As cats are carnivorous, wheat is not a food that they would choose to eat in the wild, however, it is used in one form or another in many cat foods and treats. Some cats develop an allergy to wheat or the gluten protein that it contains. Cats with food allergies often develop unsightly and uncomfortable skin conditions. An elimination diet may be required in order to accurately identify the allergen that is affecting your feline. This process may be time-consuming but is the most popular and accurate method currently available to deduce which ingredient is causing the patient’s reaction.

An allergy to wheat is caused by an over-reaction of your cat's immune system to an unwelcome protein that is present in the wheat itself.

Symptoms of a food intolerance often precede or accompany a full-blown allergic attack to the particular ingredient. Intolerance to food generally presents as abdominal pain, digestive distress, and gurgling sounds from the digestive system. Symptoms of food allergies typically originate on the head and neck on felines and can include signs such as:

A food allergy, such as an allergy to wheat, is the response a cat’s immune system employs to defend itself against a protein that it has identified a threat. An allergic reaction doesn’t happen the first time an animal is exposed to the allergen, only after repeated exposures. Any food is capable of triggering an allergic reaction, but some foods, such as wheat, corn, seafood, beef, and dairy products, are more likely to elicit a response. 

While allergies to foods like wheat are the immune system’s response to what it recognizes as a threat, food intolerance has no immune involvement. Food intolerances are also much more likely to cause a digestive reaction than allergies are. Additional symptoms, such as a change in the consistency or color of the stools and gastrointestinal gurgling sounds are commonplace when dealing with a food intolerance, but less frequent for allergies.

Allergies, including allergies to food items, are due to an abnormally intense defensive response to the protein in the wheat, which the immune system has identified as an invasive substance. Approximately 60-70% of the cells that make up our immune system actually reside in the gastrointestinal tract, and the same applies to our felines. Digestion, as a process, is designed to break down foods into their smallest possible parts, known as amino acids. These amino acids are then absorbed by a specialized type of white blood cell called an enterocyte which then transports the amino acid into the bloodstream. 

When proteins are incompletely broken down, the enterocytes identify any oversized fragments of food, in this case, fragments of wheat protein, or gluten, as dangerous intruders rather than essential nutrients, and they attack. When exposures to the protein are repeated, the reactions of these cells becomes increasingly aggressive, and allergy symptoms intensify. 

Although it is possible for allergies to develop to any food, some foods are more likely to generate a reaction than others. The most familiar triggers for feline food allergies can include:

Allergy symptoms in felines closely mimic other skin disorders such as bacterial skin infections, mites, and fungal infestations, leading many veterinarians to collect samples of the skin to be examined under a microscope using a process known as cutaneous cytology. Allergies are likely to be suspected where there are no problematic micro-organisms found. Although both intradermal and serum testing are available for felines that are afflicted with allergies, they are not typically considered reliable for detecting food allergies. The gold standard for the veterinary diagnosis of allergies that are triggered by food is the elimination diet. In order to implement an elimination diet, the cat’s daily diet is changed to either a specialized hypoallergenic or limited ingredient commercial cat food, or in some situations, to a diet of cooked and unseasoned human food. 

An elimination diet for your allergic cat has a much greater chance of success if novel ingredients are used in place of the cat’s current food. Novel ingredients can be defined as any proteins or carbohydrates that are not currently part of the cat’s current food and preferably ingredients that the animal has never been introduced to. It is crucial to check all of the ingredients in commercially prepared recipes if you suspect a wheat or gluten related allergy as wheat and gluten are often added to food as a filler and may not be listed specifically as wheat. Gluten is also commonly identified on ingredient labels as hydrolyzed vegetable protein, modified food starch, or even as vegetable gum. Once the symptoms of the allergy are completely under control, new ingredients can be reintroduced into the cat’s diet one at a time.

It may require several weeks on the elimination diet to reveal which particular ingredient is causing the distress, and during this time your cat may continue to experience residual symptoms of the allergy. Antihistamines are frequently recommended in order to calm itching and scratching and corticosteroids are often an effective way to reduce swelling. Both of these treatments may make it more challenging to uncover which ingredient in your cat’s daily diet is triggering the reactions by masking the symptoms of the allergy. Due to this tendency, many veterinary professionals will delay the prescription of these types of medication until they are able to administer the elimination diet.

Cats that are experiencing allergic reactions that affect the skin frequently develop secondary skin infections and antibiotics are usually prescribed to combat and prevent this complication, and once the specific allergen has been identified, it should be eliminated entirely from the cat’s diet, and an allergy to gluten may mean eliminating not just wheat, but other grains such as barley and oats. Additional daily supplements, including probiotics and Omega-3 oils, are frequently recommended for all sorts of allergies in order to support the immune system in order to help your cat’s body to handle any accidental exposure to the proteins in wheat as well as helping to prevent the cultivation of new allergies.

Although allergies to foods are not curable, the symptoms are typically dispelled if the allergen is removed from the animal’s diet. Subsequent exposures of even small amounts of the allergen may cause a relapse, so caution must be maintained regarding the type of treats and flavorings you use for your cat. Unfortunately, if your feline has had an allergic response to one ingredient, they are more likely to eventually develop new allergies to the ingredients in the replacement diet. Veterinary professionals are split on their approach to combat this situation, with some doctors promoting a single source of food unless new symptoms develop, and others maintaining that a steady rotation of a few novel protein foods is more beneficial.