The FDA and many others are trying to determine if there is a link between cases of canine DCM and the affected dogs’ diets. Here’s our take – and suggestions for feeding your dogs.
Article by Mary Straus and Nancy Kerns, published in the Whole Dog Journal, November 2019
Wilbur, pictured above right, was diagnosed with DCM in April 2019 at age 12, after eating a legume-rich, limited-ingredient diet for five years. Six months following a diet change, taurine supplementation, and treatment with pimobendan (Vetmedin), his cardiologist saw marked improvement on his echocardiogram, supporting the positive changes his owner, Stephanie Jones, had seen in his behavior and energy level. Wilbur continues to act as though he is growing younger.
Update
Interest in this topic has waned since no cause has been proven, but cases continue to be reported. Because DCM cannot be treated by diet and supplement changes unless it was caused by diet, the fact that many dogs improve when their diet is changed and they are supplemented with taurine essentially proves a link between diet and DCM, although it does not identify tthe cause. Please read the veterinary article Research homes in on dietary link to heart ailment in dogs, May 2023, for updates. This article talks about possible breed susceptibility, particularly with Golden Retrievers, and agrees with me that pulses are the most likely culprit. Note that the mixed-breed dog above was eating the most named grain-free Acana kibble when he was diagnosed.
Introduction
Food reviews have been a standard feature of WDJ for 22 years, so it’s not a surprise we are asked for dog food recommendations. The inquiries multiply whenever there is any bad news about dog food – and the ongoing mystery about a possible connection between dog diets and a serious heart disease, canine dilated cardiomyopathy (DCM), is definitely bad news.
Depending upon which news outlets you follow, you may be worried about feeding your dog a food that is grain-free, one that contains peas or other legumes, or one that is “boutique” or made with “exotic” ingredients.
If you haven’t been following any of the news, you can catch up by reading our past coverage of the issue, which we have linked in the online version of this article. Suffice to say here that in July 2018, the United States Food & Drug Administration (FDA) announced that it was looking into reports of a possible link between DCM in breeds of dogs that are not considered at genetic risk of the disease and diets containing “peas, lentils, other legume seeds, or potatoes as main ingredients.”
A year later, the FDA published an update to its original announcement, which included detailed data about the cases they were investigating but still offered no guidance regarding how owners could feed their dogs in order to protect them from developing DCM.
We have been analyzing the data that has been released about the diets that were named in the 515 reports being investigated by the FDA. From this analysis, we have developed recommendations that can help you make feeding choices that we believe could protect your dogs from this disease. In the online version of this article, we have included links that will take you to more detailed explanations, should you wish to know more about how we came to our conclusions.
Before we go on, though, please note: Anything you read, including here and in articles written by veterinary nutritionists, is conjecture. No one knows for sure what might explain a link between certain types of diets and DCM in some dogs – or whether there even is a link – although we believe there is.
It’s important to keep in mind that the vast majority of dogs who are fed the diets named in the FDA’s reports do not develop DCM! On the other hand, we know that there are more cases of DCM than those that have been reported (or even diagnosed). So how concerned should you be?
The risk of diet-related DCM is not the same for all dogs. Certain breeds of dogs (or lines within breeds) are susceptible to DCM due to taurine insufficiency, where the amount of taurine (or its precursors, methionine and cysteine) in the diet is enough for most dogs, but not for them. These breeds include the American Cocke r Spani e l , English Setter, Golden Retriever, Labrador Retriever, Newfoundland, and Saint Bernard. If your dog belongs to one of these breeds, then you should be more concerned about what you’re feeding than the average pet owner.
Other breeds are genetically prone to DCM that is not linked to taurine deficiency, including Boxers, Doberman Pinschers, Great Danes, and Irish Wolfhounds. These dogs may be at no greater risk of diet-related DCM, but since we don’t know for sure, owners may want to be more cautious with these breeds than with others.
Large and giant breed dogs are more susceptible to DCM than smaller dogs are. If you have a large dog, you should be more concerned about what you feed than those with small dogs. One of the factors that drew the attention of veterinary cardiologists, however, was seeing DCM in some smaller dogs as well, so even people with small to medium dogs may want to take precautions. Dogs who eat less than would be expected for their size (older or inactive dogs, or those who get too many calories from treats) also may be at increased risk of dietary insufficiencies, including taurine, which might help explain why some small dogs are affected.
Another risk factor is dogs who eat the same food for long periods of time. The initial FDA report stated, “Early reports from the veterinary cardiology community indicate that the dogs consistently ate these foods as their primary source of nutrition for time periods ranging from months to years [emphasis ours].”
The longer you feed the same food, the more likely your dog is to be affected by any nutritional deficiencies or excesses it contains. Those who rotate foods regularly, particularly those who rotate between different brands of foods with different primary ingredients, have less cause for concern than those who always feed the same food to their dogs.
