutrient deficiencies related to inappropriate ingredients.
Leaner Body Composition
The hunter-gatherer existence of wild dogs and cats required a lean, muscular frame for catching prey and surviving. Today, studies show ancestral ingredient diets help maintain a healthy body composition compared to carb-heavy conventional diets.
In one study, Labrador retrievers eating a high protein, grain-free diet for 6 months showed significant reductions in body fat compared to dogs eating a high starch diet. The ancestral diet dogs lost weight while maintaining lean muscle mass.
Improved Oral Health
Ancestral diets that incorporate raw meaty bones provide abrasive chewing surfaces that break down plaque and tartar as the dog or cat eats. In contrast, highly processed kibbles do little to clean teeth or improve dental hygiene. One study found a raw food diet reduced plaque and calculus buildup in dogs by 35-43% compared to commercial diets.
The evolutionary diets of dogs and cats provide a template for formulating modern day pet foods optimized for health. Focusing on high quality proteins, fats, and minimal digestible carbs provides the most bioavailable nutrition. Let’s now turn to a simple recipe for an evolutionary-based homemade treat.
Recipe: Bacon and Beef Liver Dog Treats
The following homemade treat recipe for dogs focuses on nutrient-dense ancestral diet ingredients:
Ingredients:
- 6 strips uncured bacon, diced
- 1 pound beef liver, cut into bite-size pieces
- 1 large egg
Instructions:
- Preheat the oven to 350°F. Line a baking sheet with parchment paper.
- In a non-stick skillet over medium heat, cook bacon pieces until crispy. Remove with a slotted spoon and drain on a paper towel. Reserve bacon fat.
- Pat liver pieces dry and lightly fry in 2 tbsp reserved bacon fat for 2-3 minutes until cooked through but still moist. Remove from the pan.
- In a food processor, pulse the egg briefly until uniform. Add cooked bacon and liver and pulse until evenly chopped but still chunky.
- Using hands, form heaping tablespoon-sized balls of the liver mixture and place on a prepared baking sheet. Bake for 8-10 minutes until lightly browned.
- Remove from the oven and let treats cool before serving. Refrigerate leftovers for up to 1 week.
This simple treat provides a tasty source of animal protein and fat from bacon and liver that aligns with canine ancestral diets. The bacon fat provides a healthy source of energy while the liver is packed with vitamins, minerals, and other micronutrients. Adjust ingredient amounts based on your dog's size and needs. Pair with a balanced commercial diet or raw food diet.
Conclusion
The evolutionary diets of dogs and cats provide insight into the types of ingredients and proportions we should feed our pets today. Focusing on high quality proteins, fats, and minimal carbohydrates provides the most bioavailable nutrition. Transitioning to an ancestral diet can improve digestion, reduce allergies, optimize nutrients, and maintain healthy body composition in pets.
Simple homemade recipes like liver treats make it easy to supplement commercial diets with evolutionary ingredients. While long-term studies are still needed, the biological evidence supports ancestral-based nutrition as a healthy way to feed our dogs and cats.