Dogs that can’t stop scratching or seem to have constant stomach issues might not just be picky eaters. Food allergies are often the hidden cause and usually develop after a dog has been eating the same ingredient for a long time. It’s not always grains to blame either, proteins can often be the underlying trigger. Figuring out what’s causing the reaction can make a big difference in your dog’s comfort and overall health. These are the most common foods known to cause allergies in dogs and what to know about each one.
What Are Food Allergies?
A food allergy happens when your dog’s immune system mistakes a harmless ingredient for a threat and reacts to it. Instead of ignoring that food, the body mounts a defense, causing symptoms that range from nonstop itching to chronic ear infections or digestive distress. This reaction is different from a food intolerance, which usually affects only the stomach and doesn’t involve the immune system. Understanding this distinction helps determine whether your dog’s discomfort is coming from an allergic response or just a sensitivity to certain ingredients.
What Are The Symptoms of Food Allergies in Dogs?
The most common sign of a food allergy is itching, especially around the paws, face, ears, belly, and tail area. Dogs often lick or chew these spots until they become red and irritated, which can lead to secondary infections that make things worse.
Other symptoms include frequent ear problems, vomiting, diarrhea, gas, and skin rashes. Some dogs may also have watery eyes, sneezing, or more frequent bowel movements than usual. These symptoms can appear at any age, but many dogs start showing signs before their first birthday.
The Most Common Food Allergies in Dogs
There are a few ingredients that often play the villain in the story of food allergies. These common culprits range from proteins you’d expect to find in any dog bowl to some less obvious foes that might surprise you.
Beef
Beef shows up in countless commercial dog foods, which makes it one of the most common sources of food allergies in dogs. When the same protein appears in every meal, a dog’s immune system can start to overreact to it over time. The result is constant itching, ear infections, and sometimes digestive problems that seem to appear out of nowhere. Rotating proteins and reading ingredient labels can help prevent this issue, and a break from beef often makes a noticeable difference in symptoms.
Dairy
Dairy can be tricky because it causes two very different problems, just as it can in humans. Some dogs are lactose intolerant, which means their bodies can’t digest milk sugars properly, leading to gas, bloating, or loose stools. Others have a true allergy to dairy proteins, which can cause itchy skin, ear inflammation, and rashes. If your dog shows signs of either, skip the cheese and yogurt treats for a while and talk with your vet about alternatives that are easier to digest.
Wheat
While not as common as meat allergies, wheat still triggers reactions in some dogs. Many lower quality dog foods use wheat as a cheap filler, which means dogs end up eating it far more often than they should. The proteins found in wheat can set off an immune response that leads to red, itchy skin or frequent ear infections. Some dogs also develop mild digestive upset when they eat foods heavy in grains. A switch to a grain-free or limited-ingredient diet often helps, but it’s best to make that change under veterinary guidance to keep meals nutritionally balanced.
Eggs
Eggs are packed with nutrients, but for some dogs, the proteins in the whites or yolks can cause an allergic reaction. Symptoms can include skin irritation, redness, or recurrent ear problems. Since eggs hide in more foods than you might think, it helps to check the ingredient list on packaged treats and kibble. If your dog improves after avoiding them, it’s a good sign that eggs were the culprit.
Chicken
Chicken is one of the most common proteins used in dog food, so it’s not surprising that it also tops the list of allergens. Dogs who eat chicken every day may suddenly develop sensitivities, showing symptoms like itchy paws, constant licking, or recurring skin infections. Switching to a different protein, such as salmon, turkey, or venison, can help reset their system and ease those flare-ups over time.
Lamb
Lamb used to be the go-to choice for dogs with food allergies because it was considered a “novel” protein. Over time, it became common in many commercial foods, and as a result, some dogs now react to it as well. Allergies to lamb can cause skin inflammation, patchy fur, and ongoing digestive upset. If your dog shows signs after eating lamb, try another protein that isn’t as common in their diet.
Soy
Soy appears in many processed dog foods and treats, even in brands marketed as “healthy.” For sensitive dogs, it can trigger itching, chronic ear infections, and digestive issues. Because soy is used as a filler or plant-based protein source, it can be hard to spot unless you check the label carefully. Removing soy from your dog’s meals often leads to fewer stomach problems and clearer skin within a few weeks.
Using an Elimination Diet to Diagnose
The only reliable way to identify a food allergy is through an elimination diet. This process usually takes several weeks and involves feeding your dog a simplified diet with just one protein and one carbohydrate source they haven’t eaten before. In some cases, a vet may recommend a hydrolyzed protein diet, where the protein is broken down into smaller pieces so the immune system won’t recognize it.
Once symptoms improve, ingredients are reintroduced one at a time to pinpoint the exact trigger. It requires patience, but it’s the most effective way to get clear answers.
How to Treat a Food Allergy in Dogs
Managing a food allergy means permanently avoiding whatever ingredient caused the reaction. For some dogs, this can be as simple as switching to a new food formula that doesn’t contain the offending protein. Dogs with multiple allergies might need a prescription diet or one with limited ingredients to minimize exposure.
Some pet owners also choose to make homemade meals under a vet’s supervision to control every ingredient. Consistency is key, and with the right plan, most dogs experience significant relief once the trigger is removed.
Try this: Homemade Raw Dog Food Recipe
Related:
10 Foods That Clean Your Dog’s Teeth Just As Well As Brushing
13 Healthy Snacks You Can Share with Your Dog
Gina Matsoukas is an AP syndicated writer. She is the founder, photographer and recipe developer of Running to the Kitchen — a food website focused on providing healthy, wholesome recipes using fresh and seasonal ingredients. Her work has been featured in numerous media outlets both digital and print, including MSN, Huffington post, Buzzfeed, Women’s Health and Food Network.
