Grain-Free Diets and DCM: Some Truths Behind the Hype
Original Post by: NorthPoint Pets & Company
A few months have passed since the FDA released a report about a potential relationship between grain-free pet foods and Dilated Cardiomyopathy or, DCM. We've all had customers walk through the door with concerns, some even have those same concerns shared with their veterinarian. However, very little research and data are available surrounding this potential relationship, and some within the industry have failed to recognize a greater problem. DCM is just one of many concerns pet owners have to face, along with cancer, diabetes, kidney disease, and allergies just to name a few. The reality is that hyper-focusing on avoiding any one of these can increase the risk for the others.
For owners and veterinarians concerned about grain-inclusive or grain-free foods, they are likely concerned about the wrong risk; instead concern should be centered around diets lacking in fresh food, formulation guidelines that are narrowly researched, outdated research, and foods full of toxic chemicals and by-products of food processing. These items on their own pose more of a risk, which is scientifically proven, over any isolated grain-free diet, to the health and longevity of our pets.
Fact is, a result of feeding overly processed and poorly formulated foods for generations has increased susceptibility to various diseases and as a result the prevalence of various types of diseases and conditions has increased as well. This is not unlike the same issues we see in the health of humans as a result of poor diet all over the globe.
In this review we examine the scientific evidence surrounding the complexity of the DCM issue, and what pet owners can do to reduce risks of disease. Before we start, please keep in mind this article is for informational purposes only and is sourced as part of my own research. It is in no way meant to provide medical advice or replace the advice of a qualified veterinarian.
What's Behind the Hype...
If your pet store is like mine you've likely had customers walk through your door that are concerned some pet foods – particularly grain-free pet foods – are causing heart disease in dogs, specifically DCM. Yet, the most recent FDA report tells a different story, one that is complex and cites zero scientific evidence showing a causative relationship between grain-free diets and heart disease. All of these things considered, there are multiple factors that surround this issue – and none of them are simple.
At NorthPoint Pets & Company, we’ve experienced an increased number of clients worried about this issue and to be honest, we haven’t treated DCM concerns any differently than we do anything else. We’ve always focused on feeding real food, as that is the foundation of health. We know this to be true in human nutrition, and we’re finally seeing published data showing the same for dogs. Empowering our clients with this information has resulted in more people converting to raw and cooked diets, or at least adding some fresh food to the bowl. While reports of declining sales have surfaced from all over the country, I’m really proud to say that we’ve continued to grow because of this - particularly with raw products. By taking the time to hear our clients concerns and educate them on a variety of options, they leave confident they are giving their beloved pets what is best for their overall health.
Before examining the FDA investigation and the facts surrounding a potential association between heart disease and grain-free foods it is important to address what the news media failed to do:
Over half of American dogs are overweight, diabetes rates are rising faster than we can measure and cancer is becoming more prevalent not just in the old, but in the young. Also common are kidney disease and liver disease and dogs and cats experiencing more food and environmental sensitivities and allergies than we have ever seen. Diet-mediated dilated cardiomyopathy (DCM) has affected a relatively small number of dogs from 2014 to date, approximately 524 out of an estimated 77 million dogs in the United States - as of the latest FDA report. While this is certainly a concern that warrants further investigation in a timely manner – DCM is not by any means an epidemic. In fact, the FDA states that they believe the potential association between diet and DCM in dogs is a complex scientific issue that may involve multiple factors.... and most likely does.
The Fact is, Few Pets are Truly Healthy
In examining the whole picture, we know that dogs and cats are not “healthy” – a reality that most pet owners either ignore or don’t believe to be true. Now don't get me wrong, although there are many pet owners out there that do take the time to truly understand their pets health needs, there are still so many that aren't as well informed which leads to many of the common problems we get walking through the front of our stores.
Common problems like skin conditions, “dog-smell”, and GI issues are not – and should not be considered healthy; even though we’ve come to accept them as normal. Some of the causality behind “common" problems is that our pets have been, and still are, subject to many detrimental variables over generations and the consequences of such have impacted the overall well-being and susceptibility of varying types of disease. These variables include, but are not limited to: toxins and pollution in the air, water, soil and food supply, overuse of antibiotics and other medication, over-vaccination, poor quality diet, poor breeding practices, poor nutrition, lack of exercise, radiation, I could go on.
