Where grain free dog food might be all the rage as it turns out it may not be as good as we think. It can cause heart problems for both dogs and cats. Heed this warning from this veterinarian as well as the FDA. Keep in mind that the study is still being conducted but why take the chance. If You are feeding that fur family member "Grain Free" with items like Sweet Potatoes, Lentils or Peas included it is important to be aware. Some of the brands identified include Acana, Zignature, Taste Of The Wild as well as 4Health.