Do Our Pets Really Benefit from Supplements? Here’s What the Experts Have to Say

This post first appeared on

Our late Rottweiler mix, Lucy, was diagnosed with chronic hip dysplasia when she was only 4 years old. After researching ways to help her I learned that joint supplements containing the ingredients chondroitin and glucosamine seem to help some dogs with joint issues. Following a discussion with my veterinarian, I started Lucy on two pills a day. I don’t know if they helped her, but she joined us on walks and hikes until we finally lost her at age 15.

Joint supplements containing the ingredients chondroitin and glucosamine seem to help Lucy who had chronic hip dysplasia. 

Now we think that our 10-year-old border collie mix, Jason, is showing signs of arthritis. Once the vet confirms this, we’ll ask if we should put him on the same supplements we used for Lucy? We’re not alone in considering the use of pet supplements. According to market researcher Packaged Facts, projected retail sales for pet supplements and nutraceutical treats in the U.S. are expected to grow through 2017, to an estimated $1.6 billion.

The National Animal Supplement Council (NASC) describes pet supplements as products that are intended to complement the diet and help support and maintain a normal biological function. Products range from multivitamins for overall health to targeted formulas that claim to alleviate joint problems or canine cognitive dysfunction.

Do Our Pets Really Benefit From the Addition of Supplements in Their Diets?

The most commonly used pet supplements are multivitamins, joint supplements and fatty acids. Veterinary experts agree that glucosamine/chondroitin supplements if they are of good quality, may have modest benefits in some animals with arthritis. And fish oil supplements may be beneficial for pets with certain medical conditions, such as heart disease, kidney disease and cancer. However, even these common supplements have potential side effects and are not right for every dog and cat with these conditions. As for multivitamin supplements, veterinary experts say that pets do not need these unless they are on a nutritionally unbalanced diet.

“A healthy dog and cat on a well-regulated commercial pet food that has been carefully designed by a board-certified veterinary nutritionist will be getting all the vitamins and minerals they need,” said Laura Eirmann, a veterinary nutritionist at Oradell Animal Hospital. Complete and balanced pet foods are made to give pets the right amount of nutrients and adding more could be harmful to your pet Eirmann said. For example, giving too much calcium to a large breed puppy can lead to skeletal diseases.

Speak with Your Veterinarian before Adding a Supplement to Your Pet’s Diet
Eirmann advises that pet owners always speak with their primary care veterinarian before adding a supplement to their pet’s diet. This is especially important because unlike drugs, the Food and Drug Administration (FDA) does not review supplements for efficacy, safety or quality before they are put on the market. Drug manufacturers must prove that a drug is safe and effective before it can be sold to consumers. However, in the case of pet supplements, the FDA has to prove that they are unsafe before they can be pulled off of the market.

Image credit: Thinkstock

“Because pet supplements are not regulated it’s a buyer beware area,” Eirmann said.

“Dogs and cats handle food items differently than we do. Just because a supplement is advertised as natural, that doesn’t mean it is safe for our pets.”

In her article “Dietary Supplements for Pets: Harmful or Helpful?” Lisa M. Freeman, a veterinary nutritionist, and professor at Tuft’s University Cummings Veterinary Medical Center wrote that pets can get sick or even die as a result of dietary supplements. She writes:

“Even if the supplement by itself is safe, its use in combination with medications an animal may be taking can cause dangerous interactions. In addition, numerous studies have shown that many supplements have terrible quality control. This means that if you buy a supplement that is supposed to contain 500 mg per tablet, it may contain 500 mg but it also may contain 1000 mg or nothing at all! Some supplements may be contaminated with mercury, lead, or other substances. That doesn’t even get into the issues of supplement tablets that don’t dissolve appropriately (which means they won’t get absorbed).”

Eirmann said there is evidence that some supplements can help pets. In fact, her 15½ -year-old golden retriever, Sprocket, is taking a supplement that contains SAMe and Silybin, proven to support certain types of liver disease. In addition to speaking with a veterinarian, Eirmann’s advice to anyone interested in adding supplements to their pet’s diet is to do extensive research. Find out if the company manufacturing the supplements has done any studies and if those studies are applicable to your particular pet.

“If you’re doing the research online, don’t rely solely on testimonials or company marketing materials,” Eirmann said. “You want to know if a product is safe and if it is effective. Your veterinarian is the expert so ask before making a final decision on using a product.”

Where to turn for more information on pet dietary supplements and pet food:

Source: Laura Eirmann, a veterinary nutritionist at Oradell Animal Hospital