Dogs can be allergic to a lot of things, like pollen, dust, dirt, or mold. It’s also possible for dogs to be allergic to certain ingredients in their food, just like humans.
Around 10% of all allergy cases in dogs are food allergies, so they’re not as common as environmental allergies, but they’re still something to look out for. And the symptoms of food allergies closely mirror the symptoms of environmental allergies, so it can be tough to tell the two apart based on symptoms alone.
Most of the time, a dog suffering from food allergies can be given a hypoallergenic dog food or a limited-ingredient diet in order to eliminate the symptoms. But how do you know what to purchase? What if your dog is suffering from a food intolerance rather than a food allergy? And why do dog food allergies happen in the first place?
Let’s explore the world of food allergies in dogs and find out what causes them, what you’ll notice if your dog is allergic to an ingredient in their food, and what to feed them in order to solve the problem.
What Causes Food Allergies in Dogs?
Allergic reactions to food are caused by the proteins found in the animal- or plant-based ingredients in pet food. As your dog’s body digests those proteins, they’re broken down into molecules. Your dog’s immune system wrongfully identifies those molecules as a threat — that’s what causes the allergy symptoms you see.
There are a few protein sources that tend to cause dog food allergies more commonly than others. They include:
Notice that some of these sources are animal proteins like beef, chicken, and pork. But others are plant-based sources like wheat and corn. Don’t make the mistake of thinking your dog can only be reacting to an animal-based protein because plant sources can be the culprit as well.
What Are the Symptoms of Food Allergies?
Symptoms of food allergies can appear at any age, although they often manifest in puppies younger than one year of age. Still, it’s entirely possible for a food allergy to a particular ingredient to develop after a dog has eaten a food containing that ingredient for years.
Common Signs of Food Allergies
Symptoms of food allergies in dogs can vary from pet to pet, but the most common symptom is itchy skin, particularly focused around the feet and ears. Due to the scratching that your dog does as a response to this itching, skin and ear infections are common in dogs with food allergies.
Other symptoms of food allergies include:
- Sensitive stomach
- Excessive flatulence
Of course, symptoms like these can also be caused by a variety of other health issues. You’ll probably need a veterinarian’s help to confirm whether or not your dog’s symptoms are a result of an adverse reaction to a protein source in their food.
Food Allergy vs. Food Intolerance
It’s important to realize that a food allergy and a food intolerance are not the same thing. Dogs can experience both, and they can be difficult to tell apart without the insight of a veterinarian.
A food allergy — sometimes called a hypersensitivity — means that your dog’s immune system is reacting to an allergen in the food, and it requires that the dog’s system has previously been exposed to that allergen.
A food intolerance, on the other hand, doesn’t involve the immune system. It can occur on a dog’s very first exposure to an ingredient, and it simply means that a dog has trouble digesting that particular food or ingredient. Dairy is one example, as most adult mammals (with the exception of many humans) can’t digest the whey protein found in dairy foods.
Allergy-Prone Dog Breeds
Any type of dog can suffer from a food allergy. But there are a few breeds that seem to deal with them more than others. They include:
- Cocker Spaniels
- West Highland White Terriers
- German Shepherds
If you’re the owner of one of these breeds, your pup may have to deal with a food allergy at one point or another.
Treating Food Allergies With an Elimination Diet
Your dog has displayed symptoms of a food allergy, and you’ve taken them to the veterinarian to confirm the diagnosis. Now what?
Treating a food allergy involves performing a food trial — sometimes called an elimination diet — using a hypoallergenic dog food or a limited-ingredient diet (a food made with a limited number of ingredients, and usually with a single source of protein, carbohydrates, and fat).
A food trial can be done with what is referred to as a novel protein source, or with something called hydrolyzed protein. There are also prescription diets, which are specially formulated for your dog’s needs and can only be obtained through a veterinarian’s office.
The Treatment Process
Here’s how it works. Your dog will start eating a hypoallergenic dog food that contains a novel protein source. This means your dog has never eaten that type of protein before, making it very unlikely that your pup will experience an allergic reaction to that food.
Examples of typical novel proteins include salmon, venison, duck, or even more exotic options like kangaroo, bison, or pheasant. You might see these dog foods marketed as “limited ingredient dog food” or as a “limited ingredient diet.”