Taurine is considered an essential amino acid for cats, meaning that they require certain amounts in their diet to remain healthy. Taurine is not considered an essential amino acid for dogs because they are capable of making taurine out of two other amino acids that are considered essential in dogs: methionine and cysteine (also referred to as cystine). A series of studies that began in 1997, however, determined that taurine appears to be conditionally essential for some breeds of dogs, and some lines of dogs within certain breeds. In addition to the breeds named in our article, other breeds suspected of developing DCM associated with low blood taurine levels include the Dalmatian, Boxer, Portuguese Water Dog, Alaskan Malamute, Scottish Terrier, Irish Wolfhound.
For this reason, we were disappointed when the latest NRC guidelines were published in 2006 without adding a requirement for taurine. AAFCO finally updated their own guidelines in 2016 based on the NRC revisions, and also failed to require taurine in dog foods.
The European Pet Food Industry Federation (FEDIAF) has guidelines similar to those produced by the Association of American Feed Control Officials (AAFCO). FEDIAF standards for taurine’s precursors, methionine and cysteine, in adult dog foods are higher than AAFCO uses. European guidelines also have a separate category for dogs whose average daily energy intake is less than that expected by AAFCO (in other words, dogs who eat less food for their size need higher nutrient levels in that food). In our experience, most dogs eat less than what AAFCO assumes.
Adult dog guidelines for combined Methionine+Cysteine, expressed in grams per 1,000 kcal:
AAFCO: 1.63 grams
FEDIAF: 1.91-2.21 grams
Adult dog guidelines for combined Methionine+Cysteine, expressed in dry matter percentages:
AAFCO: 0.65%
FEDIAF: 0.76-0.88%
Because some dogs have problems creating enough taurine from its precursors, we would like to see taurine added to all foods. We appreciate the companies that are doing so and believe it to be one criterion you can use to identify responsible companies.
All of our recommendations are based on the assumption that the issue linking diet and DCM is related to taurine deficiency. There are two very good reasons for this. The first is the link between taurine and DCM in cats that was discovered in the 1980s. The second is the link between taurine and DCM in certain dogs being fed lamb and rice diets that first came to light in the 1990s. Because we know that a lack of sufficient taurine or its precursors can cause DCM in otherwise healthy dogs of all breeds and mixed breeds, it appears to be the most likely culprit in this current situation.
Some of the affected dogs in the FDA reports were found to have low blood taurine levels; however, the majority have normal blood taurine levels. Despite this, most dogs diagnosed with what is suspected to be diet-related DCM are given taurine supplementation, regardless of their taurine blood levels, as well as being switched to a different diet and prescribed heart medications. Some dogs improve, others do not. At this time, it’s impossible to know which factors lead to improvement and which are unnecessary.
Until we know more, our recommendations center on avoiding taurine deficiency by increasing the bioavailability of taurine and its precursors, even for dogs who do not appear to be taurine-deficient.
In general, we recommend avoiding the potential at-risk food categories identified below, or at least limiting them to less than half of your dog’s total diet (if you feed more than two types of food). If you cannot avoid these food categories, then we recommend that you look for foods with added taurine, and/or consider supplementing your dog with taurine yourself (see Supplementing Taurine, below), particularly if your dog is at higher risk of developing DCM, as described above.
We know that much of what you have read or heard before concerned “grain-free” diets, and we aren’t specifically making recommendations about this category of foods. Why? Because almost all of the reported grain-free diets fall into one or more of the categories of concern that we identified. Only eight out of 272 reported categorizable diets involved grain-free foods that did not meet any of the criteria we discuss in this article. Three of those were high in flaxseed, which is high in protein and fiber similar to legumes, and so might possibly lead to similar issues, though there are too few data to draw conclusions.
There is nothing about grains themselves that would protect against DCM. Grains are not a source of taurine, which is found only in animal products. While nothing is known for certain yet, we would bet our shirts that any issue with DCM has nothing to do with the absence of grains. We believe that the inclusion of legumes rather than the exclusion of grains is a more likely cause of a link between diet and DCM.
Adding grains to a grain-free diet won’t help to prevent DCM and could actually make the situation worse. Since taurine and its precursors come primarily from animal sources, replacing part of a complete diet with grains will decrease the amount of these amino acids in the overall diet. If you want to add foods to a commercial diet, always look to add animal proteins, such as meat, fish, and eggs.
We have long argued that there is no need to avoid grains in your dog’s diet unless your dog has a problem with a specific grain (food allergy or intolerance leading to itching and scratching or digestive upset). Our dogs eat rice, oatmeal, quinoa, barley, and other grains. We do avoid corn and wheat in non-human-grade dog foods, as feed-grade corn and wheat are more likely to be contaminated with molds and their toxins, which are not destroyed during the processing used to create pet food.
We identified 293 different foods in the 515 reports being investigated by the FDA. We looked at the ingredients and guaranteed analysis of each of these foods, and, just as the FDA’s researchers were no doubt doing, looked for patterns or categories of products to study separately.
We identified four categories of products that might be linked to DCM in at least some dogs. All four start with the letter “L,” which can help to remember them.
