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​The Poisons in Pet Food

by John Anderson
From the May 1998 issue of ALTERNATIVE MEDICINE magazine

A homeopath of our acquaintance, who specializes in animal health, recently reported that nearly all of her new cases are dogs and cats with cancer. This is a most unusual and alarming trend, she told us. One of the reasons American dogs and cats are getting very sick can be found in the pet foods they eat every day. The realities of animal health aren’t much different than human health: if you consume a diet of toxins, eventually you will get terribly sick.

Despite the appealing blandishments of pet food advertisements with their claims of providing "complete and balanced nutrition," if you’re not exceedingly circumspect, you may end up feeding your pet chicken heads, road kills, spoiled or moldy grains, cancerous material cut from slaughterhouse animals, tissue high in hormone or pesticide residues, and even shredded Styrofoam packaging, metal ID tags and minced flea collars.

Don’t expect the food label to be any true guide to the product’s contents. The list of ingredients on that bag of dry pet food or can of "meat" can mask the toxic horrors behind innocuous-sounding phrases such as "meat meal," "bone meal," and "meat by-products." It’s the substances you don’t know about in that can of pet food that may sicken or even kill your pet.

Rendering Garbage into Pet Food—Rendering is the process of grinding up and then melting down or cooking scrap material from animals. The final products of this process—meat and bone meal and squeezed-out-fats—are sold primarily to pet food companies.

The list of materials that go into the rendering process is extensive and horrific. When cattle, sheep and poultry are slaughtered for human consumption, the parts deemed unsuitable for eating—heads (including growth hormone implants in cattle), skin, fat containing pesticide residues, toenails, hair or feathers, joints, hooves, stomach and bowels—are rendered.

Other animal parts sent to rendering plants include cancerous tissues, worm-infested organs, contaminated blood and blood clots. Compounding these toxins, slaughterhouses add carbolic acid and fuel oil to these remnants as a way of marking these foods as unfit for human consumption.

Slaughterhouses aren’t the only source for animals that end up rendered. Animals classified as "4-D" (dead, diseased, dying and disabled)—that is, too unhealthy for human consumption—are rendered. These include animals with residues of antibiotics, such as chloramphenical and sulfamethazine, that are commonly used in meat production.

Road-kill animals and some deceased zoo animals are also sent to rendering plants. A report in the San Francisco Chronicle (February 19, 1990) presented evidence that dead pets from animal clinics and shelters are carted away to be rendered—with their name tags and flea collars intact. Other items tossed into the rendering "soup pot" are rancid grease from restaurants and supermarket meats that are no longer fresh (including their Styrofoam and shrink-wrap packaging).

All of this material is slowly ground up at the rendering plant, then chipped or shredded, and cooked for up to an hour at 220 degrees F to 270 degrees F. The fat or tallow separates during the cooking and is removed. What’s left over is then pressed to remove all moisture and crushed into what is misleadingly called "bone meal" or "meat meal."

Meat and poultry by-products, another major category of pet food ingredients, are the unrendered parts of the animal left over after slaughter, everything deemed unfit for human consumption. In cattle and sheep, this includes the brain, liver, kidneys, spleen, lungs, blood, bones, fatty tissue, stomachs and intestines. The items on this list that would normally be consumed by humans, such as the liver, would have to be diseased or contaminated before they could be designated for pet food. Poultry by-products include heads, feet, intestines, undeveloped eggs, chicken feathers and egg shells.

Other items counted as acceptable protein sources and included under "by-products" are dried animal blood and hair, dehydrated stomach contents from cattle and dried pig and poultry excrement. As explicit as the facts about pet food contents may be, you won’t find them listed on the label; the truth about these poisons is conveniently buried under the rubric "by-products."

The primary ingredient in many dry commercial pet foods is not protein but cereal. Corn and wheat are the most common grains used but, as with the meat sources, the nutritious parts of the grain are generally present only in trace amounts. The corn gluten meal or wheat middlings added to pet foods are the leftovers after the grain has been processed for human use, containing little nutritional value. Or they may be grain that is too moldy for humans to eat, so it’s incorporated into pet food. Mycotoxins, potentially deadly fungal toxins that multiply in moldy grains, have been found in pet foods in recent years. In 1995, Nature’s Recipe recalled tons of their dog food after dogs became ill from eating it. The food was found to contain vomitoxin, a mycotoxin.

Perfecting the Contamination – The nutritional needs of pets are hardly the concern of most manufacturers. Commercial pet foods are usually concocted with the profit margins in mind, and nothing else. A new food may be tested to see whether animals like it (eat it in large quantities), but not whether it is good for them. For dry foods, ingredients (meat meal, by-products, cereals) are mixed together with water or steam, pushed through a machine called an extruder which gives the food its shape, then cooked at high temperatures and dried. To make the food palatable to your pet, fats—often the tallow separated during the rendering process—is sprayed on after the food is dried. Wet foods are made from raw ingredients ground up with additives and preservatives. "Chunky" canned foods are run through an extruder to produce the look of natural meats.

