Dog food types
What is DCM and why is it mentioned with grain free diets?
Last updated 23 September 2026 · How we write and check this
Short answer
DCM stands for dilated cardiomyopathy, a disease where the heart muscle weakens and its chambers enlarge, reducing pumping efficiency. It is mentioned alongside grain free diets because health authorities noticed an unusual rise in cases among breeds not typically prone to it, many of which were eating grain free, legume-heavy formulas.
What DCM does to the heart
In dogs with DCM, the heart's main pumping chamber stretches and its walls thin, which over time can lead to reduced exercise tolerance, coughing, fluid buildup, and in advanced cases, congestive heart failure.
Why grain free entered the picture
Breeds like Golden Retrievers, which are not among the traditionally genetically predisposed breeds for DCM, began showing up in case reports starting around 2018, and a notable pattern emerged of these dogs eating grain free diets high in peas or lentils.
The current understanding, still incomplete
Researchers suspect the connection may involve reduced taurine availability or absorption in some of these formulas, but this has not been proven as the sole mechanism, and the investigation into which specific ingredients or combinations are responsible continues.
Key takeaways
- DCM is a heart muscle disease that weakens the heart's pumping ability over time.
- An unusual rise in cases among non-predisposed breeds eating grain free, legume-heavy diets prompted the FDA investigation.
- The exact mechanism remains under study, with taurine availability one leading area of interest.