Why do some dogs develop food allergies?

Allergies affect many dogs in the UK, with food allergies being a common but often misunderstood type. This article explores why dogs develop food allergies, what triggers them, and how symptoms may arise at any age.

The importance of allergen identification

Managing a dog’s allergies effectively begins with identifying the exact allergen. Food allergies require discovering the specific ingredient your dog reacts to so it can be removed from their diet. Without pinpointing the allergen, treatment efforts are often reactive and only partially successful. Some dogs have subtle symptoms, making it challenging to suspect food allergies early on.

Why food allergies can be so challenging

While allergens like pollen are difficult to avoid, theoretically, food allergies should be simpler to manage because you can switch to foods without the problematic ingredients. However, mild or invisible reactions such as loose stools or slight discomfort often go unnoticed. Unlike hereditary atopic allergies that tend to run in breeds, food allergies can appear in any dog regardless of breed or family history and may develop suddenly later in life.

Why do food allergies develop?

Food allergies in dogs occur due to an immune system overreaction to certain dietary ingredients, primarily proteins such as chicken, beef, dairy, eggs, wheat, and soy. The immune system mistakenly treats these as threats, producing antibodies which trigger allergic responses. This usually emerges after repeated or prolonged exposure to the allergen, explaining why dogs may tolerate a food for years before symptoms appear.

Genetic predisposition plays a role, with breeds like Labrador Retriever puppies, West Highland White Terriers, Boxers, and Cocker Spaniels more susceptible to food allergies. However, food allergies can affect any breed.

Certain ingredients such as wheat are common culprits as they offer no nutritional benefit and are unusual in a dog’s natural diet. High-protein foods uncommon in the wild, like shellfish and beef, also frequently cause allergies.

Another theory suggests that repeated intestinal worm infestations may reduce tolerance to allergens, turning harmless ingredients into triggers for allergic reactions. Keeping a rigorous worming schedule is important not only for general health but may also help reduce allergy risk.

Food allergies versus food intolerances

It is important to distinguish between food allergies and food intolerances. Allergies involve the immune system and cause reactions upon exposure even to small amounts of the allergen. Intolerances do not involve the immune system and typically only cause issues if large amounts of the offending food are consumed. Understanding the difference helps in diagnosis and treatment planning.

Recognising symptoms and next steps

Food allergies may manifest as skin problems, itching, digestive upset, or ear infections. If your dog shows signs of discomfort or changes in health after eating, consult your vet for diagnosis. An elimination diet followed by gradual reintroduction can help identify triggers.

Responsible pet ownership includes sourcing food from reputable suppliers and maintaining regular health checks, including worming.

Learning about the causes and management of food allergies empowers you to provide the best care for your dog, improving their comfort and wellbeing throughout their life.