Why do vets hate grain free
The Farmers Dog has its skeptics: veterinarians
Veterinarians weigh in on The Farmers Dog
Following our publication of an earlier story about The Farmers Dog, we heard from veterinarians who were adamantly against the food and said that they would not feed The Farmers Dog to their own dogs or recommend the food to clients, regardless of cost.
Asked about a sample recipe from The Farmers Dog for turkey, which the companys website generated based on information we entered about five-year-old Labrador Nellie, Korinn Saker, a board-certified veterinary nutritionist at the College of Veterinary Medicine at North Carolina State University who is also an associate professor of clinical nutrition, said:
The fat level is higher than what I would feed to them [her own dogs] and Id prefer a diet that has undergone animal feed tests by AAFCO protocol.
The AAFCO, which stands for the Association of American Feed Control Officials, is a voluntary membership organization that helps to regulate pet food. Dr. Saker also said the fact that the food is grain-free concerns her, but not as much as the first two issues those are, the fat content and the lack of AAFCO testing. She tries to avoid such foods.
We cant say that its [cardiac disease in some dogs] specifically associated with them being on a grain-free diet. There is an association. We dont have any idea yet what the mechanism of action could be for that association but from a nutritionists perspective, I try not to recommend diets that are grain-free right now because there are so many other diets on the market that have grains in them.
Dr. Sakers chief concern was the high-fat level, not the fact that the food is grain-free, nor the fact that the food is not AAFCO tested. If the fat level was a little lower, that would be nice. Its not that there arent diets that are fed to adult maintenance dogs that are that high in level of fat. From my perspective as a nutritionist, when I see a lot of more mature and older dogs that are really overweight and obese, part of the reason is because their diet is high in fat.
Steven Rosenthal is one of the worlds leading experts on dilated cardiomyopathy in dogs and a board-certified veterinary cardiologist who is part of CVCA, a veterinary practice of cardiologists who were among the first to alert the U.S. Food and Drug Administration to the possible connection between grain-free diets and cardiac disease in dogs. Dr. Rosenthal told The Canine Review that the fact that The Farmers Dog is grain-free is not what troubles him. Rather, it is the fact that the food is not tested according to AAFCO standards.
Echoing Dr. Saker, Dr. Rosenthal said he is less troubled about the fact that the food is grain-free.
We do not believe that the exclusive reasoning being the nutritionally mediated heart disease is the fact that the diet is just grain-free any longer, said Rosenthal, who is also working with the FDA on case studies involving grain-free dog food. There are grain-free products that are not associated with heart disease. Being a grain-free product was the initial concern as this was the most obvious factor tying the cases of affected patients together. It is a complex issue that may have a number of factors and at this stage, we are focusing on the high legume content of the diets in affected dogs. I can tell you that I dont personally use that diet for my own dog. I would prefer a diet that has gone through [AAFCO protocol] feed testing, he added.
We also spoke with Martha Cline, a board-certified veterinary nutritionist at Red Bank Veterinary Hospital in Tinton Falls, New Jersey. Dr. Cline said that she does not comment on specific brands, but asked generally about the fact that the food was both grain-free and about the AAFCO statement, she said that while her preference is a diet that is formulated to meet the nutritional levels for the intended life stage AND undergoes AAFCO feeding tests [The Farmers Dog does not do the AAFCO feeding tests], there are also foods that she recommends that just state formulation. Dr. Cline echoed Dr. Rosenthal, saying, The association between diet-associated DCM is still being investigated and there is a lot we dont yet know. The cause is likely multifactorial and likely involves both the diet and the individual dogs response to that diet and how it is fed. All of the doctors agreed that AAFCO testing was a good thing or, as Dr. Rosenthal phrased it, an extra layer of comfort.
A New York veterinarian who asked not to be named offered a more blunt assessment:
I do not feel comfortable with this diet at all. Especially in light of the whole cardiomyopathy (cardiac) issue with boutique diets that are grain-free. Do they have a veterinary nutritionist (someone with a DVM that is boarded in nutrition) guiding them through what they are making? Is the diet AAFCO tested? I would not recommend this diet to any of my patients. If a client wanted to do a home-cooked meal, I would refer them to a veterinary nutritionist that could create the appropriate food and vitamins.
The Farmers Dog responds
Responding to the concern that the recipe is grain-free, the 32-year-old co-founder of The Farmers Dog Brett Podolsky said in a follow-up telephone interview:
Theres absolutely no conclusive evidence whatsoever proving that boutique, grain-free, or exotic BEG is what theyre referring to it as has any connection to DCMAll or 99% of the cases were reported to the FDA about dogs getting DCM were [dogs who eat] dry food. Also, about 40% of dogs in the country are eating grain-free foods, so statistically, its going to work out like that every single time.
