By Dr. Karen Shaw Becker
As those of you who visit here regularly know, I have a lot to say about the processed pet food industry, and most of it isn't good. Recently I came across an industry journal article that posed the question, "How important is biologically appropriate pet food?"1
You see, this is yet another example of why I'm perpetually annoyed with Big Pet Food. How could feeding animals the nutrition their biology is designed for not be important? How is that even a question in this day and age? And of course, since this is an industry journal, the focus of the articles is most often on what types of pet food are selling well, and this one is no different. From the article:
"Growth of sales of biologically appropriate pet foods has been fueled by anecdotal reports of health benefits and marketing focusing on the domestication of cats and dogs from their wild ancestors."
In case you aren't aware, the big players in the pet food industry, as well as most conventional vets and board-certified veterinary nutritionists, shun anecdotal reports in favor of peer-reviewed scientific studies. That's all too convenient when you understand the vast majority of pet food research is funded by — you guessed it — big players in the pet food industry.
And guess who conducts most of the nutrition training in veterinary schools. Yep, big pet food. The "anecdotal reports of health benefits" the industry is so quick to disregard are typically from integrative and holistic veterinarians and pet parents who've switched a dog or cat from processed food to a fresh food diet.
Most of these dietary changes are initiated to address a health problem the pet is dealing with, and in almost every case, the animal's health improves dramatically even in cases where the new biologically appropriate diet doesn't directly resolve the disease.
What Part of 'Dogs and Cats Have No Biological Requirement for Carbs' Does Big Pet Food Not Understand?
According to Emma Bermingham, Ph.D., a senior research scientist at AgResearch in New Zealand, as quoted in the journal article:
"The fact that neither the Association of American Feed Control Officials (AAFCO) nor the European Pet Food Industry Federation (FEDIAF) stipulate a requirement for carbohydrates may also have had an impact on the growth of high-protein high-fat diets."2
This is actually a great point and one that is ignored across the board by processed pet food manufacturers. There's a very good reason neither AAFCO nor the FEDIAF has set a minimum requirement for carbohydrates in commercial dog and cat food. It's because dogs and cats have no nutritional requirement for carbohydrates.
Since most processed pet foods are very carb-heavy, it's no wonder the industry is seeing growth in high-protein, high-fat, biologically appropriate diets for cats and dogs. Fortunately, more and more pet parents are seeing what the industry and sadly, the conventional veterinary community refuse to see.
Biologically Appropriate Nutrition Is the First Building Block of Good Health
Plain old common sense and frustration with conventional veterinary medicine is leading a growing number of people with sick pets to see if a transition to a more biologically appropriate diet might improve their animal companion's health. And while nutritionally balanced, fresh whole food isn't the cure for every disease that afflicts cats and dogs, it's the very best foundation upon which to build a protocol that can return a sick animal to good health.
Simply put, when your pet's organs must work overtime to digest and absorb species-inappropriate nutrients from a processed diet, it inhibits the body's capacity to achieve and maintain a state of homeostasis. Homeostasis refers to the ability of the body to find and maintain a condition of equilibrium (stability) within its internal environment when dealing with external changes.3
Fortunately, dogs and cats are among the most resilient animals on the planet. They're able to survive on diets they were never designed to eat. However, let's not kid ourselves — degeneration does occur as a result of inappropriate nutrition. It's just that the changes are gradual and often hidden until a disease is full-blown.
In my opinion, we've created dozens of generations of nutritionally compromised pets that suffer from degenerative diseases linked to nutritional deficiencies. It's encouraging to know that more and more pet parents are catching on, which is why biologically appropriate diets are now a rapidly growing segment of the pet food market.
And, thankfully, more and more pet parents are asking manufacturers why they aren't producing species-appropriate diets, leading to many more options (and thereby, competition) being introduced to the market. The quality of commercially available fresh food diets ranges from amazing (all human-grade, organic and free-range ingredients) to terrible (poor-quality foods that haven't been analyzed for nutritional adequacy). So, as always, you must do your homework before deciding which foods to feed.
Why Research on Biologically Appropriate Diets for Pets Is Nonexistent
In the article, Bermingham points out that there is very little published research on biologically appropriate diets for pets. This is absolutely true, and a huge obstacle toward helping more veterinarians and pet owners learn the benefits of nutritionally balanced, fresh food diets. But thankfully, even this is changing with market demand.
