The best dog food for allergies depends on the cause of your dog’s symptoms. Hydrolyzed dog food is often recommended for dogs with diagnosed food allergies because the proteins are broken down into smaller pieces that are less likely to trigger an immune response. Limited ingredient diets can help identify and avoid specific allergens, while grain-free dog food may benefit dogs with grain sensitivities but is not the best choice for most food allergies.

If your dog keeps scratching and licking its paws, developing ear infections, experiencing stomach problems, or is diagnosed with allergies, you may wonder whether the food is responsible for the problems. Then, when you visit the pet food aisle, you’ll encounter a challenge when you see numerous options for hypoallergenic, limited-ingredient, grain-free, sensitive-skin or sensitive-stomach formulas, often all on the same bag. Which one is right for your dog and their body? 

Although these labels are frequently used interchangeably, they do not represent equivalent results. A dog with a true food allergy generally will require a highly restricted diet, such as that used for the Wellness Simple formulas. On the other hand, dogs with sensitive stomachs usually respond better to the Wellness formulas designed for easy digestion and sensitive stomachs. 

Understanding the intended effects of various food formulas will help you communicate more effectively with your veterinarian and choose a diet appropriate for your dog’s individual needs.

Dog Food Allergy Symptoms: Signs of Food Sensitivity in Dogs

Recognizing the appearance of a food sensitivity in your dog is an important initial step prior to making any purchasing decisions. Dogs with adverse food reactions may develop signs of skin or gastrointestinal disease, and in some cases both types of clinical signs occur simultaneously. Major signs of food sensitivity in dogs include: 

• Itchy, inflamed or reddened skin
• Frequent licking or chewing of the feet
• Frequent licking or chewing of the feet
• Excessive scratching of the face, ears, abdomen or hind limbs
• Recurrent infections of the skin
• Loose stools or diarrhea
• Increased frequency of defecation
• Excessive flatulence
• Vomiting or other signs of gastrointestinal disease

However, it is important to recognize that none of these clinical signs are specific for food sensitivity. Similar clinical signs may result from environmental allergies, food allergies, infestations with fleas or other parasites, infections of the skin, disorders of the gastrointestinal tract and numerous other diseases. Because of this, it is essential to work with your veterinarian to systematically eliminate other potential causes of clinical signs. This effort should continue until the remaining clinical abnormalities represent a confirmed intolerance to food, an allergic reaction to food or a sensitive gastrointestinal tract. 

Food Allergy vs. Food Intolerance vs. Food Sensitivity in Dogs

These terms are often confused as well. Food allergy refers to an immune response to a component of the diet, generally a protein. Whereas a food intolerance is an adverse response to food that is not mediated by the immune system. And then to compound the confusion the term food sensitivity is widely used by pet owners and pet food manufacturers, but encompasses a broader and less precise medical definition. For example, a dog with a “sensitive stomach” may have difficulty digesting a particular food or diet, but not an actual food allergy. 

The confusing part is that clinical signs generally do not distinguish among these conditions. Your vet can help rule out other causes (there are many conditions that look like food reactions but aren’t), and if a food issue is genuinely suspected, they can guide you through a properly controlled elimination diet. 

How Are Dog Food Allergies Diagnosed? The Elimination Diet Trial

No blood, saliva or hair tests reliably diagnose food allergy in dogs. The only acceptable method of diagnosing a food allergy is with a carefully controlled elimination diet followed by a food challenge. 

During the elimination phase, the veterinarian selects a diet that eliminates proteins to which the dog’s immune system may respond. No other foods, including treats, table scraps, medicated or flavored supplements, chew toys or medicated diets, should be given at this time unless specifically authorized by the veterinarian. 

Improvement in dogs with food-associated skin disease was achieved with elimination diets for an average of eight weeks in more than 90% of cases. Confirmation of the role of food as the cause of improvement was obtained with a food challenge. 

This represents a substantially greater degree of reliability than does trial of various diets with the hope that itching will resolve.

What Is Hypoallergenic Dog Food?

The term “hypoallergenic” has no official legal meaning for pet foods. Rather, it is a marketing term that refers to diets that reduce the likelihood of an adverse reaction to some component of the diet.

