Food Allergies in dogs and cats - How marketing affects their health

A significant percentage of dogs and cats now have food intolerances and allergies thanks in large part to the poor quality, biologically inappropriate ingredients in commercial pet foods. Pet food manufacturers have found another niche they are quickly trying to fill with "specially formulated" varieties of pet food. They are now offering "allergen-free" varieties for dogs and cats with GI issues like diarrhea, irritated skin, poor coat quality, itchy red ears, and other symptoms of food sensitivities.

Here are the first five ingredients in a popular "prescription" formula for dogs with an adverse reaction to food:

  • Starch
  • Hydrolyzed Chicken Liver
  • Soybean Oil preserved with BHA, propyl gallate and citric acid
  • Hydrolyzed Chicken
  • Powdered Cellulose (sawdust!)

Marketing claims for this product are based on identifying protein as the primary culprit in food intolerances, and specifically, 'intact animal protein.' That's why the formula boasts hydrolyzed chicken liver along with hydrolyzed chicken.

According to, preparing hydrolyzed food product (in this case chicken) for animal consumption involves the following process:

A food product for animal consumption is prepared from an animal by-product, preferably a complete avian carcass not fit for human consumption. A heated hydrolyzing agent is applied by spray or dip coating to the carcass exterior. After initiation of hydrolysis, the carcass is ground, enhanced by additives, then steam heated to a temperature of about 200 degrees F.

The heated by-product is provided as a slurry or as dry particulates to a twin screw extruder. As it is transported across several zones of the extruder, the by-product is thoroughly dispersively mixed and subjected to high pressures and temperatures, vented to release moisture, neutralized with a neutralizing agent, and blended under high temperatures and pressures sufficient to completely sterilize what has become a highly uniform and homogeneous by-product mass. The by-product mass is extruded and cut into pellets, which then are dried to a moisture content at or below 10 percent.

Makes you want to run right out for a hydrolyzed chicken dinner, doesn't it?

So, what are those "low-quality" proteins that are being use?

As regular readers of my website know, in my experience pets fed high-quality, human-grade protein from a variety of animal sources do not typically develop allergies to protein. It is when the same protein - and especially low-quality protein - is fed day in and day out for months or even years, that intolerance to a specific protein or ingredient develops. Many pet owners find an inexpensive commercial pet food formula at their local grocery story that their dog or cat gobbles up - and they feed it exclusively for long periods of time (sometimes for the life of the pet!). Eventually, many if not most of these pets develop sensitivity to certain ingredients, often the low-grade source of protein included in the formula (many sensitivities can also be attributed to the additives, i.e. colorings, flavorings, preservatives, etc.).

Contrary to what marketing claims for this allergen-free formula would have you believe, the problem isn't "intact animal protein." The problem is poor quality protein that is difficult for your pet's body to digest and assimilate, fed exclusively over several months or years.

So, what is "low-quality" protein?

Here's what has to say: Allergen-free pet food is an extremely low-nutrient food relying on starch to hold it together and hydrolyzed chicken [or hydrolyzed chicken liver] as the primary source of protein. Soybean oil provides a small amount of additional low quality protein. We note, however, that soy is one of the most common causes of food allergies in dogs and in this instance is preserved with a chemical (BHA) that is believed to be carcinogenic.  [When this review was written in January 2007, the formula also contained ethoxyquin*, which has been banned from use in human food because it, too, is showing to be a carcinogen. Current labeling for this product does not list ethoxyquin. Also note, unless soy and corn products state Organic Non-GMO, they are all GMO.

Powdered cellulose is a filler used in many pet foods – better known as sawdust.

*Please NOTE: Foods that contain ethoxyquin BEFORE they enter the pet-food manufacturing plant are not noted on the label [i.e. fish are often injected with ethoxyquin at the dockyards to preserve freshness. I believe that Canada is the only country that does not do this routinely.]

Overall - and ironically -  Allergin-free pet food formulas are very low-quality products!

If you're feeding your dog or cat a balanced, biologically appropriate diet that includes regularly rotated protein sources, chances are you don't need to be concerned about allergy-free food. Dogs and cats develop allergic reactions to low-quality protein, grains, additives and preservatives. And it makes perfect sense when you think about it.Your carnivorous pet's physiology isn't designed to handle a steady diet of meat byproducts, corn, rice, barley, soy, wheat, wads of potato or other starches [that convert to sugar], or potentially toxic chemicals. Instead, what your pet's body needs to thrive includes: 

  • Plenty of high-quality animal protein from muscle meat
  • Moderate amounts of animal fat
  • High levels of EPA/DHA (omega-3 essential fatty acids)
  • Loads of moisture (prey is about 70 percent water)
  • Just enough veggies and fruits to mimic the stomach contents of prey [I recommend pureeing veggies to "predigest" them for your pet]

To be optimally healthy - which includes avoiding food that create sensitivities and building resistance to all types of allergies - your dog should be fed a balanced, species-appropriate diet (see my Turkey Recipe for canines).

The diet I recommend is preferably raw, and either homemade (again, as long as it's balanced with added supplements) or organic commercial. Rotating the protein sources your pet eats is extremely important, as is strictly limiting or eliminating grains.

If you suspect your pet has food allergies ...

The goal when your pet has a food intolerance or allergy is to find the source of the problem and solve it. Buying an 'allergen-free' pet food, especially a poor-quality one, will neither reveal the source of the allergy, nor adequately nourish your dog or cat.

If your pet is a dog over a year old, consider using Dr. Jean Dodds' Nutriscan saliva test to determine if your pet is allergic to beef, corn, wheat, soy, eggs and/or milk.

If you've been feeding your pet the same food day in and day out for a period of months or years, he might have a sensitivity to the protein source. Also, chances are the meat is loaded with antibiotics and hormones, which can cause the immune system to over react. He has very likely also grown sensitive to certain allergenic ingredients in the food, typically grains and other carbohydrates, as well as the pesticides sprayed on grains.

Work with your holistic vet to develop an allergy elimination diet to help pinpoint the source of the problem. I recommend a three-month diet, which is longer than what many vets suggest. I like to give adequate time for an animal's body to clear the allergenic substances, detoxify, and clean out cellular debris.

At the end of the elimination diet, new foods are added back in slowly, one at a time to gauge your pet's response. It's not uncommon for pets to be able to re-incorporate previous problem foods or clean proteins into the diet once the body is detoxified and the GI tract is healthy again.

Please Note: that with all animals - humans as well - detoxification can cause other symptoms as the body clears out the contaminants ... diarrhea, skin eruptions, etc. may be common, but give it time and be patient. Your holistic vet should also suggest natural herbs and supplements to help with detoxification, allergy relief and immune system support during and after the elimination diet.

Exerpts taken from Dr. Karen Becker's FREE newsletter