What is Gluten in Nutrition?

Gluten isn’t a single substance but a set of proteins, mainly gliadins and glutenins, naturally found in some grains. These proteins are responsible for providing elasticity to flour dough, allowing bread and other baked goods to have a soft and chewy texture.

In the pet food industry, gluten has several roles, such as serving as a carbohydrate energy source and a binding agent to help combine ingredients, shaping, and providing consistency to kibble. Moreover, it enhances the texture and palatability of pet food, making it more attractive for pets, while also reducing cost.

Gluten sensitivity isn’t a traditional allergy or an autoimmune disease like celiac disease in humans, although it shares some characteristics. Gluten sensitivity occurs when gliadins and glutenins, found in grains like wheat, are not fully digested in the gastrointestinal tract of some animals. These partially digested fragments can trigger an inflammatory response. This chronic inflammation can damage the intestinal wall, increasing its permeability and allowing larger molecules to enter the bloodstream. Once in the bloodstream, these molecules can activate a more specific immune response, potentially causing tissue damage and clinical symptoms. Besides these immune mechanisms, non-immune factors like increased sensitivity to gluten’s irritating effects in the intestine or the influence of intestinal microbiota can also contribute to gluten sensitivity.

Which Dog Foods Contain Gluten?

Gliadins and glutenins, the proteins that make up gluten, are primarily found in dog foods containing certain cereal grains. The most common foods where these proteins can be found include:

• Wheat-Based Foods: Wheat is a common ingredient in many dog foods as it is an economical carbohydrate source. It should be avoided in all forms if gluten is not tolerated: whole, milled, bran, germ, etc
• Barley-Based Foods: Barley is another gluten-containing cereal used in some foods as a fiber and energy source. Its derivative, malt, should also be avoided.
• Rye or Triticale-Based Foods: Although less common, triticale (a wheat and rye hybrid) contains gluten and is present in some foods, which should be avoided by dogs with known gluten sensitivity.
• Some Oat-Based Foods: Oats themselves do not contain gluten, but they are often processed in facilities that handle wheat, barley, or triticale, leading to cross-contamination. Foods containing oats should specify “gluten-free certified.” The same applies to modified starch and hydrolyzed vegetable protein, which need a gluten-free origin specification.
• Some Treats and Supplements: It’s not just about food, so knowing which ingredients affect gluten intolerance and being able to recognize them on labels of treats and other dog supplements such as kibble and wet food is important.

What Gluten-Free Diet Alternatives Exist?

If your dog has gluten sensitivity, it’s important to choose foods formulated with alternative, gluten-free ingredients, known as “gluten-free dog food” or “grain-free dog food.” Safe options include rice, corn, potato, tapioca, or legumes like peas, lentils, or chickpeas. Foods using hydrolyzed proteins are also viable, provided the hydrolysis process removes allergens to ensure safety for dogs and other pets with intolerances or allergies.

How Does Gluten Sensitivity Develop in Pets?

Dogs with gluten sensitivity have a complex issue that, while not fully understood, is believed to arise from an interaction between genetic, environmental, and immune factors.

Genetic predisposition plays a significant role, suggesting that some dog breeds may be more susceptible to developing this condition, although specific responsible genes have yet to be identified. Breeds associated with higher incidence include the Irish Setter, Wheatens Terrier, Border Terrier, Soft Coated Wheaten Terrier, and less commonly, the Labrador Retriever.

A key contributing factor is pre-existing intestinal damage, which can increase intestinal permeability, allowing more gluten molecules to enter the bloodstream and trigger an immune response. This damage can result from infections, chronic inflammation, prolonged use of certain medications, stress, or an inadequate diet.

Additionally, changes in gut microbiota, known as dysbiosis, can increase the risk of gluten sensitivity. Dysbiosis is caused by factors such as an inappropriate diet, antibiotic use, stress, or infections, disrupting the balance of microorganisms in the gut and affecting digestion, immunity, and overall health.

Early gluten exposure is another factor, as some studies suggest it may increase the risk of developing sensitivity later in life, possibly because the immune system of puppies and young dogs is still developing.

Finally, environmental factors such as toxin exposure, chronic stress, excessive vaccination, and the use of certain medications may also contribute to the development of gluten sensitivity. Therefore, addressing gluten sensitivity requires comprehensive evaluation and an individualized approach considering all these factors.

How Can We Recognize Gluten Intolerance?