Fortunately, there are small studies being conducted here and there, but funding is always a huge hurdle. Big pet food companies like Nestlé Purina and Mars have deep pockets and the ability to conduct all the research they need to develop their own products. This isn't the case in the much smaller biologically appropriate pet food segment.
According to Bermingham, due to this lack of research, studies of biologically appropriate diets for humans and rodents have been extrapolated to cats and dogs. However, humans and rodents are omnivores (both plant and meat eaters), whereas cats are obligate carnivores, meaning they need animal protein, fats and a moisture-rich diet to survive.
A question we should all be asking is why, if the processed pet food industry recognizes this distinction, it persists in producing biologically inappropriate, plant-based dry diets for cats.
Fascinating Results From a Small Finnish Study of Raw Versus Kibble Fed Dogs
In March I visited a veterinary school in Helsinki, Finland to learn more about the amazing work of Dr. Anna Hielm-Björkman, who has studied pet food and raw meat diets in pets for almost 20 years. Her latest research involves studying the levels of homocysteine, a marker of inflammation and chronic disease in the body, relating to diet.
Dr. Björkman's experiment involved four groups of dogs for six months (a quick video summary of this study can be found here). The first group consisted of previously raw fed dogs who were switched to dry food for the second half of the study (the last three months). The second group consisted of dry-fed dogs that were switched to raw food for three months. The third and fourth groups continued eating their regular food (either dry or raw for the full six-month study).
As I would expect, the dogs fed raw food who continued to eat raw food had the lowest homocysteine levels, at 0.17mM (a good thing). The dogs who ate dry food and continued eating dry food had the highest levels of homocysteine, 10 times more than the raw fed group (1.57mM).
Also as expected, the dogs raised on raw food and switched to kibble had a fivefold increase in levels of the disease marker in the body at the completion of the study (0.77mM). What we hope the pet food industry will pay attention to is the fact that the dogs raised on dry food and changed to raw food for three months had a dramatic decrease in the disease marker (0.3mM).
Eating a biologically appropriate diet isn't just trendy, it's healthier. This type of groundbreaking research should be pivotal in changing the way pets are fed and how pet food is produced, if the industry is genuinely focused on improving the health of companion animals through the products they manufacture.
Additional Ongoing Independent Pet Food Research
Mercola Healthy Pets has partnered with CANWI to fund the first comparative study of dry, canned and raw foods and the amount of toxic byproducts found in these foods after processing.
In addition, I just returned from a visit with Italian researchers Dr. Misa Sandri and professor Bruno Stefanon at the University of Udine, who completed a study documenting the profound benefits of a fresh food diet compared to processed dog food on the gut microbiome.4 These results mirror what New Zealand researchers demonstrated earlier this year, which is that raw food diets are healthier (in one way or another) than biologically inappropriate diets.5
One nonprofit group, KetoPet Sanctuary, is using biologically appropriate diets as a powerful adjunctive tool in fighting some of the most aggressive types of canine cancers, with head turning results.
This prompts the question, if raw food diets are powerful enough to address cancer (one of the most diagnosed and devastating diseases plaguing domesticated dogs today), why isn't the pet food industry spending more money researching them? One possible explanation: The biologically inappropriate kibble industry is estimated to generate a whopping 20 billions dollars this year.
Here's Big Pet Food's Argument for Feeding Dogs Plant-Based Diets
Bermingham moves on to dogs, and describes them as "… omnivorous carnivores [that] can eat a wide range of foods to survive." From the article:
"Their ancestors hunted in packs and were competitive feeders after a kill, so they have little control over the amount of food they eat. Dogs are opportunistic scavengers. Genetically, dogs have cognitive and brain function differences from wolves and other wild dogs. There is also genomic signature in domestic dogs that suggests mutation in starch digesting enzymes, allowing dogs to better digest carbohydrates than their wild ancestors."
This mutation in starch-digesting enzymes in domesticated dogs is based on a study published in 2013 that the big pet food companies absolutely love. For more information, watch my interview with holistic veterinarian and author Dr. Doug Knueven, who explains why the study's assumptions and conclusions are based on incomplete data and are generally flawed.
Yes, dogs and humans coevolved,6 with both species expressing epigenetic changes in response to agricultural practices (including the upregulation of amylase production), but this is hardly justification for feeding canines a vegetarian or plant-based diet. I refuse to refer to canines as "omnivorous" because in my opinion, it has been used as justification for the manufacture and sale of processed dog foods loaded with plant-based and other inappropriate ingredients.