It is possible that some, or more likely, each of these factors have contributed to our pet’s susceptibility to a variety of diseases, including DCM. In fact, obesity, diabetes and other issues have known relationships to DCM – all factors that complicate the scientific investigation.
Understanding All the Risk Factors
The good news is that just because an individual is “predisposed” to a particular disease does not mean that they are going to “develop” that disease as the expression of a “bad gene” can be altered by a healthful diet and limiting exposure to toxins and stress. Alternatively, if dogs or cats are constantly exposed to all these risk factors (various toxins, fed a diet lacking vital nutrition, moisture and meat protein, over-vaccinated, overmedicated and deprived of exercise, obesity) much like how they have been for generations, they have a significant risk of developing the disease to which they are predisposed to. This newer field of science, referred to as nutrigenomics, studies the nutrient impact on gene expression. By melding practices from Nutrition, Biology, Medicine, Genomics, and Bio-information, researchers from all over the world have been able to measure just how crucial real food nutrition is.
Let's imagine for a second that an individual was predisposed to heart disease, but they took care of themselves by consuming a diet consisting of fresh foods, including antioxidants along with moderate fat, and sodium, limited unnecessary medications, consumed clean water and exercised to maintain strong cardiac function. These individuals most likely have a lesser chance of developing heart disease.
For the sake of not oversimplifying this concept, a healthy lifestyle for us or our pets does not eliminate the risk of disease, but it does make our genes more resilient, or resistant to letting that disease develop or advance in the body.
FDA Investigation & Reports
The FDA formally announced an investigation into grain-free dog foods potentially having a link to heart disease in dogs in July of 2018. The investigation specifically named those foods containing potatoes, legumes and pulses. Pulses are a subset of legumes and are defined as peas, lentils, chickpeas and other dry beans. Since there is no central reporting agency for canine disease the FDA states that it is unknown how commonly dogs develop Dilated Cardiomyopathy. However, the increase in reports to the FDA may indicate a potential increase in canine DCM in breeds not previously known to be predisposed and it is unclear if cases have been under reported, and continue to be under reported or if there is a significant spike in cases as a result of these diets, or multiple other variables.
Dilated Cardiomyopathy (DCM) is defined as a condition where the heart becomes enlarged and is unable to adequately pump blood. DCM can include mechanical dysfunction and/or electrical dysfunction which leads to sudden collapse and death. As DCM progresses signs include lethargy, loss of appetite, shallow breathing, intolerance to exercise and shortness of breath. This disease is known to occur in dogs and cats, at varying levels of severity and has more than one cause.
Further complicating matters DCM has causation that is likely multi-variable such as genetics, environmental, nutritional, infections, heavy metal exposure, dysbiosis, and even other unknown causes. Further commentary articles, not research articles, from experts examining the issue seemed to state that there is no direct evidence showing causation between DCM and grain-free pet foods – and that it will take several years to determine what the issue or issues are. The most recent FDA report explicitly states they are investigating and gathering more information in an effort to identify whether there is a specific dietary link to the development of DCM, and based on the data collected thus far, they believe the development of DCM is a complex scientific issue that may involve multiple factors.
As retailers, we have seen news outlets and major pet food brands jumping at the opportunity to sow a seed of doubt in the minds of veterinarians and pet parents leading some to make unnecessary, and even health prohibiting changes. Many of these articles are wildly lacking in facts, leaving a carefully crafted short-story that does not afford pet parents, and even some veterinarians, the right to make a well-educated decision. This paired with fast growing social media hysteria are likely the main reasons this has gotten so out of hand.
It's Not Just Grain-Free Foods
It is important to note – out of the dogs diagnosed with DCM, not all of them were consuming a grain-free diet. Even more notable, most dogs were eating dry food in those cases reported to the FDA, which raises the question of this not being a grain-free problem, per se – rather it’s evidence of a knowledge gap in the formulation of processed food. As the report notes, some improved after a diet change from one grain-free diet to another, and this finding, along with the differences identified between dogs fed various grain-free diets, suggested that DCM was not necessarily tied to the grain-free status of the diet.
In addition, many dogs diagnosed with DCM were initially thought to be taurine-deficient, and we’ve since learned that that this problem is far more complex than the presence or digestibility of taurine. We’re now realizing the presence of significant knowledge gaps in regards to small animal nutrition requirements.