Asked about the absence of AAFCO testing, Podolsky said:
What a lot of vets dont realize is that the AAFCO feeding trialsis animal testing. They do it in colonies. And we do not support that. We dont support testing on animals. We are looking into doing something like this.The real reason, though, is that the blood tests that are required will have no indication to prove whether or not the food will cause DCM..AAFCO really needs to change what their requirements are in order to make their feeding trials worthwhile for brands to do. It also is extremely, extremely expensive and boxes out any entering competitors from getting into the business.
Podolsky continued: If you speak to someone like the really reputable people in the formulation world, theyll say that the feeding trials really dont test for enough. Theyll also say that they really believe that this is a protein quality issue.
Podolsky said that fundamentally,
What we believe is that as long as theyre eating fresh food and its a good quality protein and you get all of your amino acids from that protein, a dog would not be at risk for an issue like cardiac disease as a result of diet. Its heartbreaking what these dogs are going through and its sad that a lot of these few vets are pointing at diets that are not causing this.There has been no conclusive evidence to prove that any one type of diet has been causing this. All that we do have to point at is that the vast majority of the diets that the dogs are eating that are getting DCM are dry kibble. The highly processed foods. Were not seeing this pop up in dogs eating fresh food. Were not seeing this pop up in dogs eating actual meat.
Raw food for dogs and cats is natural best?
We often hear of the natural is best. The reason many chose raw feeding is often based on this idea of back to nature. And is one of the reasons for an extensively and fast-growing market in the pet food industry. But what does the evidence say?
Why do people choose to feed raw?
A survey on motivation behind raw feeding found that 26% of respondents said to respect the dogs carnivorous nature when asked to indicate the main reason they chose to provide raw meat-based diets. This was backed up further by two studies that suggested that the most likely reason for choosing raw meat diet (RMD) was that it was perceived to be a more natural choice of diet. This is in agreement with other similar survey-based work; with 69% of owners who fed RMD in one recent study citing they chose the diet as they felt it respected the animal nature of the dog.
Owners beliefs are key
Dog owners who choose to feed raw meat diets have been shown to hold particularly strong beliefs regarding the diet choice for their pet. In the same study owners who choose raw meat diets were suggested to not trust vets as much regarding diet advice; as they believe they have limited knowledge.
For this reason I am expecting that some individuals will not accept the conclusions or discussion in this raw meat based diet discussion series. However, this is not a series to change peoples feeding choices, but to investigate some common misinformation seen in the pet food sphere. The aim is to assess the available evidence; and discuss common claims made by proponents of the diet to assess if they are fully founded on a sound evidence base.
Health benefits?
Some animals do great on a raw meat-based diet, it has numerous claimed health benefits. However actually at present there is not a huge amount of evidence to fully support this. A sad and unavoidable corollary to this natural is best mantra is the idea that processed diets harm pets health. Many proponents of the raw meat based diet claim several reasons for it being superior to commercial processed diets; some of them unsubstantiated. This is not a fair or substantiated claim. And people should not be made to feel like they are doing harm by feeding a complete commercial diet; especially if it is by a company that follows FEDIAF guidelines and engages in feeding trials; such as AAFCO feeding trials.
In a critical review of the evidence surrounding the feeding of raw diets concluded that the evidence for nutritional benefit was low level. There have been some studies since which have attempted to provide evidence in relation to the benefits of raw diets with respect to dental calculus, urinary calcium and oxalate excretion, digestibility and the faecal microbiome and owner-reported reduction in development of atopy when fed in puppyhood. However, the body of published evidence to support the generalised claims of the benefits regarding raw meat diet is lacking; so we are unable to make bold claims yet, and further research is required to substantiate them. Were going to look at this more in part 2.
Myth one: Ancestral diet Dogs are wolves?
One common theme is the idea of reverting back to the diet our dogs ancestors as wolves would have eaten. Investigations into this theory are necessary to ensure we remain objective in our assessment of the appropriateness of these diets when used in a companion animal setting.
The domestication of the dog started some 27,000 and 40,000 years ago with genetic evidence suggesting that dogs split from their wolf ancestors between these periods. Theories of domestication still vary. However it has been suggested that it was originally due to food surplus encouraging wolves to move closer to human settlements and become accustomed to the close contact. Whereas other theories suggest they were encouraged and utilised as hunting aids.
Dogs were wolves but not any more
Over a substantial time period of many thousands of generations dogs evolved away from the wolfs top predator ecological niche. Our domesticated canines have adapted to the niche of omnivorous scavenger commensal on humans as a mutually beneficial relationship. Dogs now, including free-roaming village dogs around the world, similar to the ancestral dogs from which modern breeds were derived, have a very different phenotype to wolves; differing in anatomy, physiology, reproductive strategies, cognition, behaviour (including food acquisition strategies), gut microbiota and diet.
In the wild a species evolutionary diet is adequate for each species to produce as many offspring as they can for survival of the species; but not necessarily optimal for individual animals welfare and lifespan. However, it is the latter we want for our pets: most wild carnivores die before they get old. Even after removing obviously harmful natural factors like parasite burdens and other pathogens; it is unlikely that a species evolutionary diet will be the optimal diet we want for our pets.
Are cats domesticated like dogs?
