What causes a food allergy in a cat?
Food allergies in cats are caused a reaction to one or more ingredients in the cat’s food. The most common allergens are fish, beef, eggs, wheat and milk. Although allergies frequently occur when the cat is two to six years old, they can pop up at anytime in a cat’s life, because they can become allergic to foods they have eaten for a long period of time; in fact, allergies build up and can worsen over time.
It’s important to know the difference between food allergy and food intolerance, because they can both create uncomfortable symptoms. An allergy is an immune reaction, usually causing the release of histamines—and that creates the itchy skin and ears and bald spots. Food intolerance creates no immune system response to the offending food, so that problem occurs in the digestive system; the inability to digest food causes uncomfortable gastrointestinal symptoms. In contrast to a food allergy, a person with food intolerance can typically eat small amounts of the identified food without experiencing symptoms.
It’s important to know that food intolerance can also occur as a result of a recent food change, and it usually is an immediate reaction. Food intolerances are due to either a lack of digestion of an item or a lack of absorption. A food allergy (or hypersensitivity) develops as a result of a longer term exposure to a food, where an immune response has occurred. Food allergies can cause dermatologic or gastrointestinal problems.
If you suspect your cat has a food allergy, the first thing you’ll need to do is to take her to the veterinarian to rule out if it is, indeed, that. This is important because most types of allergies have similar symptoms—red, itchy skin, bald spots, vomiting, scratching, etc. If a food allergy is confirmed, the veterinarian will most likely put her on a hypoallergenic (novel) food diet for 12 weeks and then conduct an elimination challenge to pinpoint the offending ingredient.