Plainly, we do not know enough about what happens to food when we process it beyond a recognizable state to understand its subsequent effect on a pet's health.
Nutritional Knowledge Gap
Static diets are formulated from generalized minimal recommendations by the Association of American Feed Control Officials (AAFCO) and the NRC which are wholly lacking in sound and reasonable research. Static diets are defined as a diet that a dog may eat each day, for their entire life, and that food provides all the nutrition they need.
These minimum nutrient recommendations have been established with research on Beagles as a proxy for all canines regardless of size or breed. These same recommendations also place pregnant bitches in the same category as growing animals – even though we know that nutritional requirements are different.
Additionally, recommendations made by AAFCO correspond to a total nutrient content within the formulation and do not consider the true digestibility of ingredients leading to the potential of a variety of nutrient deficiencies across multiple breeds. Available research demonstrates that taurine, methionine, cystine, carnitine and other nutrient metabolism is varied among sizes and breeds, all of which are variables further complicating this DCM investigation.
Some within the veterinary community have illogically lumped home cooked, canned and raw diets into the “grain-free” category, however, per the FDA report, the vast majority of DCM cases were reported were for dogs consuming dry foods – not “grain-free” raw or “grain-free” cans, causing unnecessary panic at the expense of pet owners feeding responsibly formulated and safely sourced canned and raw foods. It is important for the consumer and pet-owner to understand that these diets are entirely different in formulation, composition and differ in the way they are formulated and metabolized in comparison to overly-processed dry diets. Fresh and unprocessed diets, like raw, will have abundant taurine and natural nutrients which can limit risks of malabsorption and nutrient deficiencies that are common in kibble and other processed diets. Oversimplifying this issue to “grain-free” raw, canned and home-cooked diets is irresponsible and likely causing more harm than good.
Another thing to note is DCM is not a new concern for dogs or cats. In fact, it has been around for a long time. In the 1970's -1980's DCM was prevalent in cats and it was eventually determined that this was due to low concentrations of taurine and animal protein within the commercialized foods. Pet food companies responded by adding taurine through supplementation and additional meat protein which has since seemed to remedy this issue, however it leaves many other concerns unanswered. The supplementation of nutrients and addition of processed meat is still not an ideal example of adequate nutrition and another example of overly processed diets contributing to the overwhelming amount of disease in companion animals.
Since dogs and cats are nutritionally different it is unlikely that adding taurine to any canine diet will be sufficient to solve the current issue in dogs, especially since diet-related canine DCM is likely far more complex. Further complicating matters, the only definitive diagnosis for DCM is an echocardiogram, which the majority of “cases” highlighted within the FDA report lack. Other methods of screening for potential cardiac disease are whole blood taurine, plasma taurine, auscultation, and chest x-ray it is important to understand that these methods are not reliable in the diagnosis of DCM.
There Are Many Complicated Variables
We know that certain breeds are genetically predisposed to DCM. There is no cure for genetic DCM, and conventional veterinary treatment involves the use of diuretics, ACE inhibitors, anti-arrhythmic, and other pharmaceutical agents to reduce stress on the cardiopulmonary system and kidneys to allow the body to tolerate the condition. Unfortunately, these options provide limited relief for a generally short period of time. It’s important to recognize that genetic DCM and other types of DCM, while they often present the same, are different in causation, and sometimes difficult to discern from each other - even when the diet is changed.
DCM can be closely related to diet, meaning that an individual’s susceptibility can be influenced by diet imbalance. Initially, the assumption with current DCM concerns was a lack of taurine in the diet for varying reasons. However, it was determined that this was likely not true for most cases and instead researchers are now considering other factors preventing the body from utilizing taurine and other nutrients – while also keeping in mind that the issue may be something else entirely.
Another theory is that one or more ingredients are interacting with others causing a blocking effect on taurine utilization. The truth is that researchers are unsure exactly what the mechanism behind this condition is, which again highlights the need for further research.
Disproportionate Levels of Macronutrients
DCM aside, all dry foods that have a high carbohydrate content of at least 30% (grain-inclusive AND grain-free) can be a problem for several reasons that most haven’t recognized:
- Ingredients such as potatoes, peas, and other legumes and pulses have been used in grain-inclusive and grain-free dog food for nearly 25 years to provide dietary fiber and protein in limited capacity. It is recognized that use of some of these ingredients at higher than 15% inclusion on a dry matter basis can decrease crude protein digestibility. Since some foods on the market have greater than 40%, and even up to 60%, inclusion this could facilitate higher risk of nutritional deficiencies if nutrient balance is not considered in the formulation. This can also yield inadequate amount of animal protein which may lead to an imbalance or not enough of various nutrients – one of which can be taurine, and too little taurine (taurine deficiency) can result in DCM.
