In late September 2020, the Food and Drug Administration (FDA) quietly issued an update on the grain-free pet food and canine dilated cardiomyopathy (DCM) investigation that was a far cry from – and far less publicized than – the initial FDA reports and updates back in 2018 and 2019. In short, Vet-LIRN (the veterinary laboratory network that FDA partnered with for the investigation) closely examined a subset of approximately 150 dogs diagnosed with DCM to identify potential causative and recovery factors. The results show that DCM is a multifactorial issue with potential variables including, but not limited to, breed, age, weight, gastrointestinal disease, atopy, infection and more.

FDA also noted that diet changes were not necessarily responsible for dogs that experienced partial or full recovery since nearly all dogs were also treated with supplemental taurine, pharmaceutical drugs (e.g., pimobendane, ACE inhibitors) as well as other drugs and/or supplements.

Miscommunication, lack of transparency to date

Unbeknownst to most, Kansas State University (KSU) held a virtual scientific forum on September 29, 2020, to explore the emerging issue between DCM and certain pet food diets. The forum provided an opportunity for FDA and other organizations to give an update in a non-public setting, which appeared to serve as a call to action.

To this point, I have covered the DCM topic as it relates to nutrition in July 2019 and September 2019, and as part of a presentation I gave at the VMX veterinary conference in January 2020, on “Ethical Advice on Dietary Recommendations in the Shadow of DCM.”

In all of this coverage, I have been critical not only of how the investigation and data collection for this DCM issue have been conducted but also of the three FDA DCM advisories: the initial one in July 2018, plus the February 2019 and June 2019 follow-ups. This is because there was a significant level of miscommunication of information, but also significant issues in the way the information was disseminated with a lack of transparency to the veterinary, pet food industry and pet owner communities.

FDA’s Center for Veterinary Medicine (CVM) did provide some critical albeit not highly publicized updates (maybe because they were inconvenient) during the most recent forum in September 2020. Yet, this has left me scratching my head! Not to fear, though, we’ll cover those updates here.

FDA update part 1: Not surprising but frustrating

In opening remarks for the KSU forum, Steven M. Solomon, DVM, MPH, director of CVM, provided the rationale and reasoning (excuses) for why they initiated the communications with the public back in July 2018. He further explained why FDA provided updates per Freedom of Information Act (FOIA) requests, yet he failed to explain the rationale behind the summary of 16 pet food brands named in June 2019 and presented in a manner that claimed all the foods were grain-free. The problem was, some foods were indeed grain-based (note: not very transparent).

To some of us, what Solomon discussed did not come as a great surprise. In fact, it was rather frustrating since what he alluded to and summarized was exactly what those of us who actually reviewed the data have been saying since the beginning of the DCM investigation. After the initial FDA announcement in 2018, an uptick in cardiac-related cases were reported to CVM, totaling approximately 1,100 cases.   That means 45% of the approximately 2,000 cases originally reported were not DCM at all. Further, after analyzing diet history with those dogs, they came to the realization that, “The data did not show any correlations related to protein.” Now, just think of how much taxpayer money they would have saved if they had read my article in July 2019!

Solomon also stated:

“Dogs in cases submitted to FDA were reported to have consumed diets containing high proportions of pulse ingredients, which are dried legume seeds, including peas, chickpeas and lentils.” And, “It is important to note that pulse ingredients have been used in pet food for a long time, and we have no evidence to indicate that they are inherently dangerous. However, CVM’s data show they are used in these grain-free diets in greater proportion than in grain-containing formulas, which means there is an area to investigate further.”

Well, duh! FDA’s original request was for cases involving grain-free pet food, and that is what people keep sending in (which has resulted in a biased and polluted data pool, but that’s a conversation for another day). Perhaps if FDA asked veterinarians and the public to send in all cases, regardless of diet, we may have seen something else, like the whole picture.

In fact, though FDA asked for cases involving grain-free pet foods, they still received roughly 10% grain-based foods reported. Which is why I keep saying, the February 2019 Vet-LIRN update was the best provided, since both categories of food were high in total dietary fiber (not crude fiber). Many nutritionists (but not all) have known for years that increases in total dietary fiber reduce digestibility and lower taurine status. Also, for some reason, CVM failed to realize that 88% of the foods were dry kibble.

What the investigation should entail

During the September virtual forum, Solomon’s closing remarks included this statement: “What we at CVM have learned since these cases first started coming to our attention is that DCM is a scientifically complex, multifaceted issue.”

