Dog Food Allergies 101
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Dogs, like humans, can suffer from food allergies. These food allergies can cause a wide range of symptoms which vary in severity. Understanding the causes and what to do if your dog has an allergy will help ensure your dog lives a long and healthy life.
What Causes Food Allergies and How Can They Affect Your Dog?
Like other allergies, food allergies are the result of an overactive immune system. When a dog with a food allergy eats a usually harmless ingredient, his body misidentifies the substance as harmful and kicks into overdrive to try to isolate and remove it from the dog’s system.
How does the dog’s body try to protect itself from allergens? Their body releases histamines that push the allergen to the surface of the skin and makes the dog itch and itch.
Food Allergies vs. Food Intolerance
Most dog owners refer to food intolerances as “allergies”. And in many ways, they are very similar. In both, the dog’s body fails to process an ingredient correctly.
As Dr. Justin Shmalberg, a Doctor of Veterinary Medicine (DVM), points out, food allergies and food intolerance both fall into the category of cutaneous adverse food reactions. This means they both cause skin irritation, and both can create gastrointestinal issues like diarrhea and vomiting.
Basically, allergies cause the body to attack the substance it sees as dangerous while a food intolerance simply means that a dog can not break it down and derive any nutrition from it, and expels it in a semi-digested form. Their immune system simply does not activate.
Both adverse food reactions can cause digestive issues, but skin problems occur more frequently and consistently.
Signs and Symptoms of Food Allergies
If you’ve ever had an allergic reaction to an airborne substance, your body likely mildly reacted – you probably sneezed, maybe your eyes got itchy and your nose runny. If you have an allergic reaction to a food, it’s your digestive system that plays the leading role and works hard to rapidly get rid of or neutralize the irritant, causing pain and nausea. Some severe allergies can also result in swelling and constricted airways. The same is true for dogs except for one major difference: dogs have long-term skin conditions as a result of food allergies. In fact, the most common sign of a food intolerance or allergy in dogs is itchy, flaky skin.
Other common symptoms include:
- Itchy ears and feet
- Ear and skin infections
- Swollen lips, ears, or eyelids
Less Common Symptoms of Food Allergies
While those listed above are the most common symptoms, some dogs react more strongly to food allergies and intolerance by having trouble breathing, seizures, UTIs, weight loss, and nasal discharge.
Other rare signs of adverse food reactions can present in your dog’s personality and behavior. When a dog is uncomfortable he will often pace, rub against furniture, or exhibit head shaking, withdrawal, and lack of appetite.
Many dogs begin showing allergic reactions from a young age while others don’t show any signs of an allergy or food intolerance until they’re adults since it can often take time to develop. A dog that seemingly stops being able to process a certain ingredient out of nowhere has actually been developing that allergy over time.
The Most Common Dog Food Allergy Is Not What You’d Think
Dogs can be allergic to wheat, soybeans, preservatives, dyes, and various meats. But proteins tend to be the most common dietary culprit that dogs cannot digest. As a dog’s body begins to break down protein, it sees the protein as a dangerous substance and jumps into action. This can be either plant-based proteins or meat-based proteins.
Some of the most common allergens include:
These ingredients are reported as the most common allergens, but it’s important to note that other proteins and ingredients may not be as common. For example, how would you ever know if your dog is allergic to kangaroo if he’s never tried it?
Because a dog’s adverse reaction to a protein occurs when his body begins to process the protein, most veterinary nutritionists recommend hydrolyzed proteins. The hydrolyzed process breaks down proteins into tiny molecules so they can sneak by without being noticed by the immune system. Luckily, dog food companies are starting to incorporate hydrolyzed proteins in their formulas today.
Another option to help your dog avoid allergens is to feed him novel proteins, like duck, venison and salmon. These proteins are uncommon, so his body should not have previously reacted to them. This reduces the likelihood that your dog’s immune system will attack the proteins.
Allergies are often a double-or-nothing problem for many dogs, meaning dogs that have one allergy often develop or have other allergies as well.
How Do Veterinarians Diagnose Food Allergies?
Food allergies can be difficult to diagnose because commercial dog foods have a conglomeration of ingredients all mashed into kibble. This is compounded when a dog can no longer digest a food he once enjoyed. So, how do vets figure out what a dog is allergic to?
You’ve probably heard of “elimination diets,” but you may not know exactly how they’re effective in identifying allergens. These diets help dog owners, with the help of their vets, figure out what ingredient(s) their dog reacts adversely to. In fact, it’s really the only reliable way to diagnose a food allergy.
How Elimination Diets Work
Elimination diets work to identify what a dog can and cannot eat. Your dog does this by cycling through single-protein foods (often novel proteins) to see which he can process and which makes him feel sick and itchy. This process takes two to three months since it can take time for a reaction to occur.
What Can Happen If Your Ignore Your Dog’s Food Allergies?
The good news is that most allergies can be easily treated with diet changes, but what could happen if a dog’s food allergy goes unchecked?
A simple dog food allergy could morph into more serious physical and mental health problems. This can include anxiety and irritation to constant scratching and stomach discomfort.
Luckily, diet changes don’t have to be complex. Fresh dog food companies like NomNomNow, The Farmer’s Dog, and Spot & Tango take the guesswork out of handling your pups allergies through their diet.