Legumes. The FDA reported that 93% of all products involved in the reports they were investigating contained peas and/or lentils. Our analysis confirmed that 89% of the reported foods appeared to contain significant amounts of these ingredients (generally appearing before the first fat or in multiple combinations, sometimes with other legumes).
Lamb. Lamb-based diets are a known risk factor for taurine-deficient DCM. Our analysis found that more than 20% of the foods named in the FDA’s reports were lamb-based.
Limited-ingredient. We were a little surprised to find that limited-ingredient diets were also overrepresented in these reports and we therefore consider them another potential risk factor.
Low-protein. Diets with low protein levels are a known risk factor for DCM. Normal-protein diets that rely on plant proteins, such as from legumes, also appear to pose a higher risk.
Let’s look at each of these “L” food categories of concern.
Legume-rich diets
Who Can You Trust?
Just because a company produces foods that were named in the reports being investigated by the FDA – even many reports – does not mean that company cannot be trusted. The FDA’s investigation found that nearly all the reported products were nutritionally complete based on current guidelines. Whatever is going on is not something that any company could have been reasonably expected to predict. We are far less interested in what has happened in the past than in how companies respond to the information that certain diets may be causing DCM in some dogs.
One of the things we expect responsible companies to begin doing right away is to add taurine to all of their high-legume diets. This is something that can be done quickly, safely, and with relatively little expense. The best companies will add taurine not only to high-legume foods, but also to diets that fall into other at-risk categories, including lamb-based diets, limited-ingredient diets, and diets that are relatively low in protein. ALL companies should already add taurine to their lamb and rice diets; not doing so is a red flag that the company is either unaware of the risk of taurine deficiency for some dogs eating these diets, or doesn’t care.
Pay attention to how companies respond to this issue. One of the ways to do so is to look for added taurine in the ingredient lists of their foods. Note that more than half the Purina foods reported to the FDA were lamb and rice diets without added taurine.
Another important factor that should help to determine how much you can trust a company is how they respond to your inquiries. Don’t put your trust in any company that does not respond to an inquiry, is unable to answer your questions, or refuses to provide the information you requested, especially when asking for nutritional information other than the guaranteed analysis. The best companies will be open and honest, and will make sure your questions are addressed properly, including referring them to the right person to respond when needed.
The FDA found that the vast majority of reported products (93%) contained peas and/or lentils. It seems likely that something about peas and lentils is impacting the availability of taurine or its precursors in the body. This could be due to incomplete plant proteins replacing animal proteins, or fiber from peas and lentils blocking absorption of nutrients, or some other anti-nutritional factors we don’t fully understand. Note there is little correlation between the maximum crude fiber shown in the guaranteed analysis and the amount of dietary fiber in foods.
Peas are a relatively new ingredient whose popularity has exploded in the last 10 years. The fact that so many foods today contain significant amounts of peas (and other legumes) and the increase in the number of dogs that are reportedly developing DCM (especially those in categories not typically associated with this disease) seems significant. Remember, however, that correlation does not equal causation; again, we are speculating, as no one knows the cause at this time.
Legumes are defined as plants whose fruit (seeds) is enclosed in a pod. Legumes found in dog food include peas, lentils, beans (e.g., pinto beans, navy beans, kidney beans, lima beans, fava beans) and chickpeas (garbanzo beans). Pulses, another term commonly used, are the dry, edible seeds of plants in the legume family, including dried peas, beans, lentils and chickpeas. All pulses are legumes but not all legumes are pulses. Because dog foods may contain fresh peas as well as dried, we use “legumes” rather than “pulses” to define this category.
Pulses are high in protein and fiber and low in fat. High-fat legumes such as soybeans and peanuts do not appear to be involved in the DCM issue.
Bottom line on legumes: We recommend avoiding diets with legumes listed high in the ingredient list (before the first fat or oil) or that include several legumes, even if they appear lower in the ingredient list. If you do feed such a diet, it should not have any of the other “L” traits (be lamb-based, limited-ingredient, or contain less than about 30% protein on a dry matter basis [27% as fed, per the guaranteed analysis, for dry foods]). If you feed high-legume foods as a major part of your dog’s diet, look for foods with added taurine, or consider supplementing with taurine yourself.
Lamb-based diets
Nutritionists have known for more than 20 years that certain breeds of dogs were prone to developing DCM when fed lamb and rice diets. Studies indicate this likely has to do with low bioavailability of taurine’s precursors, methionine and cysteine, in lamb meal. Responsible companies began adding taurine to their lamb and rice diets long ago.
Our analysis of foods named in the FDA reports found that more than 20% of these reports involved diets where lamb was the primary meat source; this included several of the foods with the most reports. The FDA’s analysis found lamb was the second-most common animal protein in reported foods (after chicken). Both of these appear to indicate that lamb is overrepresented in the named foods.
We expect that reliable companies already add taurine to their lamb and rice diets. We also would expect that by now they are in the process of adding taurine to their lamb-based diets that also contain legumes.