For those crying wolf, take note of that sentence. Even with the biased data pool, this is a relatively small number of cases with an incredibly high number of variables. In other words, this issue cannot simply be boiled down to blaming any one particular ingredient or set of ingredients. That is an oversimplified and shortsighted approach that will never yield any meaningful answers. Instead, we should be investigating nutrient levels along with availability within all pet food formats in order to solve a variety of pet food challenges – including DCM. That is assuming any of these DCM cases are truly tied to pet foods.

Finally, Solomon acknowledged:

“This is one of our ongoing struggles: choosing terminology that is scientifically accurate, understandable to pet owners and that does not cast a shadow over products that are otherwise known to be healthful and safe. I appreciate the fact that FDA’s voice is the voice veterinarians and pet owners listen to, yet too often our messages have been repeated inaccurately by third parties. The result is that in the internet age of phenomenally fast sound bites, complex scientific messaging is often lost in translation. We have tried to be careful in our messaging, and we recognize going forward not to speak on this topic publicly unless we are clarifying information or have something substantive to share.” 

I think we can all agree on each word of the last paragraph! It especially holds true when there is no data to put people into the state of panic that FDA, a couple of universities and countless veterinary clinics did to consumers. Still, I will take Solomon’s statement as an “olive branch” and a rather weak apology for the debacle this has become.

FDA update part 2: Still areas of concern

During the forum at KSU, Drs. Jennifer Jones, Lauren Carey and Lee Anne Palmer of CVM also gave a presentation. Interesting takeaways and areas of concern from my point of view include:

  • There was a surge in DCM cases reported following each FDA update;
  • Potential association of DCM to Lyme disease and Chagas disease has been noted;
  • FDA noted that data from these dogs is fluid and changing (e.g., not conclusive);
  • Taurine status, congestive heart failure, age, weight and left ventricular size and function does not appear to impact recovery time;
  • Label evaluations from reported products are being conducted from an ingredient or ingredient class standpoint only;
  • Further, it is evident that the presenters of this update (whom, by the way, are not nutritionists or veterinary nutritionists) are unaware of the definition nuances of meat meal, chicken meal, meat by-products or chicken by-products according to the Association of American of Feed Control Officials;
  • It does not appear the VET-LIRN team examined total dietary fiber as a potential factor in taurine or other nutrient bioavailability.

Suggestions for CVM and the pet food industry

A simple yet major oversight in this entire investigation is that the investigative bodies and academic community have yet to consider and/or conduct true nutrient analysis and digestibility testing on implicated pet foods. This is even more concerning considering we are approximately two and a half years into this debacle without any advancement into the causation(s) behind DCM.

Investigating ingredients or classes of ingredients does not make logical sense because they contain countless nutrients (e.g., amino acids, fatty acids, vitamins, minerals etc.) that can supply nutrition or work as anti-nutrients. Said simply, we cannot truly know how an animal’s body will assimilate a given nutrient or set of nutrients until we measure it!

This becomes more complicated with the addition of mechanical and heat processing in making pet foods – another reason why it is so important to measure nutrient inclusion and digestibility of all pet foods. If placing blame on ingredients is the investigative path we continue to take, you can rest assured no tangible or actionable progress will be made on the issue, period. 

If you were to ask pet food manufacturers for actual digestibility results and processing conditions, you’d be surprised how many can’t and won’t answer that question because the reality is that most pet foods on the market are not validated. And if these facts weren’t enough for you as a manufacturer to conduct digestibility studies on your products, you should know that scientists worldwide are starting to investigate the impacts of pet food processing on pet health, including inflammatory diseases via the production of certain Mallaird reaction products like advanced glycation end-products that are shown to impact cardiovascular disease in humans.

Wouldn’t it be nice …?

The investigation lacks both practical and critical thinking approaches to a complex issue. It’s disappointing and rather embarrassing to see academics and professional investigators have a close-minded and frankly underwhelming approach to the entire investigation.

It’s no secret there are substantial knowledge gaps in the field of companion animal nutrition. Wouldn’t it be nice if we viewed the DCM issue as an opportunity to close some of those gaps for the sake of animal health, rather than cut out an entire segment of the pet food industry without adequate evidence? Wouldn’t it be nice if some of the so-called small brands of pet food stepped up to the plate and nutritionally validated their foods (with typical nutrient analysis and digestibility studies), since such validation would have arguably cost less than their taurine-rich or ancient-grain marketing campaigns? Wouldn’t it have been nice for consumers to have the industry advocate for them, instead of leaving the entire pet care community (veterinarians, retailers and consumers) unable to trust the pet food industry? Yeah, it would be nice. 

Although we may think this issue over, think about the massive flood of ancient grain products hitting the marketplace right now with even less data to support their existence than we have for grain-free. For the record, taurine comes from animal protein sources or via supplementation, not from grains, ancient grains or legumes.