Harmful chemicals and preservatives are added to both wet and dry food. For example, sodium nitrite, a coloring agent and preservative and potential carcinogen, is a common additive. Other preservatives include ethoxyquin (an insecticide that has been linked to liver cancer) and BHA and BHT, chemicals also suspected of causing cancer. The average dog can consume as much as 26 pounds of preservatives every year from eating commercial dog foods.

The manufacturing process destroys most of whatever minimal nutritional content remained from the dubious list of ingredients. Even when the companies include more healthy ingredients at the outset, manufacturing depletes the nutritional value. "Processing is the wild card in nutritional value that is, by the large, simply ignored," states R L Wysong, DVM, a veterinarian who founded Wysong Corporation to produce healthful pet foods. Proteins, enzymes, vitamins and minerals and fatty acids present in the foods can all be altered or destroyed by the manufacturing process, leading to nutritional deficiencies in the pets eating these foods.

Nobody’s Watching the Pet Bowl—No consumer agencies are looking out for your pet’s health interests. The pet food industry is virtually unregulated regarding food composition. In fact, information about the poisons in pet foods is not easily obtained; hence its shock-value when it’s finally revealed to the unsuspecting public.

The problem is that only the label, not content, of pet foods is regulated. The Association of American Feed Control Officials (AAFCO), a group of federal and state bureaucrats, define the ingredients listed on the labels of pet foods, but they do no testing on the foods themselves and have no enforcement authority. So don’t expect their semantics to keep your pet healthy.

The United States Department of Agriculture, a government agency you might think would be watching the pet food industry, only oversees food for human consumption, letting pet food makers off the leash. The Food and Drug Administration’s Center for Veterinary Medicine (FDA/CVM) concerns itself mainly with labeling: manufacturers must substantiate any health claims they make for their pet food, but they aren’t asked to prove that their food is not quietly toxic to pets. While the FDA/CVM can prohibit an ingredient’s use if it is proven detrimental to health, they do no ingredient quality testing on pet foods, so how will they ever know? The claims of "complete and balanced nutrition" on many commercial pet foods are based on AAFCO nutrient profiles.

What isn’t addressed on the label is the quality and bioavailablity of these nutrients. For instance, the label may state that the food contains a "minimum of 65% protein," but is it clean and can it be absorbed? The labels will never tell you. "Although the AAFCO profiles are better than nothing, they provide false securities," states Quinton Rogers, DVM, a veterinarian with the Department of Molecular Biosciences, Veterinary School of Medicine, University of California at Davis. "There is virtually no information on the bioavailability of nutrients for companion animals in many of the common dietary ingredients used in pet foods."

110 Million Sick Pets?—There are an estimated 55 million dogs and 63 million cats living in American households. Given the appalling condition of most commercial pet foods, it’s a wonder there are any healthy pets walking around anymore. "Nature never designed canine or feline kidneys to handle the volume of impurities that come their way," states veterinarian Al Plechner, DVM, author of Pet Allergies. "The result is fatigued, irritated, damaged and deteriorated kidneys after several years of life. Left untreated, the toxic buildup leads to vomiting, loss of appetite, uremic poisoning and death."

Recent studies have shown processed foods to be a factor in increasing numbers of pets suffering from cancer, arthritis, obesity, dental disease and heart disease, comments Dr Wysong. Dull or unhealthy coats are a common problem with cats and dogs and poor diet is usually the cause, according to many veterinarians and breeders. The AAFCO nutrient profiles may play a role here, in the "balanced" nutritional levels they recommend may be inadequate for an individual animal.

It is estimated that up to two million companion animals suffer from food allergies. Dr Plechner believes that the commercial pet foods are a primary cause and can contribute to a host of health problems. "Among pets, there is a widespread intolerance of commercial foods," he states. "This rejection can show up either as violent sickness or chronic health problems. It often triggers a hypersensitivity and overreaction to flea and insect bites, pollens, soaps, sprays and environmental contaminants."Feline urological syndrome, a chronic condition similar to cystitis in humans (characterized by frequent urination with blood in the urine), is an increasingly common and potentially fatal illness in cats. It has been linked to elevated levels of ash and phosphorus, two substances commonly found in commercial pet foods. High iodine levels are seen as a contributing factor for thyroid tumors in cats. "New diseases are being discovered that are linked to ‘100% complete’ diets," states Dr Wysong. These include "polymyopathy (a muscle disorder) from low potassium levels, dilated cardiomyopathy (heart muscle disorder) from low taurine levels, arthritic and skin diseases from acid/base and zinc malnutrition and chronic eczema from essential fatty acid malnutrition," he reports. Given the high possibility that your favorite pet foods may be slowly poisoning your cat or dog, it’s crucial that you prepare your own foods.