Grain-Free Diets & DCM in Dog Food: Everything You Need to Know

As a veterinarian, I am often asked: “What is the place of grains in a dog’s diet?” Should dog food be grain-free? Or grain inclusive? 

Every dog owner is trying to give their pup the healthiest food, but there’s so much noise surrounding this topic that whether you’re a hardliner or agnostic it can be hard to feel confident in your choice. 

Why are grains a concern in pet food? 

The controversy around grains stems from an investigation the FDA began in 2018. The FDA looked into reports of a pattern of heart failure in dogs caused by a disease called “DCM” (dilated cardiomyopathy), and a potential link to grain-free diets as the culprit. 

In 2019, the FDA published their report, stating a “potential association” between DCM and diet. However, no definitive link was ever established. 

It should also be noted that some sources have pointed out issues with the efficacy of the study itself — it was too small to be a truly representative sample size, and some vets appear to have only submitted cases where they already believed grain-free foods to be the culprit. 

However, the government agency’s attention on the subject, and inconclusive findings, was enough to sow reasonable doubt and concern among those who love dogs and take their nutrition seriously.

Nearly 8 years later, the investigation is still open — but no closer to definitive findings. 

In 2022, the FDA shared the following update: “We see this as an ongoing, collaborative scientific venture, of which FDA has just one piece as the regulator of animal food and reviewer of adverse event reports received as part of the pet food early warning and surveillance system."

The good news is reported cases of non-hereditary DCM have gone down, but the concern understandably remains for concerned dog parents. 

Ok, so what exactly is DCM?

A quick definition: 

Dilated cardiomyopathy (DCM) is a disease that causes a dog’s heart muscle to enlarge (dilate) and weaken. Over time, this causes the heart to struggle to effectively circulate blood. Poor circulation can lead to a buildup of fluid in the heart and lungs, known as congestive heart failure. 

Certain larger breeds, such as Doberman Pinschers and Great Danes, are genetically predisposed to DCM.

DCM can lead to severe heart failure and death if not appropriately diagnosed and treated.

What does DCM look like in dogs? 

An official diagnosis requires advanced diagnostics including radiographs (x-rays) and echocardiogram.

There are some externally observable signs that can indicate DCM in dogs, which can include:

• rapid or labored breathing at rest
• coughing or gagging
• pale gums
• weakness
• lethargy
• collapse or fainting

However, these symptoms can also be related to many other underlying issues. And some dogs display no outward signs of illness at early stages, but die suddenly and unexpectedly due to acute heart failure or an arrhythmia (irregular heart rhythm). 

It’s this vagueness of the disease — both the causes and identification of it — that understandably gives so many dog people concern. 

How does DCM link to diet? 

Understandably, many have been desperate to fill this information vacuum with clear guidance. That being said, there has still never been a definitive link proven between grain-inclusive or grain-exclusive diets and DCM. 

There has been some refinement to the nutritional theory regarding DCM since 2018, even though researchers are still unsure of the exact cause or mechanism. 

Despite all the grain debates, one leading hypothesis actually zeroes in on legumes instead. 

As they’re digested, ingredients such as peas, lentils, chickpeas, or other legumes, have been found to inhibit the body’s ability to absorb essential vitamins and minerals as they contain compounds called “anti-nutrients.” These anti-nutrients prevent the body from properly absorbing essential amino acids including taurine. Taurine-deficiency is thought to be the root cause of nutritional DCM. 

 In addition to ingredient lists, the processing of the ingredients also contributes to the quality of the final product. Low quality dog foods are made using extreme quantities of heat and pressure which damage ingredients’ natural nutrients. 

Put simply, many dog foods on the market misrepresent their ingredients, use a high percentage of cheap, protein percentage-boosting ingredients like legumes, and then process them with extreme heat and pressure. 

Together, this results in a low quality product that is unhealthy for dogs to eat every meal of their lives for numerous reasons. But the key one here is that low quality products interfere with dogs’ ability to properly absorb and utilize the essential amino acid taurine — in turn potentially contributing to the development of DCM. Even diets that market themselves as having adequate taurine can still put a dog at risk for DCM as it is the absorption and utilization of taurine, not just the presence in the diet, that is thought to predispose dogs to developing nutritional DCM. 

What should I look for in a high quality pet food?

The safest bet to ensure your dog’s long term health is to feed a high quality daily diet. 

But here are a few questions to ask of any food before selecting it for your dog: 

What does the ingredient list look like?

Companies have lots of tactics for manipulating labels, so they can be hard to navigate. But if there are legumes listed within the first 5 ingredients, they’re likely skimping on high quality meat and using legumes to artificially inflate the protein claims of the food. Grains within the first 5 ingredients can be viewed similarly (though as established, the presence of grains on an ingredient list isn’t itself cause for concern).

How was the food cooked?

Harsh cooking methods like ultra-processing are often used to make a palatable product from cheap ingredients. Low and slow cooking methods, like air drying, avoid damaging the ingredients’ natural nutrients and result in a healthier product. 

What standards was the kitchen held to?

Pet food can legally be made using far lower safety standards than human food — so most pet food companies do exactly that. Pet foods that are made to “human-grade” standards voluntarily hold themselves to a higher, more legally rigorous standard, following FDA guidance for preparing human food. This affects everything from the quality of ingredients permitted to the cleanliness of the facilities they’re prepared in, and results in a tangibly — and more reliably — healthy product. 

Both grain-free and grain-inclusive pet foods can be made to these standards, and these standards are far more impactful to your dog’s long term health than any specific ingredient, brand, or format of food. 

Of course, one of the safest bets is to ask your veterinarian for a recommendation on what food would work best for your dog’s needs!

I suspect my dog has DCM. What should I do? 

First, make an appointment with your veterinarian right away to share your concerns if you spot potential signs of DCM (loss of appetite, pale gums, increased heart rate, coughing, difficulty breathing, periods of weakness, lethargy, and fainting).

Only a vet can help you confirm whether your dog has diet-related DCM, and will prescribe a treatment plan. If they diagnose it, you can also help contribute to the research on the disease by reporting it to the FDA, along with other factors like diet, breed, and lifestyle. 

Are Sundays recipes a risk for DCM? 

No, in short! 

None of our recipes use legumes or potatoes in any way, and they’re all nutritionally balanced without using starchy ingredients. Although a definitive link has not been proven, the existing evidence is strong enough for us to never use any legumes. 

We provide high quality nutrition with real meat, fruits, veggies, and a small amount of whole grains — and cook our food low and slow to preserve the ingredients’ natural nutrients. We hold all of our products to human-grade standards from start to finish for a truly healthy recipe we’re proud to feed to our own dogs. 

Wow, how do I switch to Sundays for Dogs? 

I’m so glad you asked! We’ve made it truly effortless to feed your dog the best nutrition. Just share a few details about your dog to build their profile and select the air-dried recipes that work best for you from turkey, chicken, and USDA beef. All that’s left to do is serve, and we provide portioning guidance too!

Our all-star customer service team is available to support you, whatever you need — and if for any reason you’re left hungry for something else, we offer a 14-day money-back guarantee.