Are Supplements and Nutraceuticals Effective or a Gimmick? - The Most Common Mistakes Pet Parents Make (Part 3)

Dr. Shadi Ireifej discusses the importance of supplements and nutraceuticals - and what's fact and what's fiction. This is the third part of our series on "The Most Common Mistakes Pet Parents Make."


By Pet's Choice Supply. Featured Veterinarian,

Dr. Shadi Ireifej DVM DACVS
Co-founder and Chief Medical Officer at VetTriage


  Dr. Shadi Ireifej - Featured Veterinarian at Pet Pro Supply Co.

The Common Mistakes Pet Parents Make - Part 3

Supplements and "nutraceuticals" (nutrition pharmarceuticals) are very popular in the (human) medical and health industries. Most people have a cabinet drawer or shelf full of these products!

With so many of these products to choose from, and so much hype around so many of them, it's often hard for people to know what to believe. And, for diligent pet parents, the situation is the same: how do we know which products are actually effective, and most importantly, healthy for our pets?

This article aims to dispel myths around many popular pet supplements and nutraceuticals. In the case of each product, we ask: is there sufficient evidence showing that an individual pet benefits from a product that has so much doubt surrounding it - and should it be given every single day for the life of that pet?

Here we will break down two groups of supplements/nutraceuticals that addresses a specific disease for dogs, taking into account the most recent scientific literature and research on that particular product and its effects on that particular disease.


Glucosamine - a supplement to combat Osteoarthritis

Osteoarthritis (OA), also known as arthritis and degenerative joint disease (DJD), is a common, global, pathologic, ubiquitous, chronic, degenerative, and inflammatory joint disease. OA is characterized by lameness, stiffness, severe/chronic pain, disability, bone deterioration, and cartilage loss, with the final outcome being a failed joint and a decline in the quality of life for the animal. We are all familiar to varying extents as to what OA entails and why it’s a big deal, but when read out in medical terms, its wide spread incidence or debilitation become - unfortunately - much more obvious. You definitely do not want your dog to be afflicted with it!

Of all the supplements and nutraceuticals studied in veterinary medicine, perhaps the most extensively studied (and controversial) are joint supplements. Glucosamine hydrochloride and chondroitin sulfate are commonly recommended natural health products for treating OA in dogs. As common as this natural product is, the evidence supporting its use is limited and conflicting.

Glucosamine regulates the synthesis of collagen in cartilage and may provide mild anti-inflammatory effects while chondroitin sulfate inhibits destructive enzymes in joint fluid and cartilage. These two nutraceuticals also contribute to the synthesis of glycosaminoglycans and proteoglycans, which are cartilage-forming building blocks.

Let's look at some of the science:

A chondroitin dose of 15 to 30 mg/kg is typically suggested. It has also been suggested that 2 to 6 weeks of treatment with glucosamine and chondroitin may be necessary for any therapeutic effect to become apparent. Glucosamine sulfate administered intra-articularly and orally significantly reduces histological signs of OA, with the intra-articular application being more effective compared to oral administration. Potential adverse effects include hypersensitivity and minor gastrointestinal effects such as flatulence and stool softening.

A 2019 laboratory study using canine cartilage cells found that the joint supplement glucosamine significantly reduced the release of PGE2 and TNFα and was associated with reductions in cyclooxygenase-2 expression and nuclear factor-kappaB phosphorylation. This translates to decreasing inflammation on a cellular level. They concluded that supplements may have a beneficial role in preventing inflammation within the joint and that further studies are warranted.

A 2017 canine study comparing dogs undergoing orthopedic surgery with and without joint health supplementation found an improvement in lameness of treated dogs by a factor of 2.3 compared to non-treated dogs over 30 to 90 days' time. However, OA progression based on radiographs did not change. Aside from chondroitin sulfate and glucosamine hydrochloride, the studied supplement did contain anti-inflammatory and antioxidant ingredients which likely affected their results.

A study of working dogs and hip OA in 2017 compared the use of glucosamine, chondroitin sulphate, and hyaluronic acid to the use of a nonsteroidal anti-inflammatory drug (NSAID) alone. The oral joint supplement and NSAID produced some improvements in individual scores but where unable to do so when overall results were considered. They concluded that each of these options may not be able to, by itself, fully address the demands of a working dog with joint disease and related pain.

So, what's the upshot of all these studies? Should you give your pet joint supplements? The answer is a resounding yes. Despite the potential side effects, joint supplements such as glucosamine are an essential weapon in battling osteoarthritis, and as with so many things in pet health, an ounce of prevention is worth an ounce of cure. We highly recommend joint supplements.

