We’ve touched on allergies in other articles, but let’s focus on those related to our dogs’ diets. A food allergy is essentially a health issue where your furry friend’s immune system gets confused and reacts to a component of their food as if it were a threat. This causes an inflammatory response. On the other hand, we have food intolerances or sensitivities, which occur when your pal’s digestive system has trouble processing something, but their immune system isn’t involved.

Let’s look at an example to understand it better:

Imagine your companion regularly eats chicken. At first, their body assimilates it without any problems. But over time, their immune system may begin to identify the proteins in chicken as something foreign or alien. This is the beginning of sensitization.

Then, that immune system, whose job is to protect them from agents like viruses and bacteria, mistakenly interprets the chicken protein and considers it an invader. An incorrect immune response occurs.

To “defend” itself from that protein that it now considers harmful, your friend’s body begins to produce specific antibodies against it. These antibodies are ready to act if the protein enters again.

The next time your companion eats chicken, those antibodies recognize the protein and trigger a response. This reaction releases chemicals (like histamine) that cause inflammation, and that’s when the symptoms that worry us appear: itching, skin problems, digestive disorders… That is the allergic reaction.

Now, sometimes, as we mentioned, the problem isn’t an immune response. Simply put, their body has trouble digesting certain components. This may be due to a lack of the enzymes needed to break them down properly, or to some intestinal irritation. This can also cause digestive symptoms, and in that case, we’re talking about a food sensitivity or intolerance.

It’s important to know that this disproportionate defense mechanism doesn’t appear overnight. That’s why a dog may have tolerated certain foods for years without apparent problems, and suddenly develop an allergy. This occurs due to continuous exposure to that component that their body now identifies as an allergen.

What Components Usually Cause Food Allergies and Intolerances?

Allergic reactions in our dogs are usually caused by common ingredients in their diet. Since sensitization occurs through repeated ingestion, it’s not surprising that the most common foods in their diet are the ones that most frequently cause reactions. The most common ingredients are:

• Animal-based proteins: Chicken, beef, pork, lamb, and fish are the main suspects. Dairy products, such as milk or cheese, can also be problematic for some companions.
• Gluten-containing grains: Wheat is the most flagged, but corn and soy can also cause sensitivity or reactions in some dogs.
• Food additives: Artificial flavors, preservatives, and other low-cost additives used in some pet foods can also be triggers.
• Other plant-based ingredients: Although less common, some dogs may develop an allergy to vegetables such as soy, peas, or carrots present in their food.

Hypoallergenic Feeds: A Valuable Alternative

The good news is that there are solutions! Hypoallergenic feed is a food specifically formulated to minimize the risk of reactions in dogs with allergies or intolerances. They are highly recommended because they offer an adequate, safe, and nutritionally complete diet for companions with sensitivities. What distinguishes them?

• Limited and selected ingredients: Hypoallergenic feeds usually have a reduced composition, with ingredients carefully chosen to avoid the most allergenic substances. This also facilitates the identification of possible allergens.
• Novel protein sources: They use less common proteins (such as insects, kangaroo, ostrich, horse…). Being infrequent in the usual diet, the probability of reaction is lower.
• Hydrolyzed proteins: Some formulas use proteins that have been fragmented (“hydrolyzed”) into particles so small that the immune system has a harder time recognizing them as a threat. It is a very useful option in cases of more severe allergy.
• No artificial additives: They are free of artificial preservatives, colorings, or flavorings that could cause problems.
• Selected carbohydrates: They opt for sources like pumpkin, parsnip, or sweet potato, which are usually better tolerated by sensitive digestive systems.

Why Are They So Recommended?

• They control allergies: They are an effective tool for managing the symptoms of food allergies and are essential in exclusion diets for diagnosing food allergies in dogs and cats.
• They contribute to long-term health: By avoiding exposure to allergens, they help improve the dog’s overall condition and can reduce visits to the vet.
• Balanced nutrition: Despite their limited composition, they are formulated to ensure that your companion receives all the essential nutrients for their health.

And How Does Food Allergy Arise in Dogs?

Understanding the origin of food intolerance in dogs is a bit more complex, but it relates to the way the dog’s body processes food.

Of course, each companion is a world, and not everyone reacts the same way to the same factors or presents the same signs of allergy. Genetic predisposition is certainly important; it is well known that certain breeds of dogs, such as French Bulldogs, West Highland White Terriers, Boxers, Golden Retrievers, Cocker Spaniels that we mentioned, have a greater risk of developing allergies or are more prone to food allergies. However, genetics aren’t everything. Age also influences; although an allergy can appear at any time in your friend’s life, the development and maturity of their immune system in the early stages is crucial.

Now, these predisposing factors need a key trigger to act: repeated exposure to the potential allergen. Without that continuous and prolonged contact with the protein in question, the allergic sensitization process hardly begins. It is this constant exposure that allows the immune system to ‘learn’ to react.

Digestive or enzymatic problems are also determining factors. Some dogs may have deficiencies in certain enzymes necessary to properly break down certain components, which makes their digestion difficult and causes a sensitivity response. On the other hand, there is the intestinal barrier: if it is weakened, it can allow the passage of undigested proteins that activate the immune system. But the role of the intestinal microbiome is also vital, that community of beneficial bacteria that lives in their intestine. A balanced microbiome helps “educate” the immune system to tolerate foods correctly.