Dogs are scavenging, or facultative carnivores, which in general terms means they are primarily meat-eaters, but can survive on plant material alone if necessary. The key word here is survive. To survive is not to thrive. To thrive is to grow vigorously. To survive means simply to stay alive.
One of the arguments for feeding dogs grain or plant-based or even vegetarian diets is the distinction between obligate and scavenging carnivores. It's assumed, since dogs aren't strict carnivores like cats, they can easily transition to a meatless diet. This is a dangerous misconception. I often see dogs referred to as omnivores rather than carnivores. I strongly disagree with this assertion.
Just because dogs fed plant-based diets are able to stay alive doesn't make them omnivores. Taxonomically, dogs are in the Order Carnivora and the family Canidae.
What Cats and Dogs Choose to Eat When They Get to Choose
From the pet food industry journal article:
"When cats were offered three diets with varying macronutrient profiles, they choose a high-protein, high-fat diet. The total consumption of the three diets by cats, when averaged out, showed that cats preferred protein 50 percent to 52 percent by energy, fat 36 percent to 50 percent by energy, and carbohydrate 2 percent to 12 percent by energy.
In the same type of three-diet-offering study, dogs choose a high-fat, moderate-protein diet. The average result for these tests was a preference for 30 percent to 38 percent protein by energy, 59 percent to 63 percent fat by energy, and 3 percent to 7 percent carbohydrate by energy."
It's clear from these study results and others like them that both cats and dogs naturally choose diets very low in carbohydrates. At the risk of sounding like a broken record, that's because low-carb diets are biologically appropriate for carnivorous canines and felines.
And yet, at the end of the article, Bermingham states, "…biologically appropriate diets are fitting for cats, but not necessarily for dogs." That makes absolutely no sense! It almost seems that processed pet food manufacturers have conceded they aren't feeding cats the nutrition their bodies need, but refuse to admit that dogs are carnivores as well, and also need to eat species-appropriate diets.
Determining the Carb Content of Dry Pet Food
If you're interested in learning what percentage of the food you're feeding your dog or cat is made up of carbohydrates, you won't find that info on the package label. So locate the "guaranteed analysis" on the bag of food and apply the following formula:
100% - % protein - % fat - % moisture - % ash (if not listed, use 6 percent)
= % carbs
Fiber is indigestible roughage that doesn't break down into sugar, so you don't have to include it in the formula.
Example, cat food: Royal Canin Indoor Adult Dry Cat Food
100% – 27% protein – 15% fat – 8% moisture – 6% ash =
Example, dog food: Royal Canin Medium Adult Dry Dog Food
100% – 23% protein – 12% fat – 10% moisture – 6% ash =
In both these examples, the amount of carbohydrates far exceeds the amount a cat or dog is able to effectively digest and assimilate. And believe it or not, most grain-free dry formulas are even higher in carbs than regular formulas like the Royal Canin products.
If you're feeding a dry diet, it might be free of grains, but it can't be free of carbs, because carbs are necessary to form kibble. If you look at the package label, you'll see potato, sweet potato, lentils, peas (pea starch), chickpeas, tapioca or another carbohydrate source(s).
Carb-heavy pet food can lead to blood sugar fluctuations, insulin resistance, obesity, diabetes and other health problems in pets. Carb intake above your dog's or cat's daily needs triggers internal enzyme factors to store the excess as body fat.
The Biologically Appropriate Diet I Recommend
The goal should be to mimic your pet's ancestral diet as closely as possible. I recommend feeding a nutritionally balanced, species-appropriate diet, which means food containing high-quality animal protein, moisture, healthy fats and fiber, with low to no starch content.
A nutritionally balanced raw or gently cooked homemade diet is my top choice for pets, but you should only attempt this if you're committed to doing it right. If you don't want to deal with balancing diets at home, a great alternative is to feed a pre-balanced, commercially available raw food. A freeze-dried/dehydrated diet is second best. Human-grade canned food is a mid-range choice, but can be hard to find.
And be sure to incorporate a variety of fresh foods into your pet's diet, too. Blueberries, chia and hemp seeds in coconut oil, raw pumpkin seeds, fermented vegetables and kefir can provide your furry family member with a variety of nutrition and flavors.