Bottom line on lamb: We advise avoiding lamb-based diets without added taurine. If you do feed a lamb-based diet, it should not be high in legumes, limited-ingredient, or low in protein. In addition, we would avoid all foods from any company that sells a lamb and rice diet without added taurine (if they hadn’t already been getting that right, we just wouldn’t trust them at all).
Note: We found several diets where lamb meal was listed second in the ingredient list, following a fresh protein such as beef or bison, which was usually the name used on the label. Because dry lamb meal weighs less than fresh meats, these foods contain more lamb than whatever was named first and would be considered lamb-based diets. Pay attention to ingredient lists, not just the name on the package!
Limited-ingredient diets
The first response from a veterinary nutritionist to the initial FDA report about a possible link between diet and DCM warned against “exotic” ingredients, but her list included both lamb and peas, neither of which would be considered exotic these days (see “We Won’t BEG, below). Instead, what we found was an overrepresentation of limited-ingredient diets, many of which contained no ingredients that most people consider exotic. Almost 40% of all reports received by the FDA involved limited-ingredient diets.
The great majority of these diets included peas and/or lentils, but since that was true for all foods, not just limited-ingredient diets, it doesn’t explain why limited-ingredient diets were named in such a large percentage of reports.
We do not recommend feeding limited-ingredient diets to most dogs, as we believe feeding a variety of ingredients is more likely to meet your dog’s nutritional needs. If you feed a limited-ingredient diet due to your dog’s severe food allergies or digestive issues, avoid foods high in legumes or that are lamb-based or relatively low in protein.
As a general rule we also recommend that you avoid feeding most exotic proteins, anything other than beef, chicken, turkey, lamb, and maybe fish. Exotic proteins (such as kangaroo, venison, duck, bison, rabbit, and so on) should be reserved for potential food allergy testing and/or treatment in the future.
Bottom line on limited-ingredient foods: Until we know more, we feel that companies that make limited-ingredient diets should start adding taurine to these foods. If you feel you must feed a limited-ingredient diet that does not include added taurine, we would suggest supplementing your dog with taurine.
One additional note: Kangaroo was the protein used in the single food reported most often to the FDA – Zignature Kangaroo Formula. This food had twice the number of reports (44) as the next food, Acana Singles Lamb & Apple Formula (both limited-ingredient diets). While no research has been done that we’re aware of, it would appear that kangaroo, like lamb, may be associated with low taurine bioavailability.
Low-protein diets
Insufficient dietary protein is a known risk factor for canine DCM. Protein is needed to build lean muscle, and since the heart is a muscle, insufficient protein can also affect the heart.
We found only a small number of reports of very low-protein diets linked to DCM, but most had no other risk factors (no peas or lentils, not lamb-based or limited-ingredient). Several low-protein urinary care and renal prescription diets were reported to the FDA as being possibly linked to DCM. These diets range from 10.9% to 18.1% protein on a dry matter basis (10 to 16% as-fed).
In our opinion, these prescription diets are often fed unnecessarily. In particular, we do not recommend feeding low-protein diets such as Hill’s Prescription Diet u/d to most dogs prone to forming urinary stones, or feeding diets designed for dogs with late-stage kidney disease who are not expected to live very long to dogs with early-stage kidney disease, who may live for years.
In addition, when we looked at all the named diets that did not include peas or lentils, we found a higher percentage of lower-protein diets, and some with mid-level protein but also with plant proteins in the ingredients, such as corn and wheat gluten meals, pea protein, and potato protein.
Plant proteins may be used to replace animal proteins, providing less taurine and its precursors and more fiber and other factors that may interfere with taurine absorption. Avoid foods that contain corn gluten meal or wheat gluten meal; these are poor-quality, incomplete plant proteins primarily found in lower-quality foods. Pea and potato protein may be acceptable if far down in the ingredient list, but we don’t believe they offer much if any nutritional benefit (we’d prefer to see added taurine instead).
Bottom line on low-protein: In general, we advise looking for foods with at least 23% protein DM (21% on the label, also expressed “as fed,” for dry foods), and preferably more. If you feed a diet that contains a significant amount of legumes, or that includes beet pulp or plant proteins, increase this minimum amount of protein to about 30% dry matter (27% as fed for dry foods). If you feel you must feed a diet with less protein than this, we advise supplementing your dog with taurine.
Beet pulp is known to interfere with taurine absorption. A 2016 study published in the Journal of Animal Science and Technology found that beet pulp may contribute to a decrease in taurine levels in dogs, both because it reduces protein digestibility (and thus the availability of the sulfur amino acids methionine and cysteine, taurine’s precursors) and because it increases fecal excretion of taurine.
Beet pulp is commonly used in dog foods as a source of fiber, but because of its effect on taurine, it would be safest to avoid this ingredient in diets with any of our “L’s” of concern (Lamb-based, Legume-rich, Low-protein, or Limited-ingredient).
The FDA also named potatoes and sweet potatoes as suspect ingredients, but we have our doubts about their potential contribution to diet-related DCM. Both of these ingredients have been used in pet food for much longer than peas and other legumes, and neither is used as an alternative to or replacement source of animal protein.