If you suspect your dog might have gluten intolerance, it presents a challenge as symptoms can be varied and similar to other conditions. However, while they can vary in severity and affected areas, the most common signs include:

Digestive Problems:

• Diarrhea: soft/liquid, frequent, and voluminous
• Vomiting: occasional or recurrent
• Flatulence: with abdominal bloating and discomfort and audible intestinal noises
• Loss of appetite and weight loss

Skin Problems:

• Pruritus (itching)
• Skin rashes
• Hair loss
• Dry or scaly skin
• Recurrent ear infections

Other Signs:

• Lethargy or lack of energy and decreased physical activity
• General malaise with discomfort or pain, whining, abnormal postures, or difficulty moving
• Behavioral changes like irritability, aggression, or anxiety

How to Confirm Gluten Hypersensitivity in Dogs?

If your dog might have gluten-related problems, it is crucial to consult a veterinarian. The vet can perform tests to rule out other potential causes of the symptoms and confirm intolerance. Tests may include:

• Clinical History and Physical Examination: The vet will collect information about the dog’s medical history, symptoms, and diet, and perform a complete physical examination to assess overall health.
• Blood Tests: To evaluate liver and kidney function, electrolyte levels, and the presence of inflammation.
• Fecal Analysis: To detect the presence of parasites, bacteria, or blood.
• Elimination Diet: This is the most common and effective test for diagnosing gluten hypersensitivity. The dog is fed a gluten-free diet for a set period (usually 4-8 weeks). If symptoms improve or disappear during this time, gluten is gradually reintroduced into the diet. If symptoms reappear after gluten reintroduction, gluten intolerance is confirmed.
• Intestinal Biopsy: In more complex cases, an intestinal biopsy may be performed to examine the lining of the small intestine for signs of inflammation or damage.

Conclusion: Gluten and Gluten-Free Foods for Dogs

The health and well-being of our canine companions can be compromised by gluten sensitivity, a condition that demands meticulous attention to their diet. While understanding mechanisms and factors contributing to this sensitivity is crucial, the key is prevention and management. Ensuring a gluten-free diet for your dog, identifying and avoiding problematic ingredients, is essential for those with predisposition or confirmed diagnosis. However, information alone is not enough. For accurate diagnosis, personalized nutritional guidance, and appropriate follow-up, consulting with a veterinarian becomes indispensable. Only then can we ensure a full and healthy life for our loyal friends, protecting them from gluten’s adverse effects and ensuring your best friend’s health.

FAQs 

How Can I Promote My Dog’s Microbiota and Reduce the Risk of Developing Sensitivity?

To promote healthy intestinal microbiota in your dog and reduce the risk of gluten sensitivity, consider incorporating probiotics and prebiotics into their diet. Probiotics are beneficial bacteria that help maintain and balance gut flora, while prebiotics are fibers that feed these bacteria. It is best to consult your vet to determine the most suitable probiotics and prebiotics for your pet and ensure that their diet is rich in fiber and low in processed ingredients. Additionally, avoid unnecessary antibiotic use, as they can alter intestinal microbiota.

Does Food Quality or Grain Processing Affect Gluten Sensitivity? Should I Prioritize “Whole” Grains or Specific Processing Methods?

The quality of grains and the processing methods of commercial foods can influence the likelihood of a dog developing gluten sensitivity. Whole grains, compared to refined ones, retain more nutrients and fiber, promoting slower digestion and lower glycemic response. However, gluten content is still the key factor for sensitive dogs, regardless of whether the grain is whole or refined.

Processing methods can also play an important role. Certain processes, such as high-temperature extrusion, can alter gluten proteins, potentially making them more or less allergenic to some dogs. However, scientific evidence on this matter is limited.

If you choose to include gluten-free grains, opting for whole and minimally processed options may offer additional nutritional benefits but always under veterinary supervision to ensure a balanced and suitable diet for the dog’s individual needs.

How Can I Conduct an Elimination Diet to Detect Gluten Sensitivity in Dogs?

To conduct an elimination diet effectively and safely, close collaboration with your veterinarian is essential. The protocol typically involves feeding your dog a novel protein and carbohydrate source (one they haven’t consumed before) for 4 to 8 weeks. It is crucial to avoid all other foods, treats, and supplements during this time to ensure a gluten-free diet. Ensure that the food chosen is complete and balanced to meet your dog’s nutritional needs. Once symptoms have improved, previously consumed ingredients are gradually reintroduced one by one to identify potential triggers.