Pets and Food Allergies

By Dr. Avi Deshkmuth, DVM, MS, Ph.D

What Is Food Allergy?

A food allergy is an adverse immune response to a food protein, triggered by the body’s immune system. Some proteins are resistant to digestion and those that are not broken down in the digestive process are attached to the Immunoglobulin E (IgE). The immune system mistakenly thinks that the food particle is harmful, thus triggers an allergic reaction. The most common signs of a food allergy:

1. Dermatologic (skin) reactions such as: Itching (pruritus), Bumps (papules), Redness (erythema).
2. Gastrointestinal (GI) signs such as vomiting and diarrhea.

What are the most common causes of skin diseases?

Studies suggest that skin disease accounts for as much as 25% of the canine cases presented to veterinarians.  The underlying causes for skin disease can vary greatly by region or time of year. The graph below gives the results of one study. 

Which ingredients in pet foods are most allergic?

The veterinary literature does not say which protein sources cause most food allergies.  However, incidence of grain based food allergies, due to corn and wheat, is less than 5% 

How many protein sources are present in grain-free pet foods?

Anywhere between 5 – 15.  The most common protein sources in grain-free pet foods are chicken, beef, lamb, fish, turkey, venison, potatoes, natural flavors and vegetable sources.

The study shows that about 87.8 % of the skin cases are due to Flea allergy (50.2%) and environmental elements (37.6%). Less than 1% skin cases are due to “True food allergy”.  Thus, the incidence of true food allergy is very, very low. Diagnosis of food allergy:

Blood tests to diagnose food allergy are totally unreliable. “Diet Elimination Trial” is the GOLD STANDARD to confirm food allergy diagnosis.

• Carefully designed single protein source exclusion diet based on dietary history
• Duration ~12 weeks
• To confirm, re-challenge and symptoms should reappear.

Will grain-free pet foods prevent or cure food allergies?

Not necessarily. The animal could be allergic to any of the protein sources in grain-free pet foods.

Pet owners should remember that the only way to determine a food allergy is through Diet Elimination Trial, and should not automatically assume it is a grain allergy.  Research confirms that 87.8% of skin allergies are flea and environment associated, and less than 1% of skin cases are true food allergies.