Dog Supplements – Which Ones You Should Be Using And Why

Should you give your dog supplements?

Are you thinking of giving dog supplements to your best friend? Want to know if they’re safe and effective? Great! We’re going to delve into the world of vitamins and supplements to find out what works. Read on for more!

Why We Wonder About Supplements

We humans take vitamins and supplements for our health, right? So it’s totally natural to wonder if our canine pals would benefit from vitamin supplements for dogs. After all, anything we can do to help them live longer, happier lives is good. Their lifespans are so short as they are.

But the world of dog supplements is extensive, and it might seem a bit overwhelming. That’s why we’re here – to help you make sense of the options! Let’s start off by finding out if your dog needs a supplement.

Does My Dog Need A Supplement?

Plenty of pet parents give their dogs supplements. In 2006, a study found that about 10 percent of dog owners surveyed did so. Based on that study, the most commonly used are multivitamins, supplements for joint health (we discuss these in a separate article), and fatty acids. Antioxidants and probiotics are also popular.

Evidence suggests that today, the number of dogs taking supplements may now be as high as 35-40 percent. The numbers aren’t exact, because more research must be done. We don’t know much about the effectiveness or safety of dog supplements. We don’t have a lot of information on dosage, either. From brand to brand, there will be differences in the amount of active ingredients and quality. Some may help your dog; others may not.

What we do know is that many dog diets today are fortified to offer maximum nutrition. Most healthy dogs do not need additional supplements.

Are Supplements Safe for Dogs?

Dog supplements are regulated by the Federal Department of Agriculture, but only in a very limited way. Independent studies on safety for pets are rare. There’s a shortage of data, and therefore of rules and standardization in the industry. As with humans, having too much of a good thing can be dangerous. Overdoses of some vitamins can actually cause problems in dogs rather than solving them.

So the answer to this question is really unknown. We just don’t have enough information, and the variation in dog supplements is so large that we can’t generalize. If you still want to know more on the best dog supplements, read on for some specifics.

Calcium Supplements for Dogs

Calcium is a mineral that dogs need, but don’t necessarily get from meat. It is readily available in complete dog food diets, though. If a dog has a calcium deficiency, research shows that calcium supplementation is generally safe and effective. Still, you should know that too much calcium can cause problems. In part this is because it competes with magnesium and certain minerals for absorption in the intestine.

Excess calcium has been linked with the development of hip dysplasia, and should not be given to growing puppies, especially of large breeds. Also, it may increase the chance of getting bladder stones. As a result, calcium supplementation should only be done under the direction of a veterinarian.

Cranberry Supplements for Dogs

Cranberry dog supplements are usually used in cases of urinary tract infections, but research does not currently support the effectiveness for dogs.

In humans, studies show weak to no evidence that cranberry juice helps with urinary tract infections, and the variability in potency of over-the-counter products is an issue. If you want to try treating a UTI with cranberry, choose a cranberry extract with a high level of proanthocyadins. These are antioxidants that provide antibacterial effects.

Weight Gain Supplements for Dogs

In general, if you have an underweight dog, you need to find and treat the underlying cause of weight loss. First, you should start by modifying diet and exercise. Weight gain dog food supplements have variable ingredients in them, usually including a high amount of protein and healthy fats to help gain muscle mass. Sometimes they may include some kind of appetite enhancer, or vitamins and minerals to improve nutrition.

It’s hard to find scientific research to back up any benefits of weight gain dog supplements, though. Or any information at all, frankly! We do know that dogs get all the protein they need from food. High amounts of protein can cause problems with their bodily functions.

Liver Supplement for Dogs

Many people use liver supplements to reduce symptoms of liver disease in dogs. Liver supplements often include milk thistle, for the active ingredient silymarin (or silybinin). The very small amount of scientific evidence that exists for trials on companion animals indicates possible benefits and little harm. But we don’t yet know how to administer it for maximum effect.

Another supplement used for liver function is s-adenosylmethionine, or SAM-e. It’s supposed to raise glutathione levels for regeneration of liver cells. More research must be done to show that SAM-e oral supplementation works. A couple of studies only show there might be some possible advantages. However, many vets consider them effective, and will recommend and prescribe them for animals under their care.

Fatty Acid Supplements for Dogs

Available fatty acid supplements include omega 3 supplements for dogs and fish oil supplements for dogs. These are used to improve skin and hair health. They can reduce inflammation and are often prescribed for pets with dermatologic issues as good skin supplements for dogs or good dog coat supplements.

If your dog’s coat is healthy, that can reduce shedding, so fatty acid supplements are often also used as dog shedding supplements. They can reduce the intensity of allergies, which means that they may act as one of the possible dog supplements for itchy skin and dog supplements for dry skin, assuming allergies are the cause. Antioxidants may also help in these cases.

Fatty acids may assist in osteoarthritis, and fish oil is also used to assist in cardiovascular health as well. The anti-inflammation effects may help with kidney disease, so they are sometimes marketed as kidney supplements for dogs.

