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Questions and Answers about Food Allergies in Dogs and Cats

Author Bruce Novotny, DVM
Editor Lisa Freeman, DVM, PhD, Diplomate, ACVN

How common are food allergies?

No one knows for sure how many pets have food allergies, but several numbers are frequently cited in the veterinary literature. Veterinary dermatologists suggest that adverse food reactions account for 1% to 6% of all dermatoses (skin diseases) in general practice and that food is the cause of 10% to 20% of allergic responses in dogs and cats. Food allergy is probably the third most common hypersensitivity skin disease in dogs and cats after flea allergy and atopy.

Food allergies affect the gastrointestinal tract, but we do not know how often. Food sensitivity probably is involved in some cases of the two most common causes of inflammatory bowel disease and chronic vomiting and diarrhea in cats and dogs—lymphoplasmacytic enteritis and eosinophilic enteritis.

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What proteins most frequently cause food allergies?

Ten scientific studies have shown that certain proteins in beef, dairy products and wheat account for two-thirds of the reported cases of cutaneous food allergy in dogs.
Beef, dairy products or fish account for almost 90% of the reported cases of cutaneous food allergy in cats. The veterinary literature does not say which proteins are most commonly involved in GI food allergies.