Our analysis supports this hypothesis: All of the reported grain-free dry foods with significant amounts of potatoes or sweet potatoes also fell into one or more of the other at-risk categories. If these ingredients were truly a risk factor, we would have expected to see many foods reported that contained potatoes or sweet potatoes but did not contain legumes and were not lamb-based, limited-ingredient, or low in protein. At this point we do not feel that the data support avoiding foods that contain potatoes or sweet potatoes.
One ingredient in this category concerns us, however: potato protein. We don’t like to see incomplete plant proteins used to replace better quality, pricier animal proteins, or to inflate the protein percentage on the label.
Again, remember that we don’t know for sure if following our guidelines will help your dogs avoid developing DCM, but we believe they are your best option until more is known.
Four types of diets – those rich in legumes (peas, lentils, beans, chickpeas); limited-ingredient diets (especially those that use kangaroo); lamb-based diets; and diets that are low in protein or that rely too much on plant proteins – may be associated with low taurine bioavailability that could lead to DCM, particularly in certain breeds, large dogs, and those who eat less than expected for their size. We believe that limiting how much you feed of these types of diets, and/or supplementing your dogs with taurine, should help keep them safe.
Not everyone can follow the dietary guidelines we offer. Dogs with severe food allergies or intolerances causing serious skin or digestive issues, and those with health conditions that require a specialized diet, may need to stay on their current diet, even if it is a limited-ingredient, lamb-based, high-legume, and/or low-protein food.
In these cases, we recommend supplementing your dog with taurine, a safe and inexpensive way to address at least one suspected cause of DCM. Typical dosages used for dogs known to have low taurine levels are 250 mg twice a day for small dogs (less than 25 lbs); 500 mg twice a day for medium-sized dogs (25-50 lbs), and 1,000 mg twice a day for dogs over 50 lbs. These amounts are safe to give to dogs with normal taurine levels as well.
It is unclear whether supplementing with taurine will help dogs who do not have low blood taurine levels or who remain on a high-legume diet, but it might help and should not cause harm. Because we don’t know for sure that it helps, however, taurine supplementation should not be used as a substitute for rotating through different foods for normal, healthy dogs.
Taurine can also be provided by adding fresh foods to the diet you feed your dogs. Note that taurine is found only in animal, not plant, products. Heart (e.g., beef heart, chicken hearts) has much more taurine than muscle meat or other organs. Dark poultry meat has 10 times more taurine than white meat, with beef, lamb, pork, and fish falling in between. Eggs are high in methionine and cysteine (taurine’s precursors) but have little taurine.
Both cooking and freezing decrease the amount of taurine in foods. The longer a food is cooked or frozen, the more taurine is lost.
Never feed more than about 20% of your dog’s daily calories in fresh foods without also adding supplements needed to make sure the diet remains complete and balanced.
Even before the FDA’s first announcement was made public, veterinary nutritionist Lisa Freeman of Cummings School of Veterinary Medicine at Tufts University had posted an article online with her take on the issue, which was summarized right there in the title: “A Broken Heart: Risk of heart disease in boutique or grain-free diets and exotic ingredients.”
Dr. Freeman characterized diets with certain attributes as particularly risky: those that are “boutique, grain-free, or exotic ingredient diets,” or BEG for short – an acronym that quickly became popular and continues to be in wide use today.
There are several problems with this acronym. First, only the “grain-free” part is clear – and yet, grain-containing foods have also been named in some of the canine DCM reports that the FDA is investigating.
Dr. Freeman’s definition of “exotic ingredients” includes lamb, peas, and other grain substitutes. Even other veterinary nutritionists are confused by this category, describing it as “non-traditional protein sources.” While kangaroo, venison, and other exotic proteins appear in the table entitled “Animal Proteins in Diets Reported to FDA” in the FDA’s 2019 report, chicken, turkey, beef, and many other animal proteins commonly found in pet food also appear in the table.
Dr. Freeman uses the term “boutique” to target small pet food manufacturers, saying they “might be better at marketing than at nutrition and quality control.”
While we agree that some small pet food companies fit that description, there are others with more than adequate knowledge of nutrition and manufacturing to make great food. Also, there is nothing about the size of a company nor the length of its track record that automatically keeps consumers safe. The recent spate of recalls for Hill’s regular and prescription diets that were causing vitamin D toxicity – products that harmed and even killed dogs – proved this point.
Dr. Freeman and others have suggested that dog owners should buy food only from companies that conduct feeding trials – another way of recommending products from large companies, because feeding trials are so expensive that only the largest companies tend to have the money to pay for them. But feeding trials last just six months, not long enough for a diet to cause symptoms of DCM, and no testing for DCM or any other form of heart disease is done in feeding trials.
The FDA’s investigation has not identified any nutritional deficiencies in reported foods, so this issue cannot be blamed on a lack of nutritional knowledge or quality control.