However, it is important to remember that “hypoallergenic” does not mean “allergy-proof.” No ingredient can be guaranteed to cause no reaction in all dogs. Hypoallergenic diets are based primarily on one of four general approaches.

1. Hydrolyzed Protein Dog Food

Because allergic responses to dietary protein depend on recognition of specific shapes of proteins by the immune system, reduction of protein size decreases the likelihood of an adverse reaction in sensitive dogs. These diets are commonly used for food allergy diagnosis, and for dogs with known adverse reactions to food; unfortunately, the extra processing step that is required to hydrolyze these proteins is relatively expensive. These foods can sometimes be cost-prohibitive to feed long-term.

2. Novel Protein Dog Food

The novel protein diet contains a protein that has not previously been consumed by the dog. This protein may be rabbit, venison, duck or another uncommon protein, and represents an individualized approach to the problem. 

Duck is not inherently hypoallergenic. If a dog has eaten duck for many years, it is no longer a novel protein for that dog. On the other hand, a common food protein like chicken will be novel for a dog that has never previously consumed it. 

3. Limited Ingredient Dog Food 

This is again a term with no legal definition and likely one of the most misused and confusing marketing terms used in pet food aisles today. When talking to a veterinarian, a true limited ingredient dog food uses fewer ingredients than usual and typically describes a diet with one primary animal protein and a small number of other ingredients, such as one carbohydrate, and fortified with minerals and vitamins. 

Using fewer ingredients facilitates identification of the components of a dog’s diet, but does not necessarily produce a hypoallergenic diet. For example, a diet containing only five ingredients may still cause health problems if one of the ingredients is an allergen for the dog. 

Yet a simplified formula may provide several benefits as it facilitates recognition of major sources of protein in the diet, avoids exposure to an ingredient known to be unacceptable to the dog, reduces the number of different proteins to which the dog is exposed, and provides an alternative diet for dogs with sensitive skin or gastrointestinal tract. The Wellness Simple formulas offer an extensive lineup of formulas that fit into this category. 

Can I Use Limited Ingredient Dog Food for an Elimination Trial? Sometimes, but not simply because the bag says “limited ingredient.” For proper elimination trials, veterinarians frequently select a special prescription diet. Some studies have shown that certain commercially available diets labeled as “limited ingredient” actually contain unlisted animal proteins and therefore may compromise the ability to obtain well-defined results for the trial, depending on the sensitivity of the dog. Still, a commercially available limited-ingredient diet remains an excellent choice for the appropriate dog. It should not, however, automatically be equated with a diet selected by a veterinarian for diagnostic purposes. 

4. Grain-Free Dog Food

Grain-free diets for dogs are simply diets that contain no grains such as wheat, corn, rice, barley or oats, but instead rely on other carbohydrates such as potatoes, sweet potatoes, peas, lentils and chickpeas. 

Grain-free does not mean allergy-free. Most food allergies of dogs are attributable to proteins, not to grains. Allergies to animal proteins are far more common than allergies to grains. Reactions to wheat are most frequently associated with adverse food reactions in dogs. 

For example, a dog allergic to chicken would not be helped by feeding a grain-free diet that still included chicken. The animal protein remained unchanged and therefore caused continuation of the allergic reaction. 

Should I Switch to Grain-Free Dog Food for Itchy Skin? Not automatically. A grain free diet helps dogs only that are truly allergic to grains. Eliminating all grains generally will not resolve most cases of pruritus or adverse food reactions unless your dog is allergic to wheat or another grain. 

Also, grain-free diets have been questioned as being associated with the development of a disease of the heart muscle called dilated cardiomyopathy. Reports of this disease have been received for dogs fed both grain-free and conventional diets. It has not been established that removal of grains causes dilated cardiomyopathy, but further research is needed to define the relationship between diet and this disorder of heart muscle. If concerned please follow up this discussion with your veterinarian. 

What Foods Cause the Most Allergies in Dogs?

The most common food allergens for dogs with food-induced skin disease identified in a 2016 study were beef, dairy products, chicken, and wheat.(1) Unfortunately, this study has not been repeated, so the true incidence and top offenders are not known. 

