Grain free diets became wildly popular in the early 2000s but have been causally linked with a serious heart condition called Dilated Cardiomyopathy in dogs. Pet food marketing agencies began encouraging owners to switch to grain free because they led people to believe the absence of grains were healthier for their pets. Some pet owners also believed that grains were related to allergies and gastrointestinal upset. Veterinary dermatologists have determined that the main protein used in dog food is much more likely to cause food allergies, and that allergies related to grains are extremely uncommon in dogs and cats. When veterinary cardiologists noticed an increase in DCM in dogs they considered of the association with grain free dog foods. The FDA has confirmed that grain free diets are linked to non-hereditary DCM which is a serious condition that can lead to heart failure and death. Researchers are working to find the exact mechanism that causes this disease but it is now believed that legumes interfere with the absorption of Taurine, an essential amino acid. The FDA and veterinary cardiologists recommendation is to transition off of grain free diets and boutique diets to a diet with grains included. Pet nutrition is not one size fits all so it is recommended to speak with your veterinarian or a veterinary nutritionist to get the best advice for your pet.