With the increasing awareness in human nutrition on the prevalence of gluten intolerance and coeliac disease, pet owners and pet food companies have jumped on the bandwagon and began marketing pet foods to be gluten and grain free.

But the real question is, how common are gluten allergies and intolerances in pets? What is gluten anyway and why is it in pet food? As a coeliac myself, I know how damaging this ingredient can be to my body, but does the same happen to pets? And should we be concerned about gluten as an ingredient, when it causes so many issues in humans?

Coeliac disease is an autoimmune disease with a genetic component, where the body attacks itself in the presence of gluten. When a coeliac ingests gluten, the body becomes confused and attacks the lining of the small intestine damaging the delicate microscopic fingers called villi, that line the intestine and allow the body to absorb nutrients from food – this is called villous atrophy. This damage impairs the gastrointestinal tracts ability to absorb nutrients from food, causing malnutrition and numerous other health conditions.

What is gluten?
Gluten is a storage protein found in a number of grains, namely wheat, barley, some types of oats, bran, spelt and rye. This protein is known for giving dough its elasticity and chewy texture. The storage proteins in other grains, such as corn and rice, are also sometimes called gluten, but they do not cause harmful effects in people with coeliac disease.

Can my pet have coeliac disease?
Coeliac disease, or more specifically, villous atrophy has only been described in one breeding line of Irish Setters. There have never been any cases of gluten causing villous atrophy in cats. As mentioned above, in humans the condition has a genetic component; there are a number of genes associated with developing coeliac disease. If someone has these genes, they have a strong chance of developing coeliac disease; for the gene to be turned “on” there is often an environmental trigger such as a stressful event or trauma, illness or exposure to gluten. Some people with the gene never develop coeliac disease, others show signs from birth. Family members of people positive for the coeliac gene have a 15% increased risk compared to the general public of also developing the condition. So, in the case of the Irish Setters who were positive for the genes that caused villous atrophy from gluten, the breeders no longer bred with these animals and have bred out this condition. Therefore, true coeliac disease does not exist in animals, at least not anymore.

What about grain and gluten allergies?
Grain allergies account for less than 1% of all food allergies. Food allergies themselves generally are caused by meat proteins (such as beef, chicken, lamb or fish) are already fairly uncommon (only 10% of all allergies are food based) with environmental allergens being the most common cause of reactions.

In a study of 278 cases of food allergies in dogs where the problem ingredient was clearly identified, beef was by far the biggest culprit (95 cases), accounting for 34% of cases. Dairy was number two at 55 cases (19%). Wheat came in third with 42 cases (15%). Soy and corn were actually minimal offenders, coming in at 13 (4.5%) and 7 (2.5%) cases, respectively.

Again, it is important to remember that if you suspect your pet has a food allergy, please seek the assistance of your vet in conducting a strict food elimination trial to determine what exactly your pet is allergic to before changing diets.

My dog has itchy skin and ear infections, is it gluten?
The short answer is no. Allergies that elicit a dermatological response are generally environmental such as pollens, grasses, fleas or dust mites. While a food allergy can sometimes trigger a skin reaction, it’s generally all year round (not seasonal) and all over the body or centered around the mouth and face, rather than causing the occasional ear infection or itchy belly.

But gluten and carbs are inflammatory!
Gluten is only inflammatory to people with coeliac disease, or a sensitivity to gluten. It is not inflammatory in any one else, or in pets. Gluten is also not a carb or a starch, it is a plant based protein but is often found in sources of carbohydrates; there is no evidence that carbohydrates are harmful, in fact they are energy dense and provide fibre, amino acids and essential fatty acids that are beneficial to both the pet and the pet’s microbiome.

What should I do if my pet does have a grain allergy?
First off, it’s vitally important we determine what grain your pet is allergic to. It is highly unlikely your pet is allergic to all grains; so a food elimination trial should be conducted to narrow down and diagnose which allergen is a problem for your pet. This makes it easier to then choose a food that is safe and balanced for your pet’s needs because if your pet is one of the rare cases that can’t consume wheat, there’s many diet options that use potato, rice, quinoa, oats or some other grain as an alternative.

I’m a coeliac, should my pet eat gluten free for my safety?

As a coeliac myself, I understand the concerns with handling gluten containing foods when feeding my pets. As I have cats, I don’t need to worry about them licking my face and potentially introducing gluten into my mouth. To cause a reaction, you need to consume gluten; coeliac disease sufferers may have varying levels of tolerance of gluten so may not always reaction to small amounts but it’s always important to take precautions. I recommend washing hands thoroughly or wearing gloves after handling pet food and/or wear a mask to avoid inhaling the dust from dry foods if it’s particularly powdery. For dog owners who are particularly sensitive or appear to react when their pet licks their face, you may want to feed a diet that is hydrolysed designed for pets with allergies and doesn’t contain gluten cereals anyway, instead uses rice as a carb source.

So why are grain free diets so popular if grain isn’t a common issue for pets?
Marketing. With the humanization of pets and the explosion in human nutrition of people cutting out gluten for health reasons, people began wanting to cut out gluten from their pet’s diets too, blaming them for all sorts of health issues. Pet food companies jumped on the bandwagon due to consumer pressure and brought out grain free foods to appeal to pet owners. However, now we know that grain free diets are linked to dilated cardiomyopathy in pets so are not the best choice for our companions. For more information, read my blog posts about grain free diets here.

Do you feed a grain or gluten free diet to your pet? Has this blog made you reconsider? Leave a comment below!

References

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4710035/

https://pubmed.ncbi.nlm.nih.gov/16527756/

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250806

https://www.tandfonline.com/doi/full/10.1080/01652176.2012.713170

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1576718/

What is gluten image source: https://www.issaonline.com/blog/index.cfm/2016/are-your-clients-thinking-about-going-glutenfree