Recently there have been many ads on social media regarding nutritional supplements to treat arthritis, or what are commonly called nutraceuticals. In following many dog owners’ comments about these products, it raised many questions about how people perceive these products versus the reality of the benefits these products provide. I am probably going to stir up some controversy and hit some raw nerves, but I feel obligated to tell the truth and educate people so that their dogs can have the best possible quality of life.
First, what are nutraceuticals? These products are nutritional supplements, and at least in the United States (and many other countries), they may be purchased over the counter without a prescription. However, some products may only be purchased from veterinarians, despite not requiring a prescription. Nutritional supplements are regulated by the FDA in the US, but they are not required to have the rigorous testing that drugs must undergo, including toxicity testing, dose titration studies, or efficacy studies. They must contain wording to the effect that these products are not intended to diagnose, treat, or cure conditions, but they may support certain body systems. For our interests, this is joint health. Any suggestion that they can turn crippled dogs barely able to walk, into young playful dogs, is misleading at best, and illegal at worst. But unfortunately, many questionable companies prey on owner’s hearts, giving false hope and promises, and potentially delaying or preventing treatments that are actually beneficial. Are all nutritional supplement companies unreputable? Certainly not. And these products do have a place, in my opinion, but it is heart-breaking to see so many dog owners purchase some of these products, hoping for a miracle. A basic rule in life is that if it sounds too good to be true, it probably is.
How should dog owners evaluate these products? There are numerous issues with the quality of some products. Multiple studies have shown that if products are purchased from stores and analyzed in an independent laboratory, 25-35% of the products have no or little active ingredient in the product. Essentially, you are purchasing a placebo in many cases. How is this possible if they are regulated by the FDA? Some years ago I had a conversation with a person in government, and when I posed this question, they admitted that there is just not enough manpower to police the industry. Some unscrupulous companies may be in business for a brief time, face regulatory issues, close that company, and then immediately open another company. Almost like a shell game. What about products that have guaranteed purity of raw ingredients? While this may be true at the point of origin, there is no guarantee that this is the product that is actually shipped, or that the ingredient makes its way into the final product. Only purchase products that have undergone independent testing by outside laboratories. One service that evaluates many human products and some animal products is consumerlabs.com. There is a yearly fee to subscribe, and they do not test all products, but they will tell you the results of the products that test well. Weigh the benefit of finding if a product has tested well versus spending money on a placebo.
Let’s talk about the efficacy of these products. If the only thing the company touts is owner testimonials, run as fast as you can from those products. Marketers love to tug on dog owner’s hearts about how a dog that could barely walk, can now run and play after taking their product. Only buy products that have undergone blinded, randomized, prospective placebo-controlled studies with adequate outcome measures, such as force plate evaluation of weight bearing while walking or trotting. What does all this mean? It means that the product and a placebo should be given to dogs, using random assignment to dogs so there is no selection bias of which dogs receive which treatment. The study should be done prospectively, which means that the data are not generated after the fact, but are collected as part of a proper study design. Study personnel and owners should not know which treatment a dog has received until the end of the study to avoid bias in assigning any subjective scores, such as level of pain or lameness. Better yet, objective data, such as weight bearing forces placed on limbs while walking or trotting over a force plate, is best. These types of studies can be costly, often $200,000-500,000, and most companies will never risk these studies because many of the products would be no better than placebo in all likelihood. Independent studies that have been done without corporate funding are even more impressive. Companies with products that have been studied should go to the top of your list, even if they cost more, because they have shown that they actually may work as opposed to putting their money in slick marketing.
