Alicia Silverstone’s dogs have gone vegetarian, which the actress claims has even helped cut down on her dogs’ flatulence. She's a celebrity whose eating habits are headline-worthy, but she’s hardly alone in her decision.

More people are forgoing meat for a whole spectrum of reasons — from environmental to philosophical — and now vegetarians are taking a second look at their dogs’ meat-based diet — and cringing. As a result, more owners are putting their dogs on a vegetarian or even vegan diet to bypass the health and ethical dilemmas that come with a side of beef, pork or chicken in their pet’s kibble.

“I've been vegan for more than two years now, and I don't wish to contribute to the slaughterhouse or factory farm industry for my own food nor for my dogs’,” explains Debra Benfer, who together with her husband owns three vegan dogs. “If people really read what ingredients are put in dog food, I believe more people would understand why a vegetarian diet is the way to go.”

Some of those ingredients include meat from animals deemed unfit for human consumption, known in the pet food industry as the 4 Ds — dead, dying, diseased or disabled animals. In addition, many commercial pet foods contain “meat meal” or “byproducts,” which can include various animal parts and slaughterhouse waste that don’t exactly match the idyllic pictures of juicy meat chunks often seen on a bag or can of dog food. Much like commercial meat for humans, meat used in pet food can contain hormones, pesticides and antibiotics, a concern that has led many dog owners to seek alternative diets.

“If someone is saying it’s OK to give my dog these things, I would add a 5th ‘D’ to that equation and say ‘don’t,’” says Jill Howard Church, president of the Vegetarian Society of Georgia. “As a vegetarian, I know what’s in human meat and since the meat that falls below the human standard is what goes into pet food, it gives me cause for concern.”

Church's two dogs were on a vegetarian diet for their entire lives and lived to be a healthy 15 and 19 years old. Church currently has a 3-year-old black Labrador retriever that’s also thriving on a vegetarian diet.

Church and Benfer’s positive experience with vegetarian dog diets is mirrored in hundreds of testimonials found on the Web from owners who have successfully switched their dogs to a vegetarian diet. Some owners have bypassed the dog food industry altogether by cooking their own wholesome vegetarian dog meals.

“People are taking control of their animals’ diet back into their own hands instead of relying on the pet food industry so much,” says Greg Martinez, author of "Dog Dish Diet: Sensible Nutrition for Your Dog’s Health". “We’ve all been held hostage by industry a little bit.”

In addition to decreasing a dog’s carbon pawprint (meat production is a major contributor to greenhouse gas emissions), owners say that putting their dogs on a vegetarian diet has resulted in everything from longer life spans and shinier coats to decreased aggression.

However, there are those who worry that vegetarian dogs may not be able to get adequate nutrition from a plant-based diet. Dogs, like humans, are omnivores, meaning they can survive on a diet of either plant or animal origin, but owners must be careful to ensure that their dogs are getting the proper nutrients from plant-based ingredients. (Cats, on the other hand, are strictly carnivores.)

According to the Association of American Feed Control Officials (AAFCO), a non-regulatory industry group that establishes pet food standards, dog food for an average adult dog should contain about 18 percent protein, an amount deemed necessary for good health and proper growth and development. But since every protein source contains different levels of amino acids, which are protein’s building blocks, all protein is not created equal. Some proteins are better for pets than others. For example, egg and cottage cheese are considered quality sources of protein for dogs.

“Vegetarian proteins tend not to have all the amino acids, so you have to do multiple combinations of varying types of sources of protein to get the right amino acids, which can get a little tricky to manage,” says Dr. Jessica Waldman, a veterinarian who operates a full-time pet rehabilitation clinic in Santa Monica, Calif. Waldman says she steers her clients away from vegetarian diets because she believes they are unnatural.

“Although I think it would be possible to put a dog on a vegetarian diet, it is truly unnatural for them,” says Waldman. “There are still dogs in the wild and they eat a vast majority of animal protein, so I think that keeping your pet’s diet as close to natural is best for limiting disease and promoting health.”

Other vets disagree, arguing that dogs can successfully be vegetarians as long as their diet is balanced and they are able to get proteins from varying sources.

Dr. Jennifer Larsen, a veterinary nutritionist at the University of California-Davis, says that both commercial and home-cooked vegetarian diets “can be used safely and can provide adequate nutrition if carefully and appropriately formulated” and as long as owners pay special attention to providing their dogs with the proper protein and amino acids.

Commercial vegetarian diets and home-cooked options are prescribed by veterinarians for dogs with specific diseases, but there currently isn't much extensive research to prove or disprove their healthfulness. One survey conducted by PETA found that 82 percent of dogs that had been vegan for five years or more were in good to excellent health and that the longer a dog remained on a vegetarian or vegan diet, the greater the likelihood that the dog would have overall good to excellent health.

The study, however, also found that vegetarian dogs may be more prone to urinary tract infections as well as a form of heart disease known as dilated cardiomyopathy, which can be caused by a deficiency of the amino acids L-carnitine or taurine. But as the researchers pointed out, DCM isn’t just a problem for vegetarian dogs since L-carnitine and taurine also can be washed away in the processing of meat in commercial dog food.

To help bypass this problem, some commercial dog food companies like V-dog, a high protein vegan dog food, have added taurine and L-carnitine to their formulas to insure quality health that “exceeds the nutrient profiles established by the AAFCO,” says V-dog President David Middlesworth.

Though putting dogs on a vegetarian diet may remain controversial until further studies are conducted, veterinarians and vegetarian dog owners can agree that people considering putting their dog on a vegetarian diet should first do their own research to determine what’s best for their individual dog’s needs and/or consult their veterinarian.

“It just takes research and the willingness to stick by your reasons for having your dogs on a vegetarian diet,” says Benfer, who often makes homemade dog food for her three vegan dogs. “I get strange looks when I let people know my dogs are vegan, but it's only because they aren't educated about dogs being vegetarian and don’t realize how easy and possible it really is to do.”


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