Studies seem to show that fatty acid supplementation can indeed improve skin health in dogs. However, there are associated drawbacks, such as increased lipid peroxidation (causing cell damage) and thinning of the blood.

The National Research Council says that 20-55 mg of EPA and DHA omega fatty acids together per pound of body fat is safe for dogs. But not enough research exists to specify what amounts are most effective. First, you need to understand the cause of your dog’s condition. Fatty acid supplements for dogs won’t necessarily be effective if the cause is an infection or disease.

Vitamin Supplements for Dogs

When it comes to optimal nutrition, there are plenty of options for dog food supplements. Adding extra good stuff to your dog’s diet seems like a no-brainer, right? Vitamins can improve body functions and be good allergy dog supplements by reducing reactions. But please know that supplements are no replacement for a proper, balanced diet.

In fact, without a nutritious diet, your dog might not be able to process supplements effectively at all. Additionally, most good-quality commercial dog foods are nutritionally balanced, meaning that adding multivitamins could actually lead to too many water-soluble vitamins and minerals. Excessive amounts of such vitamins can actually be detrimental to your dog’s health. Again, this is an area with limited research for canines.

Under some circumstances, however, nutritional supplements for dogs might not be a bad idea. Homemade and raw food diets often do not offer the right amounts of vitamins for your dog. Adding raw dog health supplements or dog supplements for homemade food here might assist in making sure pups get complete nutrition if you choose to eschew commercial diets.

Fiber Supplement for Dogs

Fiber supplements are generally designed to treat constipation, diarrhea, irritable bowel syndrome, and other gastrointestinal issues. They have been shown to combat obesity and diabetes, control symptoms of anal gland disease, and regulate the bacteria in the dog’s microbiome. Too much fiber can cause problems as well, such as diarrhea and nausea. Make sure your dog actually needs the fiber before you add it.

Do dog supplements help?

Iron Supplements for Dogs

Dogs can suffer from iron deficiency and anemia. Iron deficiency causes red blood cells to form abnormally. However, anemia can be caused by other things than iron deficiency; for example, it can come from a deficiency of certain B vitamins. Often, dogs with an iron deficiency are experiencing an underlying cause that must first be diagnosed before iron therapy can begin.

Additionally, iron-deficient dogs simply aren’t good at absorbing iron. Please visit a vet before adding any iron supplements to your dog’s diet.

Zinc Supplement for Dogs

Although zinc is an essential trace element that is needed by dogs for various tasks within the body, such as gene expression and cell operation, dogs often get enough of it in their meat sources. Zinc deficiency often appears as lesions on the skin in a condition called zinc-responsive dermatosis. Zinc can be used effectively, along with linoleic acid, as skin and coat supplements for dogs.

Too much zinc, however, causes a condition called zinc toxicosis. A study from 2010 found that, in 4,660 cases of zinc exposure in dogs called into the ASPCA Animal Poison Control Center, one of the main sources of zinc was multivitamins (others included pennies and batteries). Zinc poisoning can result in vomiting or death.

We do not recommend supplementing zinc unless your vet has established a regimen that includes a safe amount of a palatable type of zinc.

Supplements for Senior Dogs

As your dog ages, you may wish to provide senior dog supplements. Older dogs require more protein and less fat. Antioxidants can improve cognition and memory, and are good eye supplements for dogs. Glucosamine, fatty acids, fiber, and extra vitamins assist with other body functions.

If your dog isn’t getting enough of these from his food, you can ask a vet if supplements for older dogs containing these ingredients will help. One possibility would be protein supplements for dogs.

Enzyme Supplements for Dogs

Enzyme supplements are designed to support a dog’s digestion, and may be prescribed in cases of exocrine pancreatic insufficiency (EPI). This is another situation where current research doesn’t support the effectiveness of supplements. The underlying cause must be diagnosed and treated first. Some companies say dogs need these to make up for lacks in commercial diets, but this is not true.

How to Buy the Best Supplements for Dogs

Ultimately, here’s what we know generally about dog supplements. Some research exists about supplements for humans, but not enough. As for dogs, there are even fewer studies. Even in cases where studies have been done, we still may not know safe and effective dosages. Results may conflict with one another.

That doesn’t mean you should avoid all supplements; many vets may prescribe them to your dog and may have anecdotal evidence that they work just fine. Some, in the future, may become accepted therapies for the conditions we already use them for – once science has caught up with demand.

It does mean that you should absolutely get a vet’s point of view about what your dog needs in the way of supplementation. A sufficient diet should just about cover all your favorite pet’s needs. You can take other precautions, too.

The Labrador Handbook by Pippa Mattinson

Things to Do When Considering Dog Supplements

Check the quality of the products you’re buying. Know what you’re looking for and read labels. Do your research and find out more about the company. Does it specialize in one area? Has the product’s quality been verified by an independent organization? Some supplement companies have done internal studies that can show effectiveness in their products, and will provide them to you or medical professionals.

A good company will provide helpful information and be transparent about its practices. We absolutely understand the desire to help our beloved pets live longer and be healthier! Just do your research before you buy. Has this information been helpful? Let us know in the comments!

