Some veterinarians believe glucosamine and chondroitin might be more beneficial to dogs as a preventive supplement, rather than for treating active disease. While certain supplements can have a place in joint disease management, some veterinarians are concerned about how they might be perceived by pet owners. "Supplements can play a large role in the management of joint disease and injury,” said Neal Sivula, DVM, Ph.D., FAAVA, vice president of the American Holistic Veterinary Medical Association and owner of Dancing Paws Animal Wellness Center in Richfield, Ohio. “They can speed healing and maintain joint health for those with chronic conditions. They work well alone for certain patients and combine well with traditional medication for those that require it.” “In our practice, we find that some clients may read about certain supplements online and come away with an inflated view of their potential for helping with joint issues,” Dr. Sivula said. Inflammation and tissue regeneration According to Lisa Weeth, BS, DVM, DACVN, owner of Weeth Nutrition Services based in Los Angeles, joint supplements mainly fall into two categories. “They may either help support and promote regeneration of joint tissue or can help decrease inflammation,” she said. “Glucosamine and chondroitin sulfate, at least in cell culture models, may help support normal cell regeneration. Supplements like fish oil help decrease inflammation at the level of the joint or cell.” A glucosamine and chondroitin sulfate combo is one of the more popular supplements used for joint pain, but its effectiveness is questioned by many specialists. “I would estimate that 80 percent of the clients who come to see me will tell me they are giving glucosamine and chondroitin,” said Sam Franklin, MS, DVM, PhD, DACVS, DACVSMR, of Colorado Canine Orthopedics and Rehab in Colorado Springs. “What I usually tell them is if they can afford to give glucosamine and chondroitin they can do so, but if they have to be more prudent about budgeting money for different things, there are other things for which I think there is better evidence. In my opinion, there’s not good evidence for oral glucosamine and chondroitin.” Dr. Weeth agreed, saying that for animals with active joint pain, most supplements are not going to be ideal. “The interventional studies that have looked at glucosamine and chondroitin supplements for dogs with arthritis, when you do the side-by-side comparisons, there is really no statistical difference between the placebo control and the interventional,” she said. “I think the response people see with glucosamine-chondroitin in individual dogs may be more of a placebo effect on the caregiver’s impression of activity, rather than an actual effect of the supplement itself.” That being said, Weeth noted the published studies were done on dogs with advanced joint disease, so they might not have much normal joint tissue to regenerate. She postulates glucosamine and chondroitin might be more beneficial as a preventive supplement, rather than for treating active disease. “Glucosamine and chondroitin may help support normal joint tissue,” she said. “Maybe we need to intervene earlier, when the dogs are young. Young active, athletic dogs—maybe those are the dogs that need to be on glucosamine. We just don’t have studies to show the ideal intervention time.” Supplements: Dosing, quality, and type When prescribing joint supplements, contact manufacturers to get the latest information regarding dosing. “The use of joint supplements has become popular enough that many professional continuing education meetings will have presentations covering their use,” said Neal Sivula, DVM, PhD, FAAVA, vice president of the American Holistic Veterinary Medical Association and owner of Dancing Paws Animal Wellness Center in Richfield, Ohio. “In addition, practitioner forums like the Veterinary Information Network can be a great source of information for those needing advice.” Dr. Sivula counsels clients that not all joint supplement products are created equal. “There is a broad spectrum of quality between products,” he said. “We recommend products that have been used in large numbers of pets and have been tested for quality. In general, you get what you pay for in quality.” Omega 3 fatty acids: Arguably the No. 1 joint supplement in terms of effectiveness, omega 3 fatty acids may reduce inflammation and can be given in supplement form, or more preferably, via a proven therapeutic joint diet. “We have used omega fatty acid supplements for over 15 years,” Sivula said. “In addition to their anti-inflammatory action in joints, we find them useful for skin issues, mental health, immune support, and eye issues. We counsel clients that quality and sourcing are very important in choosing an omega supplement.” Glucosamine and chondroitin sulfate: May support and/or promote regeneration of joint tissue. “As with all supplements, we caution owners that a reputable quality product must be chosen in order to have the best chance of a positive outcome,” Sivula said. Green-lipped mussel: A combination supplement that contains both glucosamine and chondroitin sulfate and omega 3 fatty acids. “It has some pretty good interventional studies,” Lisa Weeth, BS, DVM, DACVN, owner of Weeth Nutrition Services based in Los Angeles. “There are a lot companies that have looked at it and shown it’s been safe and not harmful for dogs.” Boswellia: An herbal supplement that may work to decrease inflammation. “The way this product seems to work, at least in the cell culture models, is it acts like a weak nonsteroidal,” Dr. Weeth said. “For me, this is where the safety question comes in, just like with any of our regulated concentrated nonsteroidals. We’re essentially giving the supplement to have a drug effect, but we don’t know what the side effects may be and we don’t know what the long-term implications of giving it every day may be.” Omega-3 fatty acids “Higher levels of omega 3s, when the omega 6 levels are controlled, increase the amount of omega 3 that gets incorporated into every cell in the body, and there is a statistically significant improvement in mobility and force plate and gait analysis in dogs and cats eating supplemented diets,” Weeth said. The problem with fatty acid supplementation is the ratio of omega 3 to omega 6 in the total diet needs to be controlled. Weeth once calculated the amount of fish oil one of her patients would have required to balance his low-fat, high-fiber diet, and it was a staggering quarter-cup of fish oil per day, which she does not recommend. “It’s hard to add enough fish oil on top of a diet to reach the therapeutic levels that were done in clinical trials,” Weeth said. “A typical over-the-counter dog food has an omega 6 to omega 3 ratio anywhere from 3:1 to 30:1. If your base diet is a 30:1 omega 6 to omega 3, that’s a lot of fish oil you have to add in. The dog is going to get diarrhea or probably break with pancreatitis before you hit the therapeutic dose.” Enter therapeutic joint diets. Delivering fatty acids via a therapeutic joint diet is easier and more effective than attempting to supplement with fish oil because the diet developed from the very beginning with the ideal omega 6 to omega 3 ratio (somewhere around 2:1, according to Weeth). This means they are able to achieve a much higher level of omega 3 relative to the other fats. At least two of the commercially available veterinary therapeutic diets have the science to back them up. “There is some evidence now for a couple of the joint specific diets,” Dr. Franklin said. “There are studies done in dogs with OA that have not had surgery and then there are some more recent studies looking at dogs that had surgery for CCL disease. Those studies offer some evidence of benefit.” Using a therapeutic joint diet versus fatty acid supplements is especially important with cats. “With cats you have to be careful with omega 3,” Weeth said. “Very high doses have been associated with platelet abnormalities and bleeding disorders in cats. Increasing the omega 3 intake also increases the requirement for vitamin E in the diet. Therapeutic diets are actually safer from a feline medicine perspective, rather than trying to supplement on top of a commercial food.” Fourfold priorities Franklin might consider joint supplements to manage a dog with osteoarthritis nonoperatively; however, his main priorities are fourfold: getting the dog to an optimal body weight, introducing moderate daily exercise (preferably low or minimal impact), implementing optimal nutrition, and prescribing nonsteroidal anti-inflammatories. “Joint supplements could be considered while those other four things are being met, but I try and emphasize to owners, as well as students and other veterinarians, that these big four are probably the most important,” Franklin said. “It certainly doesn’t seem to be very rewarding when the dog comes in and it’s overweight, it doesn’t exercise, it’s not on an appropriate diet, it’s not getting a nonsteroidal anti-inflammatory, and it’s getting a joint supplement. That’s not a recipe for success.”