Hypoallergenic dog food will also contain a novel plant-based carbohydrate source since plants also contain protein. Sweet potatoes or peas are two examples typically found in hypoallergenic diets.
A hydrolyzed protein diet involves animal proteins that have been broken down into tiny molecules that your dog’s immune system won’t recognize as allergens. In these diets, starch or brown rice is usually used as the carbohydrate source.
Whether your dog receives a hypoallergenic diet with a novel protein source or hydrolyzed proteins, the process is the same. Once your dog has stopped showing signs of a food allergy — confirming that a food allergy was in fact the cause of the symptoms — you’ll be able to start adding ingredients to Fido’s kibble one at a time to determine exactly what your dog is allergic to.
For instance, you might add a few pieces of chicken or beef, or a sprinkling of wheat, to your pooch’s dry dog food. When symptoms return, you know that you’ve found the precise ingredient that your dog reacts to. By using this process of elimination, you know what ingredient or ingredients your dog should avoid in the future.
That way, you don’t have to worry about every single treat or bite of kibble your dog may eat throughout their life — you know exactly what to avoid, and you can choose a diet that suits their unique needs. This also allows you to switch back to a less limited diet, which will contain a better balance of nutrients due to the wider variety of natural ingredients.
A Note on Grain-Free Diets
Many dogs are allergic to certain grains found in dog food, like soy, corn, or wheat. The answer to these problems is often a grain-free dog food that doesn’t contain these ingredients.
But savvy pet owners know that there has been some controversy over grain-free dog foods, especially after the FDA issued a warning linking grain-free foods to heart disease. It is possible to give your dog a whole-grain food that is still free of wheat and corn, two of the most common plant-based allergens in dog food.
Your best bet is to work closely with your veterinarian when choosing a hypoallergenic dog food so you can make sure you’re giving your pet a safe choice.
Choosing the Best Hypoallergenic Dog Food
There are plenty of hypoallergenic and limited ingredient foods to choose from, and you’ll want to get your veterinarian’s approval before purchasing. It’s also important to note that dog food companies often can’t legally label their product as “hypoallergenic,” since your dog could, theoretically, be allergic to anything. So, you’ll probably see words like “limited ingredient diet” on pet food packaging rather than “hypoallergenic.”
Some of the top-rated, limited-ingredient dog foods include:
- Merrick Limited Ingredient Real Salmon & Chickpeas Recipe. A simple, single-protein formula with no grains or gluten, this diet gives your dog extra nutrition thanks to healthy doses of vitamins, minerals, and amino acids (including Omega–3 and Omega–6 fatty acids for healthy skin and fur). And there’s no artificial colors or preservatives.
- Canidae Pure Real Salmon & Sweet Potato Recipe. This is a good choice for a dog with a sensitive stomach, as it contains a mix of probiotics to aid in healthy and easy digestion.
- Blue Buffalo Basics Duck & Potato. With duck as the main protein source, this is a good choice for dogs triggered by more common allergens like beef, chicken, fish, or lamb. There are no potentially triggering by-products, corn, wheat, soy, artificial flavors, or preservatives.
- Purina Beyond Simply 9 Limited Ingredient Recipe. This all-natural food doesn’t include wheat, corn, soy, or any poultry by-products. The main ingredient is chicken, so it will work for dogs suffering from allergies to other protein sources like beef, pork, or fish. If your dog’s food allergies don’t clear up, you may want to try a chicken-free recipe next.
At the end of the day, your best course of action is to follow the advice of your veterinarian. He or she can help you pick a diet that’s right for your puppy or adult dog’s allergy problems.
Hypoallergenic Dog Food: The Bottom Line
Food allergies in dogs can definitely be a hassle. But you have a secret weapon: Hypoallergenic food options that can help your dog live a normal, happy life. Using these specialized diets to initiate a food trial, you can find out what your dog is reacting to and avoid it moving forward.
If you think your dog is suffering from a food allergy, contact your veterinarian or a veterinary nutritionist to find out how you can modify your dog’s diet appropriately.
For more great insights into your dog’s health and wellness needs, check out the Pet Honesty blog.