The rising popularity of grain-free dog food is nothing to overlook. Many of us view our dogs not just as pets but as members of the family. So of course, we want to ensure the best quality of care possible to guarantee our pets’ health. One of the main ways we can do this is through their diet. Low carb and gluten-free diets have taken hold of human nutritional trends, and people are sharing the trend with their furry friends. As of 2017, over 40% of dog foods on the market in the US were grain-free. But is grain-free good for dogs? Let’s find out.

Regular vs. Grain-Free Dog Food

What is Grain-Free Diet for Dogs?

Everyone wants the best for their furry friends, especially when it comes to kibble in the bowl. As people become more aware of the nutrients and chemicals in our own diets, dog lovers eyes quickly turned to the nutrition labels on the back of their dogs’ food. Odds are you probably have a friend or two boasting about the benefits of gluten-free or paleo diets for human health.

is grain-free good for dogs
One of the many grain-free dog food products on the market

Similarly inspired grain-free dog diets have become more popular in the past few years, with some closed Facebook groups touting members in the thousands promoting natural, raw, and especially grain-free foods. However, it is unclear if the science is behind this new trend in doggy diets. From social media to scientific journals, we’re taking an in depth look at grain-free diets to determine if this fad is a faux-“paw” for your furry friend.

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Grain-free diets can be dry or wet, commercially produced or home-made, but their common thread is what they lack: no corn, soy, wheat, rice, barley, or any other grain. This is akin to a gluten-free diet in humans.

Is Grain-Free Good for Dogs? Benefits of Grain-Free Dog Food

Studies have estimated that wheat and soy represent 13-15% and 6% of dog food sensitivities, respectively. If your dog has been showing signs or symptoms of a food allergy or sensitivity, it is possible that wheat or soy could be the culprit.

Symptoms of food sensitivity include vomiting, diarrhea, flatulence, decreased growth in young dogs, coughing, sneezing, increased scratching, hair loss, red or inflamed skin, and chronic ear problems. If these symptoms sound familiar, you may want to consult your trusted veterinarian and consider a grain-free diet for your dog.

Proponents of grain-free dog food say it can improve your dogs’ digestion, increase energy, improve weight management, and decrease food allergy issues. However, it is unclear if there is much science to back up these claims. Of course, if your dog has grain-related allergy issues, finding an appropriate grain-free dog food will be the best solution for their health. But it may not be necessary for all dogs.

Grain-Free Diets And DCM: The Long Debate

Brief Explanation of DCM

Before we move on to finding the answer to the question of “is grain-free good for dogs?” let’s break down the heart of the issue: Canine Dilated Cardiomyopathy (DCM). DCM is a disease that impacts a dog’s heart muscles resulting in an enlarged heart. The heart’s pumping function diminishes, meaning it is unable to effectively pump blood through the vascular system. This leads to fluid leaking into and building up in the chest and abdomen.

is grain-free good for dogs - dcm and taurine deficiency link

Common symptoms of DCM are caused by the lack of oxygenated blood circulating and the buildup of blood in the lungs. Symptoms include lethargy, weakness, collapse, weight loss, increased breathing rate or difficulty breathing, coughing, and abdominal distention. DCM can lead to the development of cardiac arrhythmias and congestive heart failure, which can cause sudden death.

A variety of factors can cause DCM, including genetics, infections, immune disorders, toxins, and nutritional defects. One such nutritional factor, taurine deficiency, has been recognized since the 1980s as an important precursor to the development of DCM.

What is Taurine And Why Is It Important For Dogs?

So what exactly is taurine and why is it so important for my dog? Taurine is a unique amino acid. Instead of helping to build proteins as most amino acids do, taurine stays free-floating in the tissue and evidence shows it has important roles in cardiac function and bile acid metabolism.

Unlike cats, taurine is normally not considered an essential amino acid for dogs because they can create it themselves from the precursors cysteine and methionine. So as long as the precursors are present in their food in sufficient amounts, dogs shouldn’t have any issues with taurine synthesis.