If this is the first you’re hearing about this issue, please don’t panic and immediately switch your dog’s diet, unless your dog is used to eating different foods. Suddenly changing foods is likely to cause digestive upset in dogs that are unused to it. The longer you’ve been feeding the same food, the more likely your dog is to need time to adjust to something different.
Start by replacing very small amounts of the old food with the new. If your dog is doing well, gradually increase the amount of the new food while decreasing the old. This may take just a few days, or up to a few weeks, depending on how long you’ve been feeding the same thing and how sensitive your dog’s digestive system might be.
Stick with new foods that have a similar level of fat to what you’ve been feeding, at least to start with; it’s more likely that a dog will develop digestive issues if switched from a low-fat diet to one that is higher in fat, particularly if the switch is done too quickly or the dog has been on the low-fat diet for a long time.
If your dog is prone to food allergies, it’s likely he will react quickly with itching and scratching if you feed an ingredient that he’s allergic to. Digestive upset may point toward a food or fat intolerance, or may just be the result of trying to switch too quickly; if your dog vomits or has diarrhea, go back to the old diet until he’s back to normal, then try the switch once more, going even more slowly the second time. If your dog continues to have digestive upset with that food, try something else. Keep a journal of which foods you try and the ingredients in each, and you may be able to pinpoint the ones that cause problems for your dog.
If you have been feeding a limited-ingredient diet because your dog tends to have either allergic (itchy) reactions or digestive upset with other foods, here’s what we would recommend. Start by feeding another food in the same line of foods, so that only the protein source changes. Keep track of which proteins your dog has problems with, and which he does well with. Once you know which proteins your dog can tolerate, try another brand of limited-ingredient diet with a protein your dog is okay with. Continue trying different proteins from the same lines, and different brands of foods using those proteins to get a better idea of which ingredients cause problems for your dog. Once you’ve identified the actual ingredients that your dog has trouble with, you can then try branching out into other foods that are not limited-ingredient diets.
We know that many people feed the same food to their dogs all the time because it’s easier, or because they think it’s better (since that’s what dog food companies and many vets recommend), or because they tried a different food once or twice and their dog didn’t like it or didn’t do well on it. In these cases, we still recommend trying to switch your dog to a different diet, or preferably multiple diets using different brands of foods and different primary ingredients. We still believe that this approach is not only more likely to prevent DCM, but also helps prevent food allergies from developing, and provides protection against any nutritional deficiencies or excesses found in any single diet, as well as issues that lead to recalls.
For those who feed a rotational diet, we advise restricting foods in at-risk categories to less than half the overall diet. That means if you feed just one or two foods, neither should be in any of the at-risk groups we describe. If you feed three or four different foods, one can be among the at-risk categories. If you feed five or six different foods, two can be among the at-risk categories. Foods that fit into more than one of the at-risk categories are likely to be a higher risk than foods that fit into just one; the more categories a food fits into, the higher the potential risk. At least half the foods you feed should have: common meats such as chicken, turkey or beef (not lamb), multiple (not limited) ingredients, little or no legumes, and moderate to high protein.
Some people will be upset that we didn’t name all 293 foods that have been reported to the FDA as being possibly connected to DCM. Those people think that if they could just see the list of named foods, they could avoid those and feel safe feeding anything else, but that’s simply not the case. Just because a food was named does not mean it should not be fed, particularly if there were only one or two reports for that food, or if the food has been reformulated or added taurine since the reports were made. We have no way of knowing how valid the reports might be; it could be pure coincidence that a dog developed DCM while eating this food, particularly in breeds known to be genetically prone to DCM, or maybe the dog was recently switched to that food, so it wouldn’t have had time to cause heart problems.
Conversely, just because a food is not named does not mean it is therefore safe to feed. Only a small percentage of suspected cases ever get reported to the FDA, and the likelihood of reports goes down for foods that have a small market share or are new to the market. The list of reported foods is also a moving target: not only will there continue to be more reports, but companies are likely to change the formulations or the names of their foods over time, so that the food currently on the shelf is no longer the same as the food that was reported, or a reported food has the same formulation but a different name. Looking for names is not going to help; knowing what to look for in ingredient lists is far more important.
With that said, there were a few foods that were reported so frequently that, even though they met AAFCO guidelines, we suspect they all contributed in some way to the development of DCM in some dogs. We are going to provide those names, though most now contain added taurine (and we applaud the manufacturers for doing so). We will also show the major ingredients in each food at the time of the reports, to the best of our ability (it is not always possible to know when an ingredient list changed). Below, you will find the seven products that were mentioned most frequently in the reports, with the factors that may be linked to DCM in bold type.
Note: In its June 2019 Update, the FDA provided a chart that listed the 16 companies with the most products listed among the reports it was investigating to date. No information was provided as to which of the foods made by those companies were the ones that were associated with the reports. In our view, this may have been unfairly damaging to certain companies, and offered consumers no information as to which products may have been free of mentions in the reports. We were more interested in trying to figure out which products had the most mentions in the reports, and what they had in common.
