By Alexis Weisend, The Seattle Times
A proposed class-action lawsuit claims that Costco falsely advertised its Kirkland Signature Nature’s Domain grain-free dog food as healthy while hiding that it could cause heart disease.
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In a lawsuit filed Tuesday in the federal court for the Western District of Washington, California resident Taylor West claims he purchased the grain-free dog food for his dogs because Costco advertised it as a healthy choice.
He discovered, however, that the dog food, in addition to other grain-free brands, has been associated with dilated cardiomyopathy in dogs, and that there is “no medical or scientific justification to feed a dog a grain-free diet high in legume or pulse ingredients,” his attorneys wrote in the complaint.
Four different law firms, including Seattle-based Tousley Brain Stephens, represent West in the lawsuit.
The product packaging markets Nature’s Domain grain-free dog food as “formulated to meet the nutritional needs” of dogs and says it provides “great nutrition for overall health and vitality of all dogs,” according to the claim.
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The lawsuit points to studies that show a link to possibly fatal heart disease and a 2019 Food and Drug Administration investigation of 16 brands of dog food may be associated with a heightened risk of heart failure in dogs, including Nature’s Domain.
In 2022, the FDA announced it had paused the investigation “until there is meaningful new scientific information to share.” The agency encouraged continued “research and collaboration by academia, veterinarians, and the industry.” But West’s attorneys claim many veterinarians still advise dog owners against feeding their dogs grain-free dog food.
The attorneys want to open the lawsuit to all those who purchased Costco’s grain-free dog food in the last four years and seek damages for West and other potential class members.
Costco did not immediately respond to a request for comment.
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