It’s important to note that this does not indicate that these ingredients are harmful on their own. Rather, they are frequently encountered in studies of food allergy because they have been consumed so extensively over the years. The more frequently a dog consumes a particular protein, the greater the likelihood that a sensitive animal will develop an allergic response to that protein. Dogs can become allergic to virtually any protein present in the diet. So, selection of an appropriate elimination diet must be based on previous dietary experience for each individual dog, and not simply on avoidance of a conventional list of “common allergens.”

Let’s Summarize: Hydrolyzed vs. Limited Ingredient vs. Novel Protein vs. Grain-Free: What’s the Difference?

Diet Type	What It Does	Potentially Used For	Does NOT Guarantee
Hydrolyzed Protein Dog Food	Changes the protein itself	Food allergy diagnosis; adverse food reactions	Allergy-proof
Novel Protein Dog Food	Changes the protein source	Elimination trials; avoiding previous proteins	Inherently hypoallergenic
Limited Ingredient Dog Food	Reduces the number of ingredients	Sensitive skin/stomach; avoiding known triggers	Hypoallergenic; diagnostic diet
Grain-Free Dog Food	Removes grains	Confirmed grain sensitivity	Allergy relief; help with protein allergies

These groups can overlap, but should not be used interchangeably. For example, a food may be both grain-free and contain a novel protein, or may contain hydrolyzed protein with inclusion of a grain inappropriate for a particular dog. For that reason, evaluation of the entire food is necessary, rather than reliance on individual words or claims on the label. 

Ingredients to Watch For: What Should You Avoid in Dog Food?

It’s best practice to avoid diets that include ingredients primarily for color, visual appeal, or marketing appeal, as they may add complexity without contributing meaningful nutritional value. But rather than looking for vague terms such as “no fillers,” read the ingredient list and ask: “What purpose does this ingredient serve in this formula?” This philosophy of purposeful formulation is an important part of the Wellness approach: ingredients are selected to serve a defined nutritional, functional, sensory, or food-safety purpose rather than simply to make the ingredient list sound appealing.

Choosing the Right Food for Your Dog’s Sensitive Skin or Stomach

True food allergies are rare in dogs. About 1 to 2% of dogs evaluated by veterinary clinicians have a food allergy, but the prevalence is higher for dogs treated for long-term pruritus or dermatologic disease. Food allergy is only one of many mechanisms by which dogs develop adverse reactions to food. In addition, dogs develop nonallergic food intolerance or sensitive gastrointestinal tract function.

If Your Dog Has Occasional Digestive Sensitivity

These conditions are difficult to define, and may reflect specific characteristics of the diet such as source of protein, degree of fat, type of fiber or extent of digestibility. Use of a simple, well considered diet is most effective for management of the sensitive dog. Use of diets like the Wellness Sensitive Skin and Stomach Recipes is all formulated for a sensitive stomach and may be appropriate. These diets contain highly digestible ingredients, appropriate sources of fiber, pre- and probiotic supplements or other nutritional components that promote normal gastrointestinal function and quality of feces.

So, What’s the Best Dog Food for Allergies?

The best dog food for allergies is not determined by whether “hydrolyzed protein,” “grain-free,” “limited ingredient,” or “hypoallergenic” appears on the front of the package. 

It is the diet that meets your dog’s complete nutritional needs while avoiding the ingredient or ingredients that your individual dog cannot tolerate. 

For dogs who simply do better with carefully selected ingredients or need nutritional support for sensitive skin or digestion, Wellness offers a variety of formulas designed with different nutritional needs in mind. The right choice depends on your dog’s individual history, preferences, and nutritional needs. 

And when you suspect a true food allergy, especially when your dog has persistent itching, recurrent ear or skin infections, or ongoing gastrointestinal problems, talk with your veterinarian before beginning a series of food changes. A properly designed elimination trial can help move the process from guessing at what your dog shouldn’t eat to identifying what actually works for them.

1. Mueller, R. S., Olivry, T., & Prélaud, P. (2016). Critically appraised topic on adverse food reactions  of companion animals (2): common food allergen sources in dogs and cats. BMC veterinary  research, 12(1), 9.