Pet cats retain many behaviours of their wild ancestor, Felis lybica, the African wildcat. The association between cats and people began about 10,000 years ago (much less time than dogs!) as a mutually beneficial relationship. Cats were attracted to the rodents that would eat harvested grain. This gave the cats a food supply while preserving the grain stores for human use. This mutually beneficial relationship required no modification or genetic selection of the cats innate behaviour.
Cats lack the ability to synthesise (make) a number of important nutrients due to a complete deletion or severe limitation of the enzyme or pathway that makes each nutrient. Important examples include taurine, arginine, and Vitamin A, but there are others.
This inability to make specific amino acids makes meat important in a cats diet. These amino acids may not be found in plants, or the cat cannot use the plants to make them.
Many animals (including dogs and humans) can convert and use other amino acids derived from plants for at least some of these; but cats have lost the ability to synthesise these amino acids. As mentioned above the pathways have been lost or depleted because their natural diet (animal flesh and meat) contains these amino acids in abundance. Without these amino acids in the diet, cats become very sick and ultimately it can be fatal. Therefore their need for animal proteins is much more important than in our companion dogs diet. (Although this doesnt necessarily have to be raw animal protein).
Myth two: Grain in commercial dry/ extruded diets are bad!
I am really pleased to see that when some owners are working to formulate home prepared (whether raw or cooked) diets with evidence-based veterinary nutritionists they are often not shying away from the addition of certain types of grains into their feeding regimes. Carbohydrates certainly play an important role in canine (less so in feline) nutrition.
Sadly, a common myth I see circulating is that grains are bad. And therefore commercial diets that add grains are poor quality fillers this is not true.
Both dogs and cats have the ability to digest and metabolise properly cooked carbohydrates in amounts that are found in commercial pet foods. However, cats cannot metabolise fructose. Because of cats higher protein and fat needs relative to dogs, and lower activity of the enzymes used to digest carbohydrate, foods for healthy cats are usually lower in carbohydrates than foods for healthy dogs.
Altered canine digestion with domestication
Our pet dogs are not actually direct descendants of the grey wolf we have today; they are distant cousins sharing that common ancestor. The dogs ancestor, the grey wolf, is not an obligatecarnivore. And some wolf populations eat much plant matter when seasonally available.In the process of domestication gene expression has changed. The original wolf (and grey wolves today) has a limited (but not negative) ability to digest grains; whereas the domestic dog produces the digestive enzyme amylase in more than adequate qualities to fully break down carbohydrate sources and extract the nutrition they contain.
Specifically interesting is dogs ability to digest starch. A team of Swedish researchers compared the genomes of wolves and dogs and found a big difference between the two is a dogs ability to easily digest starch. It can be concluded that the results indicate that novel adaptations allowing the early ancestors of modern dogs to thrive on a diet rich in starch, relative to the carnivorous diet of wolves, constituted a crucial step in the early domestication of dogs.
How common is a grain allergy?
Furthermore, in the dog world there are actually only very few instances of grain allergy; one of which is epileptoid cramping syndrome, or more specifically paroxysmal dyskinesia in Border Terriers. Where a dog suffers with this disease, a gluten-free diet is genuinely warranted.
Some dogs do exceptionally well on grain-free diets. And anecdotally it appears to help with gastrointestinal issues and skin complaints. Though these health benefits havent yet been clinically proven. And there are a few other reasons why we might see these changes on a grain free diet that is not necessarily just associated with the lack of grain.
However, there have been recent concerns over the role certain grain-free diets have been playing in cardiovascular health; particularly in relation to Dilated Cardiomyopathy (DCM). A disease of the heart that is characterised by the weakening and thinning of the myocardium or heart muscle.
What we know, so far, is that there are some dogs of breeds not known to be genetically prone to DCM that have developed this disease when fed grain free diets, or diets that contain pulses and legumes such as peas, and lentils. We do not currently know the true reason for this, but it could be down to several factors; such as anti-nutrients (natural or synthetic compounds that interfere with the absorption of nutrients) and issues with bioavailability. Developing a full understanding of whats going on will take a number of years. And it will likely be more complex than the current theories; research will continue to support the evidence base and grow our knowledge.
Conclusion
It is impossible to cover all aspects in a short article. But this one aims to cover two of the biggest circulating myths I see when people try to push a raw food diet. One, that dogs should eat their natural diet and two, all commercial diets are full of rubbish and fillers.
Every pet is individual, and no diet is the best I think to claim such a thing is unreasonable
Homemade diets are not without risk, raw diets, whether home prepared or commercial, can carry negative implications to pets, owners and the public, commercial wet and dry diets arent all of the same quality and some are better than others. The ingredient list is not a good way to assess a diets nutritional worth. There are numerous justifiable reasons why many veterinary professionals do not advise raw meat diets. And given the individuality of our pets we should certainly not be pushing one as the best in every circumstance. It is important to weigh up the pros and cons of all diet choices and make informed decisions on the size of risk to our pets and others while feeding certain diet choices.
