HOUSTON — The Food and Drug Administration said the potential link between “grain free” food and canine heart disease is a complex issue that involves other factors.

However, the FDA urged pet owners to watch their pets closely for any sign of health trouble, track what foods their dogs eat and report any pet food complaints.

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At Patti’s Pet Depot in west Houston, every five-pound bag or can of dog food sold gets owner Patti Carter’s paw of approval.

“(My rescued dog) Lily eats Nulo (brand dog food),” she said.

Carter said her dog eats only her store’s specialty: high-quality natural dog food. Often, Lily eats “grain-free.”

“I’ve tried almost every food out there and grain free food is what’s helped my pets the most,” Carter said.

So when names she buys landed on the FDA’s list of brands most frequently named in a potential link between dog deaths and diet, Carter and customer Monica Walker took notice.

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“I’m very concerned now,” Walker said.  “I’m going to be paying even more attention to it because I have even used some of those brands.”

Last July, the FDA began investigating reports that dogs who ate certain “grain free” foods had a canine heart disease called DCM. Other factors including breed and genetic predisposition could also be contribute. 

Sixteen brands were most frequently mentioned in the 500 cases reported, according to the FDA.

“A lot of the foods on that list, they’re good foods,” Carter said. “They’re very high-quality foods. I don’t think that people should panic. I think that grain free foods help a lot of pets out there.”

Carter hopes the FDA investigation pushes pet owners to dig deeper into what their dog eats and how it affects the animal.

“Luckily there are a lot of people out there who do read the ingredient panel (and) who do their research,” Carter said. “They come in (to the store) and they know.”