Is food sensitivity and food allergy in dogs the same thing?

W. Jean Dodds, DVM Hemopet:

Confusing food allergies with food sensitivities (or intolerances) is a common mistake, not only among dog guardians, but also among veterinary professionals. I often hear experts in the veterinary field refer to food allergies, when in fact they are talking about food sensitivities. This is unfortunate, because as long as the veterinary community continues to confuse these two very different immunological responses, our dogs likely will not receive the correct diagnosis and will continue to suffer. So, let me be clear. Food sensitivities and food allergies are definitely not the same thing.

The fact is that true food allergies are actually quite rare. If I had to estimate from personal experience, food sensitivities are at least 10 – 15 times more common than food allergies. So, if poor little Buddy is scratching incessantly or has chronic bowel problems, he’s probably suffering from a food sensitivity, rather than a food allergy.

So, the difference?

Food allergies reflect a more immediate immunological response. A classic example of a food allergy is anaphylactic shock caused by peanuts: as soon as the person or animal comes in contact with the allergen – the peanuts – their airway closes and they cannot breathe. This response is virtually instantaneous. Boom! The antigen (in this case, peanuts) triggers an immediate, and sometimes life-threatening, immunological and physiological reaction. Rashes, hives and swollen eyes are examples of less severe – but also serious – allergic responses. These are all called Type I hypersensitivity reactions. In the blood, they show up as antibodies to immunoglobulins E (IgE) and G (IgG) working together with immune complexes.

Food sensitivity (or intolerance), on the other hand, is typically a chronic condition and often does not involve an immunological response. It generally builds up over time – perhaps even after months or years of exposure to the offending food. Food sensitivity is caused by Types II and III hypersensitivity reactions. They show up in saliva or feces as antibodies to immunoglobulins A (IgA) and M (IgM). By detecting IgA and IgM antibodies, food sensitivity testing is able to clearly identify the specific food(s) causing the sensitivity or intolerance. It can also differentiate between food sensitivity and food allergy.

Although they are generally not life-threatening, food sensitivities can affect many different aspects of the dog’s physical well being. Common signs of food sensitivity include:
• GI tract issues similar to Irritable Bowel Disorder (IBD)
• Chronic scratching itchy skin
• Chronic burping and gas rumblings (borborigmi)
• Chronic skin, ear and foot infections, especially with yeast

The first step in providing the proper relief to dogs with food sensitivities is to accurately identify the offending ingredient(s). With the proper information, you can begin feeding your dog a diet that agrees with his body, and he can get back to doing what he does best – being a dog.

Dr Jean Dodds is a world renown vaccine research scientist about hypothyroidism in dogs, a growing epidemic often misunderstood among owners. She is also founder of Hemopet, a nonprofit animal blood bank in Southern California and has a new book out, “The Canine Thyroid Epidemic: Answers You Need to Know for Your Dog,” written with Diana R. Laverdure (Dogwise Publishing, $19.95).