The Power of Vitamin C for Dogs: Benefits and Sources

Can dogs eat it

The Can Dogs Eat It Team

The Power of Vitamin C for Dogs: Benefits and Sources
Reading Time: 7 minutes

joana garridoReviewed By Joana Garrido DVM

Unlike humans, dogs naturally produce vitamin C in their bodies. However, their ability to synthesize this nutrient can become compromised due to illness or constant exposure to stressors.

As you read on, you will learn when is the best time to provide vitamin C supplementation to your dog and know the type of vitamin C most suitable for him.

What Is Vitamin C for Dogs?

vitamin c rich orangesVitamin C also called ascorbic acid functions as an antioxidant that rids dogs’ bodies of free radicals. Free radicals are molecular compounds that wreak havoc in the canine system and contribute to the development of diseases.

Vitamin C for dogs is a water-soluble nutrient. This means it can disperse in water and then be distributed and easily absorbed into the body tissues.

Health Benefits of Vitamin C for Dogs

Vitamin C has potent antioxidative powers that provide a bunch of health perks to Fido including:

1. Strengthening the Immune System Response

Vitamin C plays a role in supporting the immune system in moderate doses. However, it’s important to note that higher doses of vitamin C can have pro-oxidant effects, which may promote cellular oxidation and lead to cell deterioration.

While some pet owners believe that vitamin C supplementation can help prevent cancer, bladder stones, and other ailments in their pets, scientific studies have not confirmed these claims for cats or dogs.

It’s crucial to strike a balance and ensure your pet receives a well-rounded diet that includes natural antioxidants from fruits and vegetables. This approach provides healthy antioxidants without the potential risks associated with excessive vitamin C supplementation.

2. Promoting Tissue Creation and Repair

Vitamin C for dogs plays an integral part in collagen synthesis, which supports healthy bone development and strong joints. Supplementation of vitamin C can also help prevent or ease orthopedic issues.

For instance, a 2013 study shows that using hyaluronic acid in combination with vitamin C was effective in treating first-stage hypertrophic osteodystrophy, which is a developmental, auto-inflammatory disease of the bones.

3. Hastening the Recovery from Ailments

Recent research in veterinary literature has shown limited studies on vitamin C levels and supplementation in sick dogs. However, several uncontrolled trials have reported positive outcomes when dogs with conditions like canine distemper, hypertrophic osteodystrophy, hip dysplasia, sarcoptic mange, leishmaniosis, hemolytic anemias, and gastric dilatation-volvulus were given vitamin C supplements.

These findings indicate that vitamin C supplementation may offer potential benefits in treating these diseases in dogs. For more information, please refer to the latest research paper on this subject.

The antioxidant properties of vitamin C could be the reason behind its positive effect on dogs with ailments. It offers immune support, which quickens recovery.

Do Dogs Need Vitamin C Supplementation?

vitamin c supplementsHealthy dogs do not need vitamin C supplementation because they naturally synthesize this nutrient in their liver.

Canines that can benefit from vitamin C supplementation the most are those with vitamin C deficiencies brought on by ailments like liver disease.

Do note that exposure to various physical and emotional stressors can affect vitamin C production in dogs such as:

  • Vaccinations
  • Demanding canine work
  • Lactation
  • Sudden relocation
  • Weaning

To avoid depletion of vitamin C, supplementation may be recommended for dogs facing any of these situations.

Signs of Vitamin C Deficiency in Dogs

vitamin c tablets for dogsCanines producing insufficient levels of vitamin C in their body usually exhibit the following symptoms:

  • Lethargy
  • Weakened bones and muscles
  • Slow wound healing
  • Painful joints
  • Bleeding gums

If you suspect that your dog has developed this condition, take him to the vet for a proper diagnosis. Blood tests will be carried out to check if your dog has vitamin C deficiency or is prone to physical and mental stress.

If the result is either of the two, the vet may suggest giving your dog vitamin C supplements to mitigate the side effects of their condition.

Natural Sources of Vitamin C for Dogs

natural vitamin c for dogsMost dog food contains sufficient amounts of vitamin C. However, it might not be enough for vitamin C-deficient dogs.

If you are looking for a healthier way to increase your dog’s vitamin C consumption, incorporating vitamin C-rich fresh food is a good idea.

Here is a list of dog-friendly food with high vitamin C content:


Before making any changes to your dog’s diet, discuss your plan with the vet. They will determine if it is appropriate and beneficial for your dog’s health.

5 Different Forms of Vitamin C Supplements for Dogs

vitamin c for dogsVitamin C supplements come in multiple forms with different absorption rates and acidity strengths. Let’s find out which of them is the most suitable to use on dogs.

1. Calcium Ascorbate Vitamin C for Dogs

Calcium ascorbate comprises around 80% to 90% vitamin C and 10% calcium. Since this form of vitamin C for dogs is PH-neutral, it has better bioavailability and causes the least side effects.