Large and giant dog breeds with a genetic predisposition to DCM include Great Danes, Boxers, Newfoundlands, Irish Wolfhounds, Saint Bernards, Portuguese Water Dogs, and Doberman Pinschers. While it is less common with smaller dogs, American and English Cocker Spaniels still have a genetic risk. Additionally, studies suggest Golden Retrievers and American Cocker Spaniels have a predisposition to taurine deficiency.

What Exactly Was the FDA Report on DCM and Grain-Free Diets?

So is grain-free good for dogs and why are we talking about amino acids and arrhythmias?

In 2018, the FDA released a report warning about a possible link between grain-free diets for dogs and the development of canine DCM. This report was mainly concerning because it noted DCM occurring in breeds without a genetic predisposition.

The initial report did not include any numbers or statistics, but noted that the cases frequently involved dogs fed grain-free dog food with multiple legumes (including peas, lentils, and other seeds of legumes) or potatoes, and their protein, starch, and fiber sources as main ingredients.

A year later, the FDA released another article detailing the cases of 560 dogs and 14 cats with DCM, as reported to the FDA between January 1, 2014 and April 30, 2019.

Of the cases where dietary information was included, 90% of products were labeled grain-free, 93% included peas and/or lentils as main ingredients, and 42% contained potatoes/sweet potatoes.

Initially, it was thought that these grain-free foods might be insufficient in taurine or its precursors. However, it was reported that almost all the grain-free products exceeded the minimum nutritional requirements, indicating that other factors might be inhibiting taurine status in dogs.

In both reports, the FDA stated they are still gathering information to understand if and how taurine absorption and excretion plays a role in canine DCM.

Does Grain-Free Dog Food Cause Heart Problems?

With over 500 cases reported to the FDA, dog owners are right to question “is grain-free good for dogs?” But metabolic sciences are difficult to say the least, so the problem might not be whether or not the foods are grain-free, but the substitutes they use instead.

Without cereal grains, commercial dog food producers substitute peas, lentils, legumes, potatoes, and other pulses (seeds of legumes). These plants tend to have higher protein levels than cereal grains, but less available taurine and taurine precursors. Additionally, many grain-free dog foods try to limit the use of animal byproducts, which consequentially might decrease levels of dietary taurine. Organ meat is notably high in taurine and is often included as a byproduct in dog foods.

Additionally, not all meat protein sources are created equal. Some, like rabbit or lamb meal, are surprisingly low in taurine or the amino acid precursors.

Other factors, such as high levels of dietary fiber may also impact reabsorption of taurine in the colon. If more taurine is excreted than is synthesized, then the taurine recycling system in the body can be skewed. A 2020 study on the impacts of grain-free diets on Beagles indicated that grain-free dog foods increased bile acid excretion but did not impact taurine levels. A study on Labrador Retrievers yielded similar results. However, both these studies had small sample sizes and must be followed up with more research.

Does Taurine Deficiency Justify Linking DCM and Grain-Free Diets?

The link between taurine deficiency and DCM is well established, however, it is premature at this time to link DCM and grain-free diets.

In fact, not every dog diagnosed with DCM thought to be linked to grain-free food had low levels of taurine. This may indicate other factors also have a role in DCM development, such as inadequate levels of certain other amino acids.

A study released in 2019 noted one such amino acid, carnitine, which has also been linked to development of DCM. Plant-based proteins do not contain carnitine and thus could contribute to deficiencies. This study also pointed out that various factors can influence taurine synthesis and absorption in dogs, such as sex and size., while nutritional factors can increase dietary requirement for taurine, reduce the supply, or increase excretion.

Does Breed Play a Role in Taurine Deficiency?

Recently, some studies have looked into breed-specific impacts of grain-free diets. One such study was conducted by veterinary cardiologist Dr. Joshua Stern from the University of California at Davis. His and other research suggest that Golden Retrievers might have a genetic predisposition to taurine deficiency.

Taurine deficiency has been linked with certain diets in several breeds, such as the Newfoundland, American Cocker Spaniels, English Setter, Labrador Retriever, and several others. Further studies are needed to investigate genetic predispositions to taurine deficiency in other breeds.