If you're scientifically inclined, check out!/article/osteoarthritis-part-12 for an incredibly detailed document on osteoarthritis. Also, for for an educational video on osteoarthritis, check out Vet talks lets PAWS for a minute - Arthritis in my dog


Antioxidants for General Health

As of a few years ago antioxidants were all the rage for humans. "Drink green tea, it has antioxidants;" "blueberries are full of antioxidants;" "antioxidants are what keep you young!"

Let's take a look at the science behind how antioxidants actually help keep us (and our pets) healthy.

"Oxidative stress" is the overall production of reactive oxygen species that overwhelms antioxidant defenses, or is due to a loss of endogenous antioxidants. The result is damage to our cells and overall organisms. This is seen to occur in canine cases of gastic dilatation and volvulus (bloat), cardiac disease, and cancer (lymphoma and mammary carcinoma).

Components of oxidative stress include oxygen radicals, superoxide anions, hydroxyl radicals, hydroxyl anions, and hydrogen peroxide. Causes include lipid peroxidation, protein oxidation, and DNA damage, all of which are associated with chronic disease, carcinogenesis (cancer formation), and biological aging. Oxidative stress defense is via enzymatic stabilization, direct scavengers, and antioxidant treatment, amongst others.

What this means, in simple terms: oxidative stress is an outcome of disease and age, but we can help fight it by supplementing our pets' diets with antioxidant supplements.

There is ample scientific evidence for the benefits of antioxidants in pets:

A 2019 canine study used a combination-antioxidant supplementation for 30 days in systemically ill dogs. The supplementation included N-acetylcysteine/S-adenosylmethionine/silybin and vitamin E. In this population of systemically-ill hospitalized dogs, combination-antioxidant supplementation did not alter the antioxidant status, the degree of lipid peroxidation (a measurement of oxidative damage), clinical score and survival.

During a training course in 2019 for drug-detection dogs, dogs were compared with and without a daily nutritional supplement containing branched-chain and limiting amino acids, carnitine, vitamins, and octacosanol. Progression was documented with the use of heart rate monitors and blood samples. The dietary supplements accelerated heart rate recovery, showed the lowest concentrations of creatine kinase, aspartate aminotransferase and non-esterified fatty acids, suggesting a reduction in muscle damage and improvement of energy metabolism. These data suggest that this combined supplement can significantly enhance the physical fitness of drug detection dogs.

A 2019 study looked at the effect of a daily supplementation with a complex of vitamin E, zinc, selenium, folic acid, and n-3 polyunsaturated fatty acids on canine semen quality (semen motility and sperm membrane properties) over 90 days. They found that beginning at day 60 the supplementation significantly improved the total sperm count, progressive sperm motility, functional sperm membrane integrity, and decreased sperm mortality. Similar results were found in a 2018 canine study where the majority of sperm motility indicators and the percentage of normal sperm morphology and live spermatozoa increased significantly after 60 days of supplementation with selenium and vitamin E.

And finally, a 2018 study focused on the hypothesis that cognitive decline in aged dogs could be attenuated by dietary supplementation with a nutrient blend consisting of antioxidants, B vitamins, fish oil and l-arginine over a 6 month period of time. The supplemented dogs showed significantly better performance. These results suggest that the beneficial effects are positively linked to task complexity. Long-term supplementation can have cognition-improving effects and support the use of nutritional strategies in targeting brain aging-associated risk factors as an intervention to delay cognitive aging.

In sum: YES, give your dog antioxidant supplements! No dog is immune from aging and a myriad of diseases that can lead to oxidative stress. Give your dog the best weaponry in fighting their negative effects. Antioxidants are safe and very beneficial to overall pet health.




Pet supplementation is a complex topic, and science will continue to study it deeply, especially given supplements' broad commercial appeal. It's important to note also that no supplement alone is a panacea - and supplements' benefits are amplified when combined with other health-focused treatment options.

So, do for your pet's health exactly what you would do for your own. Maintain as healthy an overall lifestyle as possible! Eat a healthy diet, keep active, invest in preventable/prophylactic measures (like vaccinations and blood screenings), and take supplements and nutraceuticals - as recommended by your vet. 


Dr. Shadi Ireifej

About Dr. Shadi Ireifej:

Dr. Shadi Ireifej DVM DACVS is the Chief Medical Officer at VetTriage. He holds degrees from SUNY Binghamton and Cornell University and has practiced as a veterinary surgeon all across the United States. Follow him on Instagram @dr.shadi.ireifej and subscribe to his YouTube channel (Dr. Shadi Ireifej).


About VetTriage:

VetTriage is the world’s foremost provider of veterinary telehealth services. With VetTriage, pet owners have immediate access to triage advice from licensed veterinarians. Follow them on Instagram @vettriage and Facebook (