(44 reports) Zignature KangarooLimited Ingredient Formula (dry):
Old formula: Kangaroo, Kangaroo Meal,Peas, Chickpeas, Pea Flour, Sunflower Oil (preserved with Citric Acid), Flaxseed, Red Lentils, Green Lentils, Dehydrated Alfalfa Meal, Pea Protein, Natural Flavors, Salt, . . .
Guaranteed Analysis: minimum 26% Protein
Product has added taurine and been reformulated since the first FDA report was released.
In total, Zignature had 12 foods named in a total of 77 reports (33 in addition to the dry Kangaroo Formula). The most named formulas other than Kangaroo were Turkey Formula (6), Lamb Formula (5) and Trout & Salmon Meal Formula (5), all dry foods. Three reports were for canned foods. All Zignature formulas are high in legumes and limited-ingredient. The guaranteed analyses show minimum protein ranging from 26-32%, with the Kangaroo Formula having the lowest protein percentage. The company states that they began supplementing all of their diets with taurine after the FDA reports were released.
(22 reports) Acana Singles Limited IngredientLamb & Apple Formula (dry):
Product has added taurine and been reformulated since the first FDA report was released.
In total, Acana had 18 foods named in a total of 78 reports (56 in addition to the Lamb & Apple Singles Formula). The most named formulas other than Lamb & Apple were Pork & Squash Singles (11), Duck & Pear Singles (8), Heritage Freshwater Fish (5), and Heritage Free-Run Poultry Formula (4). A total of 43 reports were for the Singles (limited-ingredient) line of foods, followed by 16 reports for the Heritage line and 10 for the Regionals line. All reports were for dry foods (Acana does not make canned foods). All reported Acana formulas are high in legumes; all Singles formulas are limited-ingredient. The guaranteed analyses show minimum protein ranging from 27-35%, with a discontinued Singles Formula (Wild Mackerel) having the lowest protein percentage. The company states that they reformulated their Singles foods, adding more meat and taurine supplementation, in September 2018.
Lamb Meal, Peas, Tapioca, Canola Oil (preserved with Mixed Tocopherols), Pea Protein, Pea Fiber, Flaxseed, Natural Flavors, Blueberries, Cranberries, Apples, Carrots, Spinach, Salt . . .
Guaranteed Analysis: minimum 26% Protein
No changes that we’re aware of since the first FDA report was released but already included added taurine.
In total, Earthborn Holistic had 5 foods named in a total of 37 reports (19 in addition to Meadow Feast). A total of 43 reports were for the Singles (limited-ingredient) line of foods, followed by 16 reports for the Heritage line and 10 for the Regionals line. The most named formulas other than Meadow Feast were Coastal Catch (8), and Great Plains Feast (4). All reports were for grain-free dry foods. All reported Earthborn Holistic formulas are high in legumes. The guaranteed analyses show minimum protein ranging from 25-32%, with Meadow Feast having one of the lowest protein percentages. The company states that they have always fortified their grain-free recipes with taurine and other amino acids. Earthborn Holistic is a Midwestern Pet Foods brand.
(12 reports) California Natural Kangaroo & Red Lentils Recipe, Grain Free Limited Ingredient Diet (dry):
Kangaroo, Red Lentils, Green Lentils, Peas, Sunflower Oil, Flaxseed, Pea Fiber, . . .
No changes that we’re aware of since the first FDA report was released; does not contain taurine according to the ingredient list on the Costco website.
In total, Kirkland Signature had 7 foods named in a total of 34 reports (22 in addition to Salmon Meal & Sweet Potato Formula). A total of 5 foods and 32 reports were for the Nature’s Domain line. The most named formulas other than Salmon Meal & Sweet Potato were Nature’s Bounty Organic Chicken & Pea (8), and Nature’s Bounty Turkey Meal & Sweet Potato (3). All reports were for dry foods (Kirkland Signature does not make canned foods). All reported Nature’s Domain formulas are high in legumes. The guaranteed analyses show minimum protein ranging from 20-27%. There is no indication that the company is making any changes to their foods. Kirkland Signature is a Costco brand but the Nature’s Domain line is also available elsewhere.
Product has added taurine since the first FDA report was released.
In total, Taste of the Wild had 11 foods named in a total of 63 reports (52 in addition to Pacific Stream). A total of 5 foods and 32 reports were for the Nature’s Domain line. The most named formulas other than Pacific Stream were High Prairie (10), Sierra Mountain (6), Pine Forest (6), Prey Angus Beef Limited Ingredient Formula (5) and Prey Trout Limited Ingredient Formula (5), with an additional 12 reports for unspecified grain-free formulas and 3 reports for unspecified Prey limited-ingredient formulas. All reports were for dry foods. All reported Taste of the Wild formulas are high in legumes; all Prey formulas are limited-ingredient. The guaranteed analyses show minimum protein ranging from 25-32%. The company states that they began adding taurine to recipes without grains after the initial FDA report was released.
Discusses differing opinions among veterinarians as to the pros and cons of rotation feeding for dogs. Includes quotes from Dr. Joe Bartges, a nutrition consultant at the Veterinary Information Network, and Dr. Paul Pion, one of the veterinarians who first discovered the link between taurine and DCM in cats, supporting feeding a variety of different foods.