- Some plant-based proteins, like pea or potato protein, can cause malabsorption and inflammatory conditions in humans. While insufficient research is available to suggest the same in pets, it is certainly a reasonable theory to explore. More and more institutions are exploring the similarities in humans and canines and while some still refute the similarities, the stark similarities in types and rates of disease are unquestionable. Logically, these similarities are not surprising considering that by and large humans eat a highly-processed diet full of chemicals, lack exercise, overuse of medication, and live exposed to environmental toxins and pollution, just like their pets.
Before assigning blame to a particular ingredient, set of ingredients or formulation it is prudent first identify knowledge gaps – especially prior to establishing any causation to a particular disease. Further investigation into these inclusion percentages and relationship to canine health and risk factors is needed to understand this relationship. It is known that grains contain precursors to taurine – amino acids cysteine and methionine. Dogs can manufacture taurine from these amino acids, and it was always thought that taurine was not essential for canines – however individual genetics, breed, size and environmental factors may alter an individual minimum and maximum requirements for taurine and other nutrients.
The pet food industry's switch to grains was not exactly fueled by a problem with the actual grains, or grain allergies like most believe. Absent from the discussion on grain-free vs. grain inclusive diets for people - and pets - is the contamination of grains with herbicides, pesticides, mycotoxins, and fertilizers.
There are numerous peer-reviewed articles detailing the disruption many of these contaminants have on normal gut bacteria function and these are the largest reasons more animals and humans are becoming increasingly intolerant to grain and grain products. We’re learning that disruption of vital gut bacteria balance can have devastating effects on the health of the host, including diabetes, obesity, autoimmune disease, cancers, GI issues and even DCM. The contamination of grains in pet food is likely why many pets experienced improvement of various symptoms with the change from grain-inclusive to grain-free.
Pet food can be made of everything from rendered unfit foods for human consumption to ingredients that are 100% organic and probably better than the food we feed ourselves. I’m not necessarily here to split hairs on ingredients and in the types of ingredients that are in our pet’s food. Because is it these ingredients that are causing the problem? Or is it something else? – These are the questions that the experts seem to avoid entirely. When a dog experiences issues related to food we are quick as a society to turn over the bag and blame an ingredient or set of ingredients. However, those ingredients as listed are likely not the problem - rather the quality, processing, and contamination of these ingredients; something you will never find listed on a label.
Pet Food Processing & Chemical Factors
Protein, fat, and carbohydrates go through irreversible denaturation during the heating process of making kibble. Kibble is heated to high temps which creates a chemical change. A Maillard Reaction Product (MRP) is the name for a series of reactions that is the product of sugar (or carbohydrate) and protein when heated. These are also known as AGE's or Advanced Glycated End Products. MRP's are responsible for nutrient loss and associated with diseases like diabetes, cardiovascular disease, kidney disease, loss of cognitive function, allergies, periodontal disease, and chronic inflammation. This can mean things like arthritis, skin and ear issues, an old injury that keeps resurfacing, bloating, IBS, etc. In addition, there is a large amount of research to suggest that they are carcinogenic and accelerate aging.
Heterocyclic amines are MRPs from cooking protein that increases with elevated cooking temperature. This phenomenon is more pronounced in meat than fish – and these increase with temperature and dryness of meat or meat products.
Acrylamides are a chemical that forms naturally from starchy foods during high-temperature cooking. According to the European Food Safety Authority evidence from animal studies shows that acrylamides are genotoxic and carcinogenic: they damage DNA and cause cancer. And since we know so little about animal nutrition is it possible that much of the disease we're seeing – including DCM has at least something to do with the MRP's that are in pet food?
All these big words aside the takeaway is that the process of making kibble can be responsible for a dog's inability to tolerate certain foods in processed form, and for the incidence of certain diseases. It also explains why some dogs are able to tolerate and even thrive when these foods are fresh instead of processed... but this doesn't mean that kibble is bad for dogs either.
