Pets have it easy. They'll never know the willpower it takes to pass up the dessert tray. On the other hand, they'll never know the thrill of enjoying a trendy new diet, either. Most are stuck with plain old pet food—and, as we're discovering with the rise of the raw-food craze for pets, maybe that's the way it should be.

We all want what's best for our pets, and today that seems to mean a diet of fresh fruit, vegetables, and meat. At least that's how raw-food devotees see it. They say that raw foods are the secret to shining coats, stronger teeth, and higher energy levels. You might even feel guilty if you're not serving your four-legged pal an amped-up doggie version of the Paleo diet. But before changing over to uncooked, unprocessed food—we're not talking table scraps here; we're talking raw beef, chicken, and eggs—you should know that doing so carries risk.

Dogs aren't wolves; cats aren't lions.  A raw, meaty diet intuitively seems like a smart, natural choice for dogs and cats, right? Actually, today's pets resemble their ancient ancestors about as much as we resemble Neanderthals, nutritionally speaking. Our dogs are genetically better suited to a starchier diet than wolves are, says research published in Nature.

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More to the point, serving up raw animal protein puts your pet—and household—at the mercy of Salmonella, Listeria, and other disease-causing microbes that those foods can carry, concur leading experts from the CDC and the American Veterinary Medical Association. So, though your canine or feline is less likely to fall ill from those bugs than you are, the urge to fill your dog's dish with raw meat isn't ultimately wise. What your dog or cat needs is pet food labeled "complete and balanced" by the Association of American Feed Control Officials, a consumer protection agency. That label means that the food satisfies 100% of your pet's dietary requirements, says Ann Hohenhaus, a staff doctor at the Animal Medical Center in New York City.

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Think veggie treats. Giving your dog raw produce as an occasional treat is a smart move. Fiber- and nutrient-rich fruits and vegetables stimulate gums and can be great low-calorie alternatives to processed treats. "Cap fruit, vegetable, and snack intake at 10% of your pet's caloric requirements," Hohenhaus says.

Apple, pear, and carrot slices are good options, as are broccoli and green beans, says Joseph J. Wakshlag, a diplomate of the American College of Veterinary Nutrition and an associate professor of clinical nutrition at Cornell University's College of Veterinary Medicine. Avoid these: grapes and raisins, which can cause serious kidney damage, and garlic and onions, which can harm animals' red blood cells.

"Cats can eat vegetables, but most aren't wild about them," Hohenhaus says. Some, however, do enjoy "kitty grass," which is sold in grow trays at pet stores.

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When raw isn't wrong. To every rule is the exception: Some pets with chronic health issues may do better on a raw diet than on processed foods. Your vet can best determine whether your pet needs to go the raw route and will advise you on what to do. He'll almost certainly suggest ready-made raw food from your pet store's refrigerated or frozen section—it's more likely to be complete and balanced and processed by high-tech alternatives such as high-pressure processing, which kills bacteria. Make sure that the process noted on the back label is listed on the FDA's Alternative Food Processing Technologies page; if it isn't, contact the company to find out about their quality-control and processing technologies, Wakshlag says. Costwise, ready-made raw is more expensive (but less time intensive) than a homemade raw regimen and about four times pricier than dry food and twice as much as traditional canned options.

Still, if you choose to foray into the world of raw food to solve your pet's health problem, do it gradually. Just like ours, animals' digestive systems need time to adjust to dietary changes. Wakshlag recommends a simple quarter system—replace a quarter of your cat's or dog's regular food with the new fare the first day, half the next, and three-quarters the next. Worst-case scenario, a softer stool may result, but the gastrointestinal tract should get used to the new food in a few days, giving the raw craze its one opportunity to do some good.

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