Gluten and its Effect on Dogs
Gluten and Your Dog Guide: Learn how Gluten can affect your dog's health.
What is Gluten?
Gluten is a protein that is found mostly in wheat but is also present in other cereal grains, including rye, barley, oats and buckwheat. It actually is a crude mixture of two other proteins, gliadin and glutenin. Grains that do not contain Gluten are rice, amaranth, millet, corn and quinoa.
What Does Gluten Do to Intolerant Dogs?
Most dogs tolerate wheat and other grains quite well and have no adverse effects from having them in their diet. Unlike cats, dogs can process both meat and plant products. Gluten normally is digested by pancreatic enzymes in the small intestine. However, some dogs – like some people – cannot tolerate gluten. In people, this condition is called “celiac disease.” In dogs, it is called “gluten-induced enteropathy,” “gluten intolerance” or “gluten sensitivity.” Dogs that are sensitive to gluten develop a chronic small intestinal inflammatory disease if they eat gluten. They have intermittent or persistent diarrhea, lose weight, develop a poor hair coat, lose body condition and just generally fail to thrive. Fortunately, gluten intolerance is not common in companion dogs.
How Does Gluten Cause Digestive Problems?
Dogs that are allergic to gluten have a delayed hypersensitivity (allergic) reaction when they eat food or treats containing cereal grains. Although the exact pathway of this disorder is not well-understood, it is thought that a gluten-intolerant dog’s immune system attacks its gastrointestinal tract when it comes into contact with gluten, damaging the tiny, hair-like projections lining the small intestine, called “villi.” Damaged villi can’t absorb key nutrients, such as proteins, carbohydrates, fats, vitamins, minerals and, in some cases, even water. As a result, affected dogs are malnourished even if they are eating a lot of food. They will lose weight and body condition and develop chronic diarrhea.
Which Dogs are Affected?
Gluten intolerance can affect any breed but is particularly well-documented in Irish Setters, Samoyeds and Soft Coated Wheaten Terriers. Owners usually see signs of this condition by the time a dog reaches 6 or 7 months of age.
How is Gluten Intolerance Diagnosed?
When assessing a dog with a history of diarrhea, weight loss, poor body condition and general ill thrift, most veterinarians will run routine blood and urine tests. They probably will also do a fecal examination for parasites, take abdominal radiographs (X-rays) and test for exocrine pancreatic insufficiency. The results of these tests in dogs that are sensitive to gluten are usually unremarkable. The only way to definitively diagnose gluten intolerance is to put the dog on a gluten-free diet for 2 to 4 weeks and look for improvement. The animal should gain weight and stop having diarrhea once gluten is removed. Then, gluten will be reintroduced into the diet. A diagnosis of gluten intolerance is confirmed if the dog relapses.
How is Gluten Intolerance Treated?
Fortunately, gluten intolerance is completely treatable. All symptoms will resolve when the dog is fed a grain-free diet. Treats containing wheat, rye, oats, barley, buckwheat or other cereal grains must be avoided. Wheat is the most problematic ingredient for gluten-sensitive dogs and is common in commercial dog foods. Genetically modified grains are especially risky for gluten-intolerant dogs. Interestingly, butterflies that come into contact with pollen from genetically altered crops suffer a number of health problems, and eventually develop odd genetic mutations. It is possible that a similar thing happens when dogs eat genetically modified grains – especially if their system can’t handle grain in the first place.