Dog Food Allergies vs Food Intolerance: What’s the Difference?

If your dog experiences itchy skin, ear infections, or stomach upset, you might suspect they have a food allergy. However, before you assume your pet’s symptoms are food allergy-related, it’s important to learn more about what an allergy really is and how it affects your pet.

Dr. Danielle Opetz, Fromm’s Doctor of Companion Animal Nutrition, helps us understand some of the differences between true food allergies and food intolerance in this article, beginning with some common misconceptions about both.

Dog Food Allergies: Myths & Misconceptions

Food allergies can be frustrating for both you and your dog. Sometimes itchy skin or digestive upset are due to a different type of allergy—or, not due to allergies at all!

Today, we’re going to review three common myths about dog food allergies.

MYTH #1: Food Allergies Are Very Common In Dogs

Food allergies aren’t nearly as common in pets as many people believe them to be. Symptoms of allergies (most commonly, itchy skin, skin and ear infections, and digestive issues such as diarrhea) can be caused by many different conditions that may have nothing to do with allergies. For example, skin mites or hormonal conditions can cause skin problems and intestinal parasites or dietary indiscretion (like eating something off the ground during a walk) can cause stomach upset.

So, if your dog shows these symptoms, your veterinarian may test for more common conditions first. Then, even if it’s suspected your pet has allergies, there are different types of pet allergies, including:

• Flea bite/flea saliva

• Environmental allergies (inhaled allergens like pollen, dust, smoke, etc.)

• Food allergies

Dogs may have just one type of allergy, or more than one type, but food allergies account for only 10% of pets with allergies!

No matter what’s causing your dog's symptoms, it’s important to figure out the root cause, so your dog can receive an appropriate treatment.

MYTH #2: Allergy Tests Will Tell Me What My Dog Is Allergic To

Of the dogs that do have food allergies, the most common allergens are proteins, including those from chicken, beef, eggs, dairy, lamb, soy, or wheat. But, pets may be allergic to any food ingredient—so it’s important to find a diet they do well with.

While a blood test for allergies may provide some information, it’s generally not an accurate way to test for food allergies (it’s better for environmental allergies). Often, these tests show pets as allergic to an ingredient that is really okay for them, making it confusing to choose an appropriate diet.

A food trial, also known as an elimination diet trial, is the best way to test for food allergies. However, a food trial takes discipline and patience. A food trial means your dog can eat ONLY a specific type of food for at least a month (sometimes as long as 2-3 months). Other treats, table scraps, and even flavored medications aren’t allowed, because they can interfere with the food trial results.

MYTH #3: My Dog Has Symptoms While Eating Certain Foods Or Ingredients—That Means They Have a Food Allergy, Right?

If your dog has physical symptoms in response to certain foods, it’s possible they have a food allergy. But, it’s also possible they have a “food intolerance.”

What’s the Difference Between a Food Allergy & Food Intolerance?

An allergy is when your pet’s immune system is involved. The body misinterprets the ingredient as an “intruder” (as if it were a virus or bacteria), and the immune system begins to attack it. The side effects of this immune response are inflammation and the symptoms of allergies.

A food intolerance, on the other hand, does not involve the immune system. It’s when the body just doesn’t process or digest an ingredient very well, leading to vomiting, diarrhea, or other symptoms. A food intolerance is a very important consideration for your pet’s health, since it can cause unpleasant physical symptoms. However, with a food intolerance, your pet may have more dietary options than a pet with true food allergies.

Many pet parents who suspect their pet has an allergy to a specific ingredient are surprised to see their dog does will on a Fromm dog food diet—even if that recipe contains the suspected allergen! The reason for this is due to what we call the “multi-ingredient principle.”

How Does the Multi-Ingredient Principle help Dogs with Food Intolerances?

Fromm dog foods contain a variety of ingredients, including diverse protein sources, fruits, vegetables, and carbohydrates. In other words, it’s about the total balance of all the components, without too strong of a reliance on any one particular ingredient.

In addition to providing great nutritional balance, this principle may offer a solution to dogs with a dietary intolerance (and not a true allergy). The ingredient in question will be present in a smaller amount—an amount that a pet’s body may tolerate better.

To understand this principle, compare it to a spicy dish for us human beings…With a small amount of spice, the food tastes good, and even a person with a sensitive stomach can enjoy it. Too much spice, on the other hand, can cause an upset stomach.

Food intolerances in pets can follow a similar pattern. So, the multi-ingredient principle provides healthy options that often work wonderfully for pets with sensitive stomachs or food intolerances.

Finding the Right Food for Your Dog

When it comes to food allergies and intolerances in dogs, most experts will tell you there’s no one size fits all. What works very well for one pet might not work for another. Patience is important. You may need to try several diets before you find the right one for your individual dog.

Once you find the food that works well for your pet, the time you put into selecting that food will be worth it. Each time you fill the food dish, you’ll be helping your dog thrive, so they can enjoy their best life without annoying allergy or food intolerance symptoms.

From our family to yours,
Fromm Family Pet Food

Danielle Opetz is the Doctor of Companion Animal Nutrition at Fromm Family Foods. She earned her Ph.D. in Nutritional Sciences from the University of Illinois Urbana-Champaign in 2023. She also holds a bachelor’s degree in zoology/animal biology from the University of Wisconsin-Platteville, as well as a master’s degree in animal sciences with an emphasis on companion animal nutrition from the University of North Carolina at Chapel Hill.