What Are Dog Supplements and How Do They Work?

Laura Russell, DVM, MBA, DABVP
By Laura Russell, DVM, MBA, DABVP on Sep. 6, 2023
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The market for dog supplements has increased exponentially over the past several years. Pet parents want to do everything they can to ensure their pets have happy, healthy lives.

 For many dogs on an AAFCO-approved diet, supplements are not necessary. However, dogs that have medical conditions or who are predisposed to developing them can benefit from supplements.

It’s always important to discuss supplement recommendations with your veterinarian prior to adding a supplement to your dog’s diet. Your vet will help you find a product that fits your dog’s health needs.

What Are Dog Supplements?

Supplements are defined as any product added to a pet’s regular diet that contains ingredients intended to improve health. The National Animal Supplement Council (NASC) is a nonprofit industry group that awards a seal to manufacturers who meet the council’s standards. The organization offers an NASC Quality System to ensure safe, effective, and high-quality products. When searching for a supplement, look for the NASC seal to ensure it has met the standard.

Scientific research has studied many common ingredients of supplements, and your veterinarian is the best resource to help sort out products that may be helpful to your dog and their health conditions. While none are magic bullets, many supplements may be helpful in slowing the progression of disease or supporting your dog’s body to prevent illness.

Why Do Veterinarians Recommend Supplements?

Supplements are often recommended by veterinarians to enhance other prescribed therapies or potentially prevent health issues, such as arthritis, from progressing. In the case of fatty acid supplements, dogs with heart disease or puppies at risk of developing heart disease may benefit from having more of these nutrients in their system.

While a well-balanced diet is the cornerstone to nutrition, supplements can help to augment the nutrients available. Some homemade diets are not reviewed or balanced by a veterinarian or nutritionist, and they often need added supplements to ensure the correct vitamin and mineral ratios are met. 

Since these diets tend to be unbalanced, a veterinarian or veterinary nutritionist should ensure the dog’s diet is complete. Vets may offer supplements as a way to help support the nutrients that are missing in these diets.

How Supplements Work for Dogs

Supplements work by adding nutrients to the diet; for some dogs, having more nutrients available to them may help to reduce or prevent some illnesses. Puppies have different requirements than adult dogs due to their growing bodies, and senior dogs often have health conditions that supplements can help treat.

Common Ingredients in Dog Supplements

Glucosamine and Chondroitin

Glucosamine and chondroitin are common ingredients in many joint supplements and make up a compound typically found in cartilage. Supplements with these ingredients can help joint cartilage stay healthy or heal and support the fluid lubricating the joints. Glucosamine and chondroitin may be recommended for dogs with hip dysplasia, osteoarthritis, cartilage damage, or loose joints.

Keep in mind that glucosamine must be used long-term to see any beneficial effects and won’t treat the pain of arthritis in dogs or joint issues in dogs. Work with your veterinarian to determine the best inclusion of both a joint supplement and pain medication, if needed, depending on your dog’s health.

Antioxidant Supplements for Dogs

Antioxidants are substances that protect cells from free radicals (molecules that circulate in the body). Antioxidants can reduce inflammation, prevent disease, and help support the body during natural aging.

Fish Oil Supplements for Dogs

Fish oils are omega 3 fatty acids, antioxidants that can improve coat and skin health, support the muscles of the heart, and help with brain development.

Probiotic Supplements for Dogs

Probiotics are microorganisms that are beneficial to a body’s normal health processes.  Probiotics help rebalance the flora in the gastrointestinal tract to help heal after illness or to maintain good flora levels in pets predisposed to disease causing chronic diarrhea or inability to absorb nutrients. Many times, probiotics are used during or after antibiotic therapy to replace some of the “good” organisms that can be collateral damage with antibiotic use. 

Liver Supplements for Dogs

S-adenosylmethionine (SAM-e) is a common liver support supplement that mimics glutathione, a compound made by the body that is used to detoxify and protect the liver. Liver supplements are often recommended for toxin ingestion, gallbladder disease, or hepatitis.

Talk to Your Veterinarian About Supplements

Always talk with your veterinarian before giving your dog any supplement. Never give human supplements to your pet without checking with a veterinarian, as the dosage ranges can be different and could lead to a toxic reaction in your dog. Calcium, vitamin D, and iron can all build up to unsafe levels in your dog’s body if supplements are given at incorrect doses. Many human products also contain xylitol, which is a sweetener toxic to dogs.

Supplements are also not a substitute for your pet’s prescription medication—never stop giving a prescribed drug without your vet’s approval. Your vet is the best source for information and recommendations when it comes to finding the best supplement for your dog’s needs.

Featured Image: iStock.com/StockRocket

Laura Russell, DVM, MBA, DABVP


Laura Russell, DVM, MBA, DABVP


Dr. Russell is a 2003 graduate of the University of Missouri. She is board certified in Canine and Feline Practice, certified in canine...

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