The Family Pet by Dr. Michael Trapani — March 2020

The greatest talent of human beings is our ability to know things without really knowing. We are adept at making conclusions from inadequate data. It works! Except when it doesn’t. Our "gift" generates both deep insight and incredible stupidity. Ain’t bein’ human grand?

I am an Evidence-Based Practitioner. I don’t claim to KNOW anything. Instead, I develop my best understanding of available evidence. When new information turns up, I revise my thinking.

Let’s face it, we humans have believed lots of things that were later proven to be untrue. No matter how much we know, there’s always more to learn and better understanding for us to develop.

Today, I’m offering up an idea that I cannot prove, I have little evidence to support, and that may prove to be untrue. In a universe full of uncertainty, it must be accepted that even the most cautious of us will make mistakes. We WILL, sometimes, draw incorrect conclusions. We are human. It’s our nature to screw up.

Knowing that we make mistakes, it is incumbent upon us to make the SAFEST MISTAKE possible: one that harms the least number and generates the greatest benefit.

We have all seen news stories about grain-free diets causing Dilated Cardiomyopathy (AKA "DCM") in dogs. Oh, the incidence is low, and the proof is sparse, but there is definitely something going on and way too many previously healthy dogs are turning up with this condition after being fed boutique or grain-free diets. Many of these dogs die. Some evidence suggests that low dietary taurine levels (an amino acid found in meat) promote the problem. Hearts starved of taurine develop weak muscle strength and loss of cardiac function, causing heart failure and death. Some of these dogs have low blood taurine levels. Some of them normalize when placed on higher taurine diets. Others do not show these test results and do not improve with taurine.

OK. You waited for it: I think I’m seeing this disease in CATS. I can’t prove it.

Way back in the 1980s, we used to see dilated cardiomyopathy (DCM) in cats. The disease was almost uniformly fatal. The cats would be fine, then go into heart failure, seemingly out of the blue. Treatment did little good and most of them died soon after onset of the disease. THEN, by the mid-1980s, the link between dietary taurine levels and DCM was discovered. Commercial diet formulations were adjusted and DCM in cats quickly disappeared. Decades passed with no cases. Feline taurine deficiency became a thing of the past.

Recently, DCM cases in dogs associated with legume and pea based (grain-free) diets have spiked, generating great concern. Cats are eating these diets too!

I have seen several cats with DCM recently: Two came from the same household and died within hours of presentation, so rapidly that there is no way to be sure of the cause. A third cat in the same household, who refused to eat the grain-free food, remained healthy. Another cat developed DCM signs, including low-protein fluid in the chest cavity, and appears to have returned to normal with dietary changes and taurine supplements.

The last cat was referred to a cardiologist, was medicated for DCM, placed on taurine supplements, and has improved. Only this cat has been tested, and his blood taurine level was normal. Whether his heart function will return completely to normal on taurine remains to be seen.

So, I’m not sure: Has taurine deficiency-induced DCM in cats returned because of grain-free diets? Or am I drawing imaginary conclusions based on insufficient evidence? What is the Safe Mistake?

I feed my own cats a variety of diets and change the ration regularly. I never trust anyone diet to provide for all of their needs and feed them many different foods. There is no completely perfect diet. If your cat has no specific, special needs, feed a variety of quality diets and let those diets correct each other’s flaws.

Maybe I’m right and maybe I’m not. Millions of dollars and years of research will be required to sort all of this out. Until that happens, make the safe mistake: Don’t feed ONLY grain-free diets!

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