The state of the intestine is another crucial factor. Alterations in the intestinal microbiota (the beneficial bacteria) or an irritable bowel can affect the dog’s ability to tolerate certain ingredients. An imbalance in this microbiota can cause unexpected reactions. Thus, factors such as a monotonous diet, the use of antibiotics or even stress can unbalance this microbiome (dysbiosis), making your companion more prone to developing sensitivities and suffering allergies. Even what they ate in their early stages of life, including their mother’s diet if they were breastfeeding, can modulate how their immune system will respond to food later.

How Can We Confirm if it is a Food Allergy or Sensitivity?

To diagnose a food allergy or intolerance, it is essential to have professional help. The veterinarian has several allergy tests and diagnostic methods for dogs with sensitivities:

• Elimination diet: It is one of the most reliable methods. It consists of offering the dog a diet with ingredients that they have not consumed before (or a specific hypoallergenic diet for dogs) for a period of 8 to 12 weeks. If the dog’s symptoms improve or disappear, it is a clear sign. Subsequently, the suspected foods are reintroduced one by one to identify which triggers the reaction.
• Provocation tests: After the elimination diet, the suspected food is reintroduced to confirm whether the symptoms of food allergy reappear. It helps to point out the responsible allergen.
• Blood tests (IgE tests): There are tests that measure certain antibodies (IgE) in the blood associated with allergic reactions. However, their reliability can be variable, so their usefulness should be assessed by the veterinarian.

• Observation and record: It is very useful to keep a detailed record of everything your dog eats (including treats and extras) and note any symptoms you observe. This helps to detect patterns and identify possible problematic foods.

With these methods, the veterinarian can reach a clear diagnosis and help you establish the most appropriate feeding plan for your companion to feel well and enjoy a good quality of life.

Conclusion: Food Allergies and Intolerance in Dogs

After analyzing this important topic, it is good to have some clear ideas for the well-being of your companion. As we have seen, understanding why food sometimes doesn’t sit well with them can be complex. The key thing is to remember that key difference: food allergies are an immune system response, while food intolerance is a digestive matter. And it is interesting to know that it can manifest suddenly, even with habitual foods.

So how do you know what is affecting your friend? It requires patience and, fundamentally, the guidance of the veterinarian. Elimination diets are the safest tool to accurately identify which ingredient is causing problems. Identifying the responsible party is the decisive step to be able to help them effectively when suspecting allergies.

And once you have identified what to avoid, hypoallergenic feeds become excellent allies. With their special formulations, they are a very valuable solution not only to control the symptoms that worry you, but as part of a long-term care strategy and test to diagnose food allergies. This ensures that your faithful friend receives adequate nutrition to stay healthy and happy, enjoying their meals without problems. Because even if you sometimes cling to ‘old habits’, the best habit you can have with your dog is to observe their needs, listen to the experts and be willing to adjust their diet to ensure their well-being.

Frequently Asked Questions

If my dog is allergic to chicken, should I also worry about other derived products such as feathers (in toys or duvets) or even vaccines that may contain traces?

It’s a reasonable question, but generally, food allergy is triggered by ingesting the protein. The reaction through contact with feathers is very unlikely in a strictly food allergy (it would be more typical of an environmental or contact allergy). Regarding vaccines, although some may contain proteins (such as egg), it is extremely rare for them to cause an allergic reaction related to a pre-existing food allergy.

However, if your dog has a history of severe allergic reactions or multiple allergies, it is always prudent to inform the veterinarian about their specific food allergy before administering any vaccine or new treatment, so that they can assess any potential risk, however minimal it may be.

The article mentions gluten-containing grains in the diet as problematic ingredients, but also corn and soy. Is the reaction always specifically to gluten, or can my companion develop allergies to wheat, corn or soy for other reasons, even if it’s not the gluten?

Although we sometimes talk generically about “gluten allergy,” the reality in dogs is usually more of a wheat allergy in itself, where they react to various proteins of the grain, not exclusively to gluten. On the other hand, reactions to corn and soy are definitely not due to gluten (these cereals do not contain it in the same way as wheat), but to their own specific proteins, which are also fairly common potential allergens. Therefore, many hypoallergenic diets avoid these three ingredients (wheat, corn, soy), not only because of gluten, but because each can be a trigger on its own.

Most hypoallergenic feeds are designed precisely to avoid the most common ingredients that cause problems. So, if you suspect that gluten or wheat makes your companion feel bad, a hypoallergenic feed (always chosen with the help of your veterinarian, of course) is one of the safest and most effective options you can consider for them.

The article explains very well what characteristics define a hypoallergenic feed, but when we find so many options on the market, is there any quality seal or official certification that helps us safely identify that a feed really meets those criteria against intolerance or food allergy in dogs?

There is no single official seal, nor a standard and universally recognized certification that says “Hypoallergenic Certified” on dog food, as there is, for example, for “organic” products. The term “hypoallergenic” is rather a description used by the manufacturer to indicate that the formula is designed to minimize the risk of allergies.

There is no independent entity that audits and seals all feeds under a single “hypoallergenic” standard.So how to choose? Instead of looking for a specific seal that doesn’t exist, it is more useful to look at the list of ingredients as we mentioned earlier, the reputation of the brand, the recommendation of your veterinarian and that it is a complete and balanced food according to nutritional statements such as those of AAFCO or FEDIAF.