Warning: Spaghetti is not one of the 5 human foods to feed your dog (but it's a really cute picture). (Corbis Images)

Most of the time, pet owners are cautioned to never feed their furry friends "people food." Veterinarians often remind pet owners that chocolate, grapes, and raisins can be poison to dogs and cats and that onions can cause a life-threatening form of anemia. And while broccoli, cauliflower, and other vegetables in the brassica family (cruciferous vegetables) can be healthy additions to diet, but can have a troublesome affect on thyroid function unless they're cooked before feeding.

But there are human foods that, when used as a supplement to a dog or cat's diet, can be quite beneficial to their health. Our pets have thrived on our leftovers for hundreds of years, but with increasingly unhealthy diet choices in human meals, we need to be careful what we offer our pets from our own plates.

Human foods such as meats, fish, cheeses, and other animal products can be used regularly in a healthy pet's diet. We just have to be sensible about what we feed, and, of course, how much.

So what should you skip? Avoid feeding your pet any corn, wheat, soy, or peanut butter in food or treats. Be aware that glutens, spelt, maize, breads, corn syrups, and pasta are other names for wheat and corn products.

What You Should Really Be Feeding Your Pet

Dogs who have "sensitive stomachs" may just need a healthier diet of fresher foods. The GI tract depends on a large amount of appropriate bacteria to function properly, and to decrease gas and improve stool consistency. Because the foods we feed our pets tend to be so carefully packaged to avoid bacterial pathogens, it may be difficult for animals to obtain proper bacteria for their gastrointestinal tract. A periodic probiotic supplement or some yogurt (and if you can find it, goat yogurt is even better than cow yogurt) can help re-populate the GI tract and improve digestive health.

Other over-the-counter probiotics can be used as a pet supplements as well. Dairy-free versions are available for sensitive animals. Just remember to look for well-sourced organic products from respected companies.

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Aside from the occasional meat treat or healthy leftover, here are five additional foods that you should be feed your pet, and why they're good for your furry friend.

Unsweetened Canned Pumpkin

For a Superman-strength stool regulator, give your dog or cat a bit of pumpkin. It regulates moisture and provides a gentle fiber, making it a terrific tool to combat constipation or diarrhea. Dosage is 1 tablespoon once or twice daily for a 30-pound dog or a 1/2 teaspoon for an average cat, in food or as a treat. I'm surprised at how many cats like to eat straight pumpkin from a spoon, but you also can mix pumpkin with meat, baby food or yogurt.

Fun idea: Put the pumpkin or pumpkin mixes (with yogurt, meat baby foods or other meat-based treats) into ice cube trays or in rubber toys, or in spoonfuls on wax paper and freeze to use later as treats. This also solves the problem of open cans of pumpkin from going bad in your fridge.

Fish Oil

Omega-3 fatty acids such as fish oil aren't just good for humans, they can improve your pet's coat and him recover from inflammatory conditions, arthritis, and skin problems. How? Omegas encourage free-radical scavenging, which can decrease inflammation. But take note: Carnivores do not efficiently convert plant sources of omegas, like flaxseed or hemp, so stick with fish oils.

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I personally believe pet owners should avoid feeding their animals krill oil (which is derived from small crustraceans usually found in the Arctic and Antarctic seas), since it's the only thing whales eat, so let's not be cruel and take it away. While Omegas are usually a helpful supplement, they're not for all pets. Fish oil may not be recommended for an animal that is overly hot, and has oily/hot skin or loose stools. If you're giving your pet Omegas, be sure to monitor the response to see if they're right for your animal.

Psyllium Fiber

Many foods, including many raw foods, may not include enough fiber. Typically a scavenger or carnivore would eat a good deal of fiber – including roughage like hair, feathers, and nails. And those are not typical ingredients in pet foods. Adding psyllium fiber (about a teaspoon per meal for a 50-pound dog or a 1/4 teaspoon for an average cat) is a great way to improve the fiber content of the food. Derived from the husks of seeds in the Plantago family, Psyllium fiber contains a high level of soluble dietary fiber. It can be found in most supplement sections of your local drugstore or supermarket. Fiber moving through the GI tract can be used to improve symptoms of both loose stool and constipation, and may even enhance the ability to fight off GI parasites.

White Rice

Cooked white rice can relieve signs of diarrhea. But how you prepare it can really make a difference. Cook the white rice with extra water and overcook until it is gloopy. Your pet's system can absorb it better when it's overcooked and sticky-wet. The reason it works is because of its absorbent quality, not its nutritive value, which is why brown rice is not as effective for diarrhea and loose stools. But do not use Minute Rice; all the good absorbent stuff has been processed out of it.

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Chicken or Beef Broth

Warm, low sodium chicken or beef broth — or even plain warm water — can be added to pet food to increase palatability. The meat broth itself can enhance the flavor of foods, and foods smell more appetizing when they are warmed. In addition, if you're concerned about hydration, pets will drink more fluids if the fluids taste good.

Barbara Royal is a veterinarian in Chicago who is internationally renowned for her work in integrative medicine and physical rehabilitation. She is the author of "The Royal Treatment: A Natural Approach to Wildly Healthy Pets" and the go-to veterinarian for Oprah Winfrey. Dr. Royal currently is president of the American Holistic Veterinary Medical Association and president-elect of the AHVM Foundation. She also is the founder and owner of The Royal Treatment Veterinary Center in Chicago.

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