A Broken Heart or A Broken Industry? Possible Link Between Canine Dilated Cardiomyopathy and Diet
September 14, 2018
By Sarah Griffiths, DCH
The Food and Drug Administration is currently investigating whether grain-free diets or “boutique diets” may play a role in the development of canine dilated cardiomyopathy. Pet owners are now being warned by their veterinarians that there may be a link to the development of DCM due to an imbalanced diet.
Another popular article states that raw foods might do the same and then note that the addition of taurine made positive differences for dogs diagnosed with DCM:
While raw food diets are being lumped into this category the study is centered around processed foods that contain legumes (such as peas, lentils, chickpeas, etc.) instead of grains. With all the stories going around in the media, we thought we needed to set the record straight.
“Grain-Free” is a popular catchphrase used by the pet food industry these days, suggesting that these diets are healthier than the conventional dry food. Is it really healthier? And is raw part of this category?
To do this, let’s start at the beginning … In the last decade, pet guardians have increasingly questioned the conventional approach of feeding their pets processed food. A stream of this food revolution was the raw food movement. One of the core claims made by the proponents of raw was that fresh meat and some vegetables were the most biologically appropriate foods for dogs and cats, and while dogs and cats could get some calories from grains, it was significantly less beneficial for them as a nutrient source. Today, the pet food market is flooded with “grain-free” foods but many of them are still highly processed foods. The idea behind the benefit of fresh food diets is the presence of minimally processed biologically appropriate ingredients like meats and vegetation as the core of the diet, not the lack of grains. Fresh, unaltered food sources provide the most benefit to animals. Simply, replacing grains with another equally biologically inappropriate ingredient does not mean that it is healthier, especially since it’s still being processed at high temperatures.
Let’s look at some ingredient lists for top grain-free dry foods and raw foods. How do they compare?
Some of the top processed kibble brands of grain-free pet food have the following listed as their first 5 ingredients:
Lamb, Lamb Meal, Pea Protein, Peas, Chickpeas...
Pasture-raised lamb, garbanzo beans (chickpeas), ocean caught whitefish meal, field peas...
Raw grass-fed lamb, lamb meat meal, whole green peas, whole red lentils, raw lamb liver...
Beef, lentils, tomato pomace, sunflower oil, natural flavor...
Deboned Lamb, Lamb Meal, Sweet Potatoes, Peas, Potatoes...
And let’s look at 5 top Canadian raw food brands for the first 5 ingredients:
Lamb muscle meat, lamb liver, bok choy, yams, zucchini….
Whole beef carcass, romaine lettuce, loose-leaf lettuce, bok choi, celery, carrots….
Lamb, Lamb Heart, Lamb Liver, Organic Yam, Organic Romaine Lettuce….
Beef, Beef Heart, Beef Liver, Ground Beef Bone, Broccoli….
Lamb meat, Lamb bone, Green lamb tripe, Lamb offal....
Keep in mind that the top 5 ingredients listed in dry dog food generally make up the majority of the food. The raw diets chosen contain 75% meat/bone and 25% vegetables. The dry foods all contain a combination of meats, legumes and a smaller amount of vegetable ingredients.
The processed pet food model is not equal to feeding a varied fresh food diet. “Grain-free” is a broad term that can be applied to raw diets or processed grain-free dry food and canned food diets. Raw pet foods are considered grain-free because they are composed of fresh meats, veggies, and other fresh food items eg. species-appropriate fresh foods. Grain-free dry food diets are another matter entirely. Grains are often replaced with other types of starches: green peas, chickpeas, lentils, pinto beans and more etc. These foods are used to create a grain-free diet but they still contain a lot of starch and are high in protein compared to grains. Neither the grains or legumes found in dry diets are species-appropriate food sources for dogs or cats and they aren’t fresh either.
Here’s where we need to discuss this; let's start with a discussion about PROTEIN sources. According to AAFCO, pups need 56.3 g/1000 kcal of protein per day and adults need 45 g / 1000 kcal. This is where AAFCO falls down in its transparency about what the definition of protein actually is...... AAFCO does not specify where protein needs to come from. It can come from meat, legumes, even a boiled, ground up leather shoe can literally pass as a protein source. Each one has an entirely different amino acid profile and is not equal. If you’re wanting to feed a natural diet, you need to pay attention to your sources of protein as well as their quality.
The second issue of discussion involves the amino acid taurine which is currently not recognized by AAFCO as essential for canines. It is considered essential for cats because they cannot synthesize it from other dietary substances. The reason taurine is not listed as essential for dogs is that they can synthesize taurine from precursor amino acids methionine and cysteine. That doesn’t necessarily mean that they don’t require some dietary taurine. Methionine and cysteine are very low in legumes but high in meat. These may be the key factors, especially considering that veterinarians are recommending taurine therapy for animals diagnosed with DCM. When taurine is found in high concentrations in the natural diet, it’s most likely there for a reason, even though we might not be able to explain it yet.
Taurine is found in its highest concentrations inside lean muscle meat, heart meat (the heart muscle) of animals and some shellfish ranging between 380-1752 mg per kilogram (beef & chicken meat and organs). Legumes, on the other hand, contain no detectable taurine (garbanzo, lima, red and pinto beans; pinto bean juice, garden and blackeye peas, and lentils). (1) We also need to consider the possibility that unbalanced raw food diets that don’t contain a variety of organ meats could potentially cause problems with an inadequate taurine intake.
Taurine is known to be a contributor to healthy heart function and has been recognized to improve symptoms in heart disease patients including decreased risk of dilated cardiomyopathy (2)
Confused yet? The truth is we are just at the tip of the iceberg of truly understanding the complexities of nutrition and health - for both people and pets. There is much we don’t know, but we do know that a healthy BALANCED diet should consist of a variety of species-appropriate foods and as little processed food as possible. AAFCO is just a guideline but it cannot possibly provide all the answers to dog nutrition. Commercial “grain-free” pet food companies have realized that they can decrease the meat content while increasing the legume content and still meet AAFCO protein requirements. Unfortunately, this decreases the taurine content and completely changes the amino acid profile which may be a factor in the onset of DCM. Because taurine is not recognized as essential for dogs, it isn’t added to commercial diets, however, supplementation seems to be beneficial in cases of DCM and is added to prescription veterinary heart diets for dogs, despite AAFCO's guidelines. (3) (4) (5)
Taurine is also greatly affected (depleted) by heating and rendering (6).
The last note specifically regarding raw diets and DCM: balancing your lean muscle, fats, organ meats, and veggies is paramount for providing enough taurine along with all the other nutrients that AAFCO doesn’t deem to be essential such as live enzymes, real/vs. synthetic vitamins & minerals, DHA, etc. There are lots of people out there who are unknowingly giving too much fat, not enough muscle meat and sometimes not organ meats. All of these factors will decrease your dog’s dietary taurine and overrall amino acid intake.
If you’d like more info on AAFCO and building a complete raw diet, check out these articles:
And for free custom diet planning with us, you can go here:
Development of DCM does have a major genetic component to it but diet certainly plays a factor in how genes behave inside the cell. We will never solve all the questions about diet with laboratory testing of individual ingredients in animal foods. I believe that nutrients found in fresh (unaltered) foods work synergistically and that it's impossible to isolate them and study them separately. They all work together. The food is just as much a living thing as the animal that consumes it. Though this hasn't been proven by science, there are bits and pieces of evidence coming together about this in human and animal nutrition studies. The whole picture would be pretty hard to see through isolated studies and, boy, wouldn’t that cost a fortune?! My advice, stay safe by simply providing a balanced fresh food diet.