Dog Supplements – Which Ones You Should Be Using And Why

Resources and Further Reading

Becker, K. (2014). Zinc: You call it a trace mineral, but it could be fatal for your dog. Healthy Pets.
Ewing, P. Iron deficiency in dogs and cats. Massachusetts Society for the Prevention of Cruelty to Animals.
Food and Drug Administration, Federal Food, Drug, and Cosmetic Act.
Food and Drug Administration, Dietary supplements.
K9 Health Support, Whey protein.
Bauer, J. E. (2007). Responses of dogs to dietary omega-3 fatty acids. Journal of the American Veterinary Medical Association, 231(11).
Colombini, S. and Dunstan, R. W. Zinc-responsive dermatosis in northern-breed dogs: 17 cases (1990-1996). Journal of the American Veterinary Medical Association, 211(4).
Freeman, L. M. et al (2006). Disease prevalence among dogs and cats in the United States and Australia and proportions of dogs and cats that receive therapeutic diets or dietary supplements. Journal of the American Veterinary Medical Association, 229(4).
Gershoff, S. N. (1958). Adaptation to different calcium intakes in dogs. The Journal of Nutrition, 2(1).
Hackett, E. S. et al (2012). Milk thistle and its derivate compounds: A review of opporunities for treatment of liver disease. Journal of Veterinary Internal Medicine, 27(1).
Jepson, R. G. et al (2012). Cranberries for preventing urinary tract infection. Cochrane Database System Review, 10(CD001321).
Jewell, D. E. et al (200). Satiety reduces adiposity in dogs. Veterinary therapeutics: research in applied veterinary medicine 1(1).
Marsden, S., Calcium Supplements, VCA Hospitals.
Marsh, K. A. et al (2008). Effects of zinc and linoleic acid supplementation on the skin and coat quality of dogs receiving a complete and balanced diet. Veterinary Dermatology, 11(4).
Massimino, S. P. et al (1998). Fermentable dietary fiber increases GLP-1 secretion and improves glucose homeostasis despite increased intestinal glucose transport capacity in healthy dogs. The Journal of Nutrition, 128(10).
Medici, E. and Grigsby, L. (2013). Toxicology brief: Too much of a good thing: Zinc toxicosis in dogs. Veterinary Medicine: dvm360.
KcKenzie, B. (2011). The top ten pet supplements: do they work? Science-Based Medicine.
McKibbin, J. M. et al (1941). Studies on anemia in dogs due to pyridoxine deficiency. Journal of Biological Chemistry, 142.
Middlebos, I. S. et al (2010). Phylogenetic characterization of fecal microbial communities of dogs fed diets with or without supplemental dietary fiber using 454 pyrosequencing. PLOS ONE.
The National Academy of Sciences (2008). Safety of dietary supplements for horses, dogs, and cats.
Nutramax Laboratories Veterinary Sciences, Inc. Research articles for our products.
Piercy, R. et al (200). Effect of dietary supplements containing antioxidants on attenuation of muscle damage in exercising sled dogs. American Journal of Veterinary Research, 61(11).
Roush, J. K. et al (2010). Evaluation of the effects of dietary supplementation with fish oil omega-3 fatty acids on weight bearing in dogs with osteoarthritis. Journal of the American Veterinary Medical Association, 236(1).
Schoenmakers, I. et al. Effects of diets with different calcium and phosphorus contents on the skeletal development and blood chemistry of growing Great Danes. Veterinary Record, 147(23).
Wander, R. C. et al (1997). The ratio of dietary (n-6) to (n-3) fatty acids influences immune system function, eicosanoid metabolism, lipid peroxidation and vitamin # status in aged dogs. Journal of Nutrition, 127(6).
Weese, J. S. et al (2011). Antimicrobial use guidelines for treatment of urinary tract disease in dogs and cats: Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases. Veterinary Medicine International.
Westermarck, E. et al (1993). Effect of treatment on the jejunal and colonic bacterial flora of dogs with exocrine pancreatic insufficiency. Pancreas, 8(5).
White, S.D. et al (2001). Zinc-responsive dermatosis in dogs: 41 cases and literature review. Veterinary Dermatology, 12(2).
Zhao, X. T. et al (1996). Protein absorption depends on load-dependent inhibition of intestinal transit in dogs. The American Journal of Clinical Nutrition, 64(3).

The Labrador Site Founder

Pippa Mattinson is the best selling author of The Happy Puppy Handbook, the Labrador Handbook, Choosing The Perfect Puppy, and Total Recall.

She is also the founder of the Gundog Trust and the Dogsnet Online Training Program 

Pippa's online training courses were launched in 2019 and you can find the latest course dates on the Dogsnet website


  1. I am concerned about Chinese ingredients that can be found in supplements for dogs. Can you address this or publish an article about the practice of manufacturing vitamins and supplements using Chinese ingredients? I recently had my blood pressure medication recalled due to an ingredient from China causing contamination so am now concerned about supplements I buy for my dog. I think many vitamins manufactured in the US are using some Chinese ingredients and there is no way to tell from the ingredient list.