Food allergies in dogs are an immune response that can cause skin issues or gastrointestinal discomfort for your pet. Keep reading to learn about the types of food allergies in dogs, common triggers, and how to manage them.
What are food allergies in dogs?
A food allergy is an overreaction of the immune system that occurs when a dog is exposed to a certain ingredient that triggers an allergic response.
A food allergy occurs when a dog’s immune system recognizes a certain portion of food, usually a protein, as a foreign invader. The immune system, which is normally responsible for fighting off harmful pathogens, then mounts a response to attack what it perceives as foreign. This leads to the symptoms we see in dogs, typically itching and gastrointestinal signs.
With food allergies, it’s common for a dog to be able to eat the offending food for months or even years before symptoms start to show.
Any dog can develop a food allergy, although some breeds are more likely to be affected, including Labrador Retrievers, Cocker Spaniels, and West Highland White Terriers.
What is the most common food allergy in dogs?
Proteins are the most common type of trigger for food allergies. According to Embark data, 5.3% of dogs have a food allergy. Of those dogs, 60.6% are allergic to an animal protein and 22.4% are allergic to a grain.
What allergens can trigger food allergies in dogs?
A review of several studies determined that the most common ingredients responsible for food allergies in the studied dogs were beef, dairy, chicken, and lamb. Wheat, soy, and corn were the most common plant-based ingredients implicated in food allergies; however, allergies to these three ingredients were less prevalent than the four common animal protein-based allergies. Occasionally, a dog will develop an allergy to a preservative or a filler in their food.
Remember that a recent diet change is not necessary for a food allergy to develop. Food allergies require a dog to be exposed to the allergen first, and it takes time for them to develop an overzealous immune response to their food. That means that they typically have been eating the offending ingredient for a long period of time before symptoms develop.
What are the signs of food allergies in dogs?
Common signs of food allergies include:
- Itchy skin that does not wax and wane with seasons
- Frequent and recurrent ear or skin infections
- Licking/chewing feet or anus
- Diarrhea
- Vomiting
- Weight loss
How does a veterinarian diagnose a food allergy?
Unfortunately, there isn’t an easy test veterinarians can use to diagnose food allergies at this time. Although blood, saliva, and skin tests that claim to diagnose allergies are available online, they generally aren’t reliable or recommended by veterinarians for food allergies.
If you suspect your dog might have a food allergy, your veterinarian may discuss performing a strict food trial, which is currently the only reliable way to diagnose a food allergy. That means your dog will eat their trial diet (usually a prescription diet) only for at least eight weeks. Your dog should not eat any other food during this period—that means no treats or people food!
Remember that a food elimination trial is a diagnostic procedure, not just a new diet. It should only be performed under a veterinarian’s supervision.
If your dog is diagnosed with a food allergy, your veterinarian might recommend a specific diet or type of dog food to avoid the allergen.
Can food allergies be prevented or treated?
The best treatment for food allergies is to avoid the offending allergen. This usually means keeping the dog on a limited ingredient or hydrolyzed diet. Hydrolyzed diets typically use ingredients that can cause food allergies (such as chicken or beef), but these ingredients are broken down into tiny molecules so the immune system won’t recognize them as foreign. These diets are available through a prescription from your veterinarian.
Food allergies vs. food intolerances
When discussing dietary issues in dogs, people commonly interchange food allergies and food intolerances. However, there are some key differences between these two reactions.
While food allergies are triggered by an abnormal immune response, food intolerances do not involve the immune system. Another key difference is that dogs can show intolerance to a food or ingredient the first time they eat it, whereas they need at least one prior exposure to a food to develop a true food allergy. Food intolerances typically result in gastrointestinal signs such as vomiting or diarrhea.
Common food intolerances could include eating:
- Too much of one nutrient
- A diet with too much fat
- A poisonous or irritating food, like chocolate or rhubarb
- Foods with additives
- Foods with lactose
How to help your dog cope with food allergies
With food allergies, the goal is to avoid the trigger foods in the first place. Recognizing and managing allergen exposure will provide dogs with food allergies the best quality of life.
Learn more about the different types of allergies in dogs and what signs to look for.