2. Sodium Ascorbate Vitamin C for Dogs

This type of vitamin carries small amounts of sodium per 1,000 milligrams. Similar to calcium ascorbate, it is pH-neutral. Hence, sodium ascorbate is easily absorbed in dogs’ bodies.

3. Ester C Calcium Ascorbate Vitamin C for Dogs

This is the patented version of calcium ascorbate. Ester C is also PH-neutral. So it is nonacidic and gentle on your dog’s stomach.

Do note that there is a preliminary study comparing the effectiveness of Ester C to pure forms of calcium and sodium ascorbate.

4. Ascorbic Acid Vitamin C for Dogs

Ascorbic acid is closely similar to the naturally produced vitamin C in the canine system. However, it has the least bioavailability out of the 5 vitamin C supplements for dogs.

Due to its poor absorption rate, ascorbic acid is more likely to cause side effects. When using this type of vitamin C, administering it in small doses multiple times a day is advised.

5. Ascorbyl Palmitate Vitamin C for Dogs

Ascorbyl palmitate is quite unique in the sense that it is the only oil-soluble form of vitamin C and it works well with other antioxidants. This type of vitamin C is more effective compared to ascorbic acid.

Is Vitamin C Bad for Dogs in Large Doses?

Yes, vitamin C can be bad for dogs in large doses. Fortunately, its side effects are minimal and mild since it is a water-soluble nutrient.

Ingesting high doses of vitamin C supplements may cause the following adverse reactions:

  • Vomiting
  • Diarrhea
  • Increased urination

Severe vitamin C overdose can lead to the formation of calcium oxalate bladder and kidney stones.

Be sure to administer the right amount of vitamin C supplement to your dog to prevent these health issues from occurring.

How Much Vitamin C for a Dog?

vitamin c supplements and oranges for dogsThe ideal dose of vitamin C for dogs without significant signs of vitamin deficiency but often experiencing stress is 18 milligrams per pound of body weight daily. So if your dog weighs 20 pounds, give him 360 milligrams of vitamin C daily.

Make sure to pair the supplement with food to reduce the chances of side effects. We also suggest spreading out the daily dosage into multiple mealtimes for better absorption.

Dogs with vitamin C deficiency will require higher doses of vitamin C. However, it would be best to consult the vet for the appropriate amount to avoid accidental overdose.

3 Tips for Choosing High-Quality Vitamin C Supplements for Dogs

Here are a few pointers to keep in mind to ensure that you acquire a good vitamin C supplement from a reputable company for your dog:

  1. Check the product if it has a National Animal Supplement Council (NASC) label. This is proof that the vitamin C supplement has passed the requirements and standards of the organization.
  2. Avoid vitamin C supplements containing unnecessary fillers such as colorings, sweeteners, and animal digest. These ingredients can increase the likelihood of upsetting your dog’s stomach.
  3. Look for products that are completely made up of pure vitamin C. High-quality brands will supply a list of ingredient concentrations on its package.

Also, check for a United States Pharmacopoeia (USP) label since it indicates that the product is of the highest quality grade.

FAQs About Vitamin C for Dogs

vitamin c tablets

1. Which Dogs Need Vitamin C?

Dogs with vitamin C deficiency need vitamin C supplementation the most. To know if your dog has this condition, the vet will carry out blood tests.

Canines prone to physical and mental stress can benefit from vitamin C supplementation as well. Exposure to various stressors can slow down vitamin C production in their body.

2. What Vitamin C Can I Give My Dog?

Mineral ascorbates such as calcium and sodium ascorbate are the types of vitamin C you can give to your dog. They have higher bioavailability and are nonacidic, so you do not have to worry much about undesirable side effects.

3. How Can I Add Vitamin C to My Dog’s Diet?

You can add vitamin C to your dog’s diet by incorporating vitamin C-dense food. If you refer to the list we have provided earlier, red bell pepper, orange, and kiwifruit are some dog-friendly options.

4. Can I Give My Dog Vitamin C for Humans?

We advise against giving your dog vitamin C for humans unless the vet instructs you to do so.

The formulation of these products caters to the vitamin C needs of humans and may provide an excessive amount of the nutrients to your dog.

Some vitamin C supplements for humans may also contain ingredients like xylitol, which is toxic to canines.


Healthy dogs can do without vitamin C supplementation because they synthesize this nutrient in their liver.

Vitamin C supplements are more beneficial for dogs with vitamin C deficiency due to illnesses like liver disease. Pooches often subjected to physically or mentally stressful situations may need additional vitamin C too.

Be careful when choosing vitamin C supplements for dogs. Some of its forms work better than others. Opt for mineral ascorbates since they are more bioavailable and cause fewer side effects.

As a dog owner, knowing how different nutrients improve your dog’s body function is crucial in keeping him in the best health. So check out our article talking about the importance of vitamin E in your dog’s diet.

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