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Natural Awakenings National

Pet Food Perils: Lurking GMOs May Hurt Our Pets

Jun 28, 2013 12:21PM ● By Dr. Michael W. Fox

Like a canary in a coal mine, dogs serve as sentinels, drawing our attention to health hazards in our shared home environment and in the products and byproducts of the food industry.

Multiple Health Issues

In the mid-1990s, as genetically engineered or modified (GE, GM or GMO), corn and soy were becoming increasingly prominent ingredients in both pet food products and feed for farm animals, the number of dogs reported suffering from a specific cluster of health problems increased. It also became evident from discussion among veterinarians and dog owners that such health problems occurred more often among dogs eating pet food that included GM crops than those consuming food produced from conventional crops.

The conditions most cited included allergies, asthma, atopic (severe) dermatitis and other skin problems, irritable bowel syndrome, leaky gut syndrome, inflammatory bowel disease, colitis, recurrent diarrhea, vomiting and indigestion, plus abnormalities in liver, pancreas and immune system functions. People often reported failed treatments and harmful side effects to prescribed remedies (e.g. steroids), as well as problems with various manufactured prescription diets after their attending veterinarians diagnosed their animals with these conditions.

According to a 2011 study in the journal Cell Research, in engineering crops like corn and soybean, novel proteins are created that can assault the immune system and cause allergies and illnesses, especially in the offspring of mothers fed GMO foods. Diminished nutrient content is a concurrent issue.

“The results of most of the few independent studies conducted with GM foods indicate that they may cause hepatic, pancreatic, renal and reproductive effects and may alter hematological, biochemical and immunologic parameters,”concluded Artemis Dona and Ioannis S. Arvanitoyannis, of the Department of Forensic Medicine and Toxicology at the University of Athens Medical School, in their 2009 study on the effect of GM foods on animals.

“Look first for the USDA Certified Organic label. Next, look for other words and terms on the package indicating it comprises natural, humane, free-range, grass-fed and GM- or GE-free ingredients. Watch out for chemical preservatives, artificial coloring, byproducts, GMOs, irradiation/radioisotope treatment, hormones and antibiotics. In short, seek out whole organic foods appropriate to the species.”
~ Dr. Michael Fox


Such problems are caused partly by the inherent genetic instability of GM plants, which can result in spontaneous and unpredictable mutations (Biotechnology and Genetic Engineering Reviews). DNA in GM foods is altered by the genetic engineering process; it can be incorporated by gut bacteria and may alter their behavior and ecology in the digestive tract. Likewise, when digestive bacteria incorporate material from antibioticresistant genes, engineered into patented GM foods crops to identify them, it could have serious health implications, according to Jeffrey M. Smith in his book, Genetic Roulette, and Terje Traavik and Jack Heinemann, co-authors of Genetic Engineering and Omitted Health Research.GMO-Free Pet Food

What Pet Owners Can Do

Look for pet foods that are free of GM corn and soy, and/or organically certified. Pet food manufacturers that use U.S. Department of Agriculture (USDA) certified organic ingredients—and especially those that don’t use corn, soy, canola, cotton byproducts (oil and cake) or sugar beet, which are more commonly genetically engineered, or imported rice, which can have GM strains—can legitimately claim “No GMO Ingredients” on their packaging.

Information, plus tips on avoiding hidden GMO ingredients are available at NonGMOShoppingGuide.com. Many websites also provide recipes for home-prepared diets for companion animals, including DogCatHomePreparedDiet.com.

Let responsible pet food manufacturers know of consumers’ concerns and heed Hippocrates’ advice to let our food be our medicine and our medicine be our food. Enlightened citizen action is an integral part of the necessary revolution in natural agriculture aimed at promoting more ecologically sound, sustainable and humane farming practices, a healthier environment and more healthful, wholesome and affordable food for us and our canine companions.


Michael Fox, author of Healing Animals & the Vision of One Health, is a veterinarian with doctoral degrees in medicine and animal behavior. Find GMOfree pet food brands and learn more at DrFoxVet.com.

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