How to Know if Your Pet Needs Gluten or Grain Free Dog Food
By Lorie Huston, DVM
Choosing a diet for your dog is a task that should not be taken lightly. Grain free and gluten free pet diets have become extremely popular. This popularity has mirrored the appearance of similar products for people. These diets are particularly helpful for people that have celiac disease, intolerance to glutens in general, or allergies to wheat.
Many pet owners choose to mimic their own food choices when choosing a food for their pet. With the increase in the number of people choosing to consume a grain free or gluten free diet, pet food manufacturers have recognized that similar pet diets are attractive to pet owners. The popularity of these diets has led to an increase in the number of grain free and gluten free diets available for pets.
Are these diets the best choice for your dog? How do you know if your pet needs a grain free or gluten free dog food?
Grain Free Versus Gluten Free
Let’s start by discussing the difference between a grain free and a gluten free diet. Grain free dog foods are, as the name implies, diets that do not contain grain. Gluten free dog food, on the other hand, may or may not contain grain as an ingredient. Gluten is the protein that is found in specific types of grain, namely wheat, barley, and rye. Gluten free dog food is, of course, free of these proteins. However, not all grains contain gluten. Therefore, gluten free dog food may or may not be grain free, while grain free dog food will always be gluten free.
Does My Dog Need a Grain Free Diet?
Most dogs do not actually require a grain free or a gluten free diet. But how do you know if your dog does require one of these diets? To answer that question, let’s take a look at some of the common reasons pet owners choose to feed their dog a grain free or a gluten free diet.
Proponents of grain free diets claim that grains are an unnatural source of nutrition for our dogs. They argue that ancestors of our current-day dogs did not eat grains. While their ancestors may not have eaten grains, dogs have evolved to be able to digest grains and glutens pretty easily. Dogs possess several genes that have been modified through the course of their evolution to allow them to easily digest carbohydrates.1 That includes grains. So, while most dogs do very well eating a grain free diet, these diets are not required in terms of metabolization.
Another reason that many dog owners choose to feed grain free or gluten free dog foods is a mistaken belief that these diets are the best choice for dogs that have food allergies. While food allergies do occur in pets, corn and other grains are not among the most common allergens found in foods. In fact, according to some of the available research, corn is actually one of the least likely sources of food allergy. In one literature review, 278 dogs with food allergy were evaluated and the problem ingredient was clearly identified for each dog. Beef was the most common allergen, being responsible for 95 of the cases reported. Dairy was responsible for 55 cases, making it the second most frequent cause. Corn was identified as the offender in only 7 cases.2
For dogs that truly do have allergies to grains, a grain free diet would be an appropriate choice. The following are symptoms that would be expected in dogs that have food allergies (or other types of allergies):
- Excessive hair loss
- Bald patches
- Inflamed skin
- Sore and scabs
- “Hot spots”
A food trial with a grain free food would be necessary to determine whether the food is beneficial for your dog.
Does My Dog Need a Gluten Free Diet?
Unlike in people, celiac disease is uncommon in dogs. As a result, most dogs do not require a gluten free diet. The exception to this is the Irish Setter. A small number of Irish Setters have been documented to suffer from a congenital disease that results in an intolerance to gluten. This has only been reported in certain Irish Setters and only in the Irish Setter in the U.K. These dogs, however, will benefit from a gluten free diet.
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