Grain-Free Dog Food and Heart Disease: What the Evidence Says

What is this about?

In 2018 the FDA started looking into reports of dilated cardiomyopathy in dogs eating certain diets. It is a disease where the heart muscle grows weak and enlarged. Some of the dogs were breeds that rarely get it. In public, the whole story got squashed down to one line: "grain-free food causes heart disease."

That compression is wrong in both directions. Something real prompted the investigation. But causation was never established, and the pattern in the data is not the one the headline describes.

What the FDA actually said, and where it stands

The FDA's position on causation has been consistent and is worth reading directly rather than through a headline. It has stated that it has not established why certain diets may be associated with the condition in some dogs, and that it has no definitive information indicating that the diets are inherently unsafe and need to be removed from the market. It also noted that adverse event reports by themselves do not supply sufficient data to establish a causal relationship.

There has never been a recall, or a request for one. The most recent substantive public update was 23 December 2022, when the agency said it did not intend to release further updates until there was meaningful new scientific information to share. That is where matters still stand: a pause, not a retraction, and not a conclusion either way.

Peas, not the absence of grain

This is the part most coverage gets wrong. Asked directly whether this is an issue with only grain-free diets, the FDA's answer was no: reports involved both grain-free and grain-containing diets. What the reported products had in common was different:

A telling detail: soy is a legume, and no signal appeared for it. The pattern is specific to pulses (peas and lentils) rather than to legumes generally or to grain-free formulation as such.

The animal protein made no difference either. The FDA's own summary was that protein sources varied widely and no one animal protein source was predominant.

The most direct experiment we have supports the pulse reading. A 28-day trial compared three diets: white rice, whole lentil, and wrinkled pea. The wrinkled pea diet came with weaker heart function measures. The lentil diet did not (Quilliam et al., 2023). It was small and short, and no dog actually developed the disease. The changes were too small to see from the outside. But the direction fits.

The taurine misconception

The early explanation was taurine deficiency, since taurine-related heart disease is well documented in cats. In dogs, that explanation has largely not held up.

In the largest prospective study, none of the 60 dogs with diet-associated heart disease were taurine deficient, and many had high blood taurine. The researchers suggested the high readings might reflect taurine leaking out of damaged heart cells, which is close to the opposite of the deficiency theory (Freeman et al., 2022).

The clear exception is Golden Retrievers. One study looked at 24 of them who had both low taurine and the disease. Twenty-three of the 24 were eating grain-free or legume-heavy food. Twenty-three of the 24 got better after a diet change plus taurine supplements (Kaplan et al., 2018). Genetics likely plays a part. Worth noting: this is one of the very few studies in this whole area with no company funding behind it.

One point both opposing camps have arrived at independently, which makes it unusually trustworthy: blood taurine is an unreliable measure in dogs, since muscle levels can fall while blood levels look normal.

Nobody in this debate is neutral

You should know who is paying for the research on each side, because it is close to symmetrical.

The academic groups that raised the alarm are funded by Purina, Hill's, Royal Canin and Mars: the grain-inclusive incumbents that lost market share to grain-free. The studies finding no effect are funded by pulse growers, grain-free manufacturers, and consultancies working for brands named in the FDA reports. There is no clean side, and we are not a clean side either.

Where AlphaPak sits, and what we will not claim

The factual part: neither of our recipes contains peas, lentils, chickpeas, or soy. There are no pulses in them at all. The only starchy plant ingredients are sweet potato and, in the Chicken recipe, pumpkin. You can read the full ingredient lists yourself. Both recipes also contain heart muscle, which is the richest natural food source of taurine, though we have not had taurine assayed, so we are not going to put a number on it.

The part we will not claim: that this makes our food safe from heart disease. It does not, and nobody can honestly tell you their food is. About 88% of the FDA's reports involved dry food and only nine involved raw. But those are raw counts with no denominator. Dry kibble is the overwhelming majority of what dogs eat, so a small market category produces few reports even at identical risk per dog. Freeze-dried was not a category in the FDA's data at all. Absence of reports is not evidence of absence.

What we can say is narrow and true: the ingredient most consistently present in the reported diets is not in ours.

What to do if you are worried

Talk to your vet rather than switching food because of a headline. Be extra proactive if your dog is a Golden Retriever, or a breed already prone to heart disease like a Dobermann or Great Dane. Ask for a heart check at your next visit. If anything looks off, ask about an echocardiogram. It is the only way to see how the heart muscle is really working.

And if your dog is currently well on a food that contains pulses, that is a conversation to have calmly with your vet, not an emergency.