We do not currently have enough research that fully explains what happens to food when it is processed beyond a recognizable state. Nor do we have enough epidemiological studies to understand the consequences of feeding processed food diets for generations. Please recognize that this does not mean that you must feed all fresh food – or all kibble, but instead, a variety of both. Variety is the spice of life, and feeding a good quality "kicked up kibble" - thats kibble with the addition of other fresh ingredients - may be the best way to maintain optimal health.
How to Mitigate Risk
Theory always suggested that mixing fresh food and kibble would result in GI distress or cause problems over time. Fortunately, that theory no longer holds much weight. Rather, feeding vegetables and fruit that are high in antioxidants with kibble provide protective effects against MRP's and the onset of disease.
In addition, feeding raw or cooked meat along with kibble provides amino acids, vitamins, and minerals in their most natural form. While research is in the works and isn't yet published, researchers are finding that feeding raw and kibble together actually reduced inflammatory markers for certain diseases, when done properly. There is also a notable but non-peer reviewed case-study of a dog successfully fed fresh food and kibble which suggested that kibble may have digested at the same rate or slightly faster than raw.
Regardless of what method you choose to recommend to your customers, remember that feeding fresh food does not mean only raw or cooked meat. Fresh food such as vegetables and fruit and other healthful toppers on the market today can provide some antioxidant protection against MRP's, provide additional phytonutrients in their most natural form and improve digestive function. In addition, consumption of green, yellow and cruciferous vegetables reduces oxidative stress which can lead to lower incidence of certain cancers, cardiovascular disease, promote liver detoxification, reduce inflammation and positively impact the function of the immune system.
I know there is a lot to unpack here, but the considerations surrounding DCM challenges are extremely complicated, with many unknowns - leaving customers and retailers alike feeling lost and frustrated. After all, nobody within this industry wants to see pets harmed. The reality is that it will be many years before any formal answers are reached. If your customers are concerned and looking for guidance tell them this:
- Currently, there are no formal dietary recommendations for pet owners from the FDA as of the latest report. If your dog is in a risk group (breed, genetic or other underlying condition) it is best to seek advice from your veterinarian on the health status of your pet.
- Some well-versed experts are recommending adding taurine to pets’ diets regardless of what you feed. Adding taurine can be as simple as purchasing a taurine supplement from a trusted source.
- Consideration of fresh foods is advised, since taurine naturally occurs in animal products – not grains – adding items like chicken breast, beef or other animal hearts, sardines, raw goat milk, and other animal products may be beneficial.
Moving from grain-free kibble to "grain-inclusive" kibble is not likely to solve health, longevity or other nutritional challenges as both of these groups are ultra-processed foods that carry well-documented risks highlighted within this blog. Canines everywhere are largely suffering from man-made diseases and conditions such as obesity, type II diabetes, and nutritional deficiency. Most of these can be linked back to feeding low-moisture, high soluble carbohydrate, low meat protein and ultra-processed dry food with high levels of contaminants. While there is a knowledge gap in the nutrition of both ultra-processed and raw, one cannot deny the association between ultra-processed foods and disease prevalence, and progression. It is also evident that feeding fresh foods provide at least some reduced risk of these common diseases and conditions much as they do in humans.
It is imperative for dog owners to understand and practice methods that recognize each individual animal as different and having unique needs. Not any one diet is complete – and no feeding regimen will be successful for all pets and this very practice is what has been detrimental to our pets and brought us to this point. The best advice we can give them as trusted pet professionals is to feed a variety of different foods, implement rotational strategies within brands and among different brands...
And most importantly... add some fresh food to the bowl!
About Nicole Decrisantis
Nicci’s undergraduate and graduate education includes biology, biochemistry and nutrition. In addition, she holds professional certifications in pet nutrition, supplementation, and complementary herbal and homeopathic therapies. When she is not working at her store Northpoint Pets & Company, you will find her traveling to keep up on current research. She annually participates in summits at the University of Helsinki Finland Veterinary School (DogRisk), the Raw Feeding Veterinary Society (RFVS) in the UK and Holistic Actions in the US. She enjoys taking on a challenge and tackling controversial topics within the pet nutrition space with white papers and lecturing locally and at Police K-9 conferences in the US. She currently resides in Connecticut with her husband and 5 dogs - Beau, Taser, Dasso, Trinity and K-9 Mika.