Let’s talk a little further about efficacy of nutritional supplements versus other treatments, such as nonsteroidal anti-inflammatory drugs, or NSAIDs. I believe many people turn to nutritional supplements because they have experienced or heard of serious side effects of an NSAID. It is true that as with any drug, an individual dog may have a side effect, sometimes very serious. But properly used (not combining an NSAID with another NSAID, including aspirin, or a steroid, using the proper dose based on weight, and carefully monitoring the dog, including periodic blood work), these drugs are still safe. If a dog has a side effect with one NSAID, it doesn’t mean that they will have a side effect with another; they may tolerate another NSAID better. What do studies show about the effectiveness of NSAIDs for osteoarthritis? Remember the FDA requires toxicity, dose titration, and efficacy studies, usually with a placebo control or sometimes as a comparison to a similar drug, and the studies are carefully monitored. Most NSAIDs have an average 2-8% improvement in force placed on the affected limb using objective force plate analysis of gait, and generally 80-90% of patients have a positive response to treatment. The interesting thing is that 25-60% of placebo patients can have a positive response in some of the outcome measures! How can this be? Think about it. Dogs (and people) do not have a constant amount of pain – it waxes and wanes based on the activity level, weather, and many other variables. These positive responses are simply part of the up and down nature of osteoarthritis. This is why having randomized placebo controlled studies is so important. If a treatment (any treatment) for arthritis claims to help around 50% of patients, it may be placebo effect. The treatment should at least be better than the placebo. Another thing to consider about companies that offer testimonials without proper studies. Remember that proper studies usually have a pretreatment phase and generally require dogs to have a consistent amount of exercise, constant diet, and be free of other arthritic treatments to ensure that the level of lameness is stable before beginning the study and other things do not contribute to improvement, such as weight loss. When do you bring your dog to the veterinarian? When it is doing well, or when it is painful and lame? Most dogs will spontaneously improve (to some extent) with rest, self-restriction, and resolution of inflammation brought on by excessive play in many cases. So no matter what treatment is given, most dogs will improve within a few days. So we should not pat ourselves on the back that whatever supplement or treatment was given was responsible for the improvement. Also, many times, the supplement is given with other treatments, such as an NSAID or other pain medication.
So, what nutritional treatments are available? Certainly the cheapest and most effective nutritional treatment is weight loss! It is really sad to see so many overweight limping dogs. Save money on treatments, dog food, and increase how long your dog lives with simple weight loss. Omega-3 fatty acids, or fish oils, also have value in treating osteoarthritis and this has been demonstrated in a number of prospective placebo controlled studies. Other nutritional supplements that are available include glucosamine, chondroitin, avocado-soybean unsaponifiables, undenatured type II collagen, green lipped mussel, Boswellia, green tea, turmeric, methylsulfonomethane (MSM), S-adenosylmethionine (SAM-e), egg shell membrane, elk velvet antler, hyperimmune milk, pycnogenol, CBD oil, and many others. Unfortunately, very few studies, if any, are available for most of these supplements in dogs. In cases where studies are not available in dogs, we rely on studies of humans. But dogs are not people. Many of these supplements have studies done in cell cultures of cartilage cells to look at potential mechanisms of action, but it is a huge step going from very controlled conditions in a petri dish to the complex joint organ.
What to look for in using a supplement? The first thing is, are there adequate controlled studies to evaluate the ingredients I am interested in using? Has the particular product been independently evaluated for product content by an outside laboratory? Does the product follow good manufacturing processes? Does the product have the NASC (National Animal Supplement Council) quality seal? What is the product cost versus clinical benefit of the product? Does it have an effect on my dog? I would classify nutritional supplements as helpful in some dogs, but not in others. So if a product seems to work in your dog, then continue it. If not, then discontinue it and save some money. However, if you stop a product, watch what happens over the next 2-3 weeks. In some cases, improvement is so gradual, you may not appreciate it. But when you stop the product, things may suddenly worsen.
What do I recommend? Supplements that I often recommend are omega-3 fatty acids, avocado soybean unsaponifiables (with glucosamine and chondroitin in the product), Boswellia (if it is already contained within a product), undenatured type II collagen, and turmeric. I should point out that while there may be clinical improvement with the product(s), I am really hoping to alter the environment of the joint and hopefully slow the progression of the arthritis. There is some evidence of this in people, but we will likely never see such studies in dogs because of the cost, large number of patients necessary for such studies, and the long term nature of such studies. The dogs I usually see are in the middle to late stages of arthritis, so an NSAID is usually needed for pain and inflammation. But if we are fortunate to treat in the early stages, nutritional supplements, exercise, weight control, and injectable polysulfated glycosaminoglycans are a reasonable strategy until additional treatments are needed.
Hopefully this will provide you with information to better care for your arthritic dog. And save some money.