Shortcomings of the AVMA and FDA Reports

In situations like these, it is important to remember that science is a process. Most studies have to be repeated multiple times in order to confirm the results and negate any impacts from bias or methodology. So when initial reports come out, sometimes we have to wait years before a proper consensus can be concluded.

That being said, there are shortcomings of the FDA report, causing further muddying of waters in an effort to find the answer to “is grain-free good for dogs?”

For example, there is no standard reporting system for dog diseases like we use the Center for Disease Control for human diseases. Thus, we don’t know the typical rate of occurrence for diseases like DCM. Essentially, we cannot claim that cases of DCM have been increasing if we do not know what the standard rate of occurrence was before.

Additionally, the FDA is only requesting veterinarians to report cases of DCM with a suspected link to diet, not all cases of DCM. So we are still not establishing the standard rate of occurrence and building an implicit bias into the body of data. While 560 cases is a notable sample size, it still pales in comparison to the American Veterinary Medical Association’s reported estimates of 77 million pet dogs in the US.

The FDA also reported that breed-specific social media groups for breeds such as Golden Retrievers caused a reporting bias by raising awareness of taurine deficiency and DCM and encouraging owners and vets to report cases to the FDA. Furthermore, diagnostic testing can be very expensive, leading to underreporting.

Other Possible Effects of a Grain-Free Diet

So is grain-free good for dogs, or a mistake? Any diet that relies too heavily on limited ingredients can result in nutritional imbalances, especially if your dog is fed the same food for extended periods (a static diet). Nutritional deficiencies can cause fur loss, skin diseases, infections, lethargy, irregular bowel movements and a variety of other symptoms.

So, Is Grain-Free Good For Dogs, or Bad?

Is grain-free good for dogs? When it comes down to it, there is no clear cut answer yet. Our understanding of dog metabolism and the mechanics behind diet based DCM development is at best, incomplete. Out of an abundance of caution you may want to avoid feeding your dog a completely grain-free diet. Or at least avoid the commercial brands named most often in the FDA case (see FAQ section below).

is grain-free good for dogs
Rachel Ray Nutrish brand dog food was named in the FDA report.

What Are The Safest Foods For My Dog?

If you are interested in pursuing a grain-free diet for your dog at this time, make sure you are paying attention to the other ingredients as well. Many dogs also do well on single grain dog foods. Try to avoid a static diet, incorporate treats, multivitamins, and other supplements in order to meet all nutritional needs. A rotation of foods with muscle meat, organ meat, vegetables, and fruits is best to ensure a full spectrum of nutrients.

If you want to use grain-free dog foods, try incorporating them over time by alternating between your current food and your grain-free choice. Some dogs can have issues with abrupt changes so this may help them adjust.

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Is Grain-Free Good For Dogs? FAQs

Does grain-free dog food cause DCM?

Short answer- possibly. If you are concerned about your dog’s health, contact your vet for testing.

What Should You Do if Your Dog Is on a Grain-Free Diet?

If your dog is a purebred or mix of a breed with a genetic predisposition to DCM or taurine deficiency and is currently on a grain-free diet, it is best to consult your local veterinarian.

Which breeds are more susceptible to taurine deficiency?

Large and giant dog breeds with a genetic predisposition to DCM include Great Danes, Boxers, Newfoundlands, Irish Wolfhounds, Saint Bernards, Portuguese Water Dogs, and Doberman Pinschers. While it is less common with smaller dogs, American and English Cocker Spaniels still have a genetic risk. Additionally, studies suggest Golden Retrievers and American Cocker Spaniels have a predisposition to taurine deficiency.

What brands of grain-free dog food might cause heart disease?

The brands named most frequently in cases reported to the FDA include: Acana, Zignature, Taste of the Wild, 4Health, Earthborn Holistic, Blue Buffalo, Nature’s Domain, Fromm, Merrick, California Natural, Natural Balance, Orijen, Nature’s Variety, NutriSource, Nutro, and Rachel Ray Nutrish.


The information on this page is for informational purposes only. It is not intended to be a substitute for qualified professional veterinary advice, diagnosis, or treatment. Always seek the advice of your veterinarian or other qualified animal health provider with any questions you may have.