Refutes Champion Petfood's claim that the FDA had "concluded there is no scientific evidence that a grain-free diet causes canine dilated cardiomyopathy."
Taurine
History of diet-related links between taurine deficiency and DCM
Retrospective study found no correlation between blood taurine levels and dietary taurine in dogs with DCM, and no difference in outcome when both taurine-deficient and nondeficient dogs were supplemented with taurine.
Study found that taurine excretion was more than three times greater for dogs fed a commercial lamb meal and rice diet compared to those fed a poultry by-product-based diet, though blood levels of taurine remained similar in both groups.
An investigation of the taurine status in a group of related Newfoundlands found that the taurine-deficient dogs had been fed lamb meal and rice diets, and that the taurine deficiency was reversed by a change in diet or methionine supplementation.
Cornell University College of Veterinary Medicine April 23, 2014
Case history of a dog diagnosed with DCM after being fed a homemade vegan diet, with other dogs in the same home eating the same diet similarly affected.
Lists additional breeds: American Cocker Spaniels, Golden Retrievers, Newfoundlands, Labrador Retrievers, Dalmatians, English Bulldogs, Portuguese Water Dogs and Irish Wolfhounds
Study done to determine whether the known risk of taurine-deficiency-induced DCM in dogs fed lamb and rice diets is linked to the inclusion of either rice bran or beet pulp. The study concluded that rice bran was not a contributing factor, but beet pulp may contribute to a decreased taurine status in dogs.
Relationship of taurine to the current FDA investigation
An overview of diet-associated DCM, including known information about a link between taurine deficiency and lamb and rice, low-protein, and high-fiber diets, as well as beet pulp. Includes dosage guidelines for taurine supplementation
Study found that 23 of 24 dogs who developed DCM while eating diets that were grain-free and/or legume-rich improved with diet change and taurine supplementation. No difference was found when L-carnitine was supplemented as well as taurine. Measurement of taurine status in dogs yields inconsistent results.
Journal of Veterinary Cardiology Volume 21, February 2019, Pages 1-9
Study compared several factors in 48 dogs with DCM. It found that the dogs fed a grain-free diet were not taurine deficient, yet seven dogs reevaluated after diet change (six received taurine supplementation as well) all showed improvement.
STERN CARDIAC GENETICS LABORATORY, JOSHUA A. STERN, DVM, PHD, DACVIM (CARDIOLOGY) March 4, 2019
Guidelines for veterinarians regarding taurine testing and treatment. Includes dosage guidelines for taurine supplementation, recommended for all dogs with evidence of DCM even if not taurine deficient.
Journal of Animal Science, Volume 97, Issue 3, March 2019, Pages 983–997
Detailed analysis of amino acid guidelines and history suggests that AAFCO requirements for methionine and cysteine should be increased and that taurine requirements should also be considered. Conclusions mention that “final product formulations should be assessed for nutrient balance and bioavailability, especially when using a limited number of ingredients (emphasis ours).”
A discussion of how the amount of peas and other legumes in pet foods has increased, and why relying heavily on peas and other legumes may not be a good idea, three years before the first FDA report was released. Does not discuss DCM.
Pet nutrition researchers suggested taurine supplementation in dog food as a potential, stopgap measure to prevent DCM while scientists search for hard answers, during a panel discussion at Petfood Forum 2019. One new product was positioned to allow dog owners to do just that for themselves. InClover’s BioVibrant Taurine Plus comes in a shaker container like one used for spices. The dog food topper is marketed as providing “the missing piece for peace of mind.”
“It is pretty well accepted that taurine and L-carnitine supplementation can improve cardiac health especially in dogs with an issue,” Streeter said. “It is likely that if these ingredients were to be supplemented in the diet, they would also help prevent some issues. Since recent research has begun to examine this, it is possible these may become new dietary requirements for dogs in order to help prevent cardiac disease. More controlled studies are also needed, and are underway, which may help us to determine if when certain ingredients, such as legumes or novel protein sources, are used in formulations, the likelihood of altering amino acid status or cardiac parameters increases. If this is found to be the case, the next question we will need to answer is, can supplementation with taurine or L-carnitine be used to prevent cardiac issues from arising, even if these ingredients are used.”
Among dogs diagnosed with canine dilated cardiomyopathy (DCM), veterinary medicine researchers at Tufts University identified a correlation between survival time and changing from a grain-free dog food diet. Study also finds that dogs that received taurine supplementation during the course of their disease also had a significantly longer survival time than those that did not.
Articles written by various authors about the initial increased use of peas and other legumes in dog food.
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Rocky is a Yorkie-Poodle mix who had suffered from digestive problems his whole life. Click on his image to read about the diet his owner finally found to help him.
Pashoshe Fisher, a Chihuahua, was a wonderful, joyful companion to his owner for 19 & a half years. He was on a high quality raw diet for over half his life.
