Vitamin deficiencies in dogs are actually pretty common than most people think.

Sometimes, a dog's underlying health condition is the result of nutrient absorption in the body having been interfered with. Other times, dog vitamin deficiency is the result of a poor, unsubstantial, or unbalanced diet.

So how to make sure that your dog is getting enough nutrients?

While it seems like a good idea to routinely give additional vitamins and minerals to dogs, if the proper dosage isn’t known or used, more damage may be done. 

In this article, let's explore what are the symptoms of vitamin deficiency in dogs. Should we give dogs vitamins every day? And what is the best food for vitamin deficiency?

Vitamin Deficiencies in Dogs: Preparing to Treat it

Always communicate concerns to a veterinarian before diagnosing or attempting to treat your dog yourself. Its perceived vitamin deficiency symptoms could be the result of other underlying issues. 

Never drastically change your dog's diet without the approval or guidance of a veterinarian or canine nutritionist.

An excess of vitamins can create a plethora of other health issues in an animal just as lacking vitamins can.

There are many considerable crucial vitamins that all dogs require in their diet, and the four most common vitamin deficiencies in dogs are:

  • Vitamin A (Beta-carotene) deficiency
  • Vitamin D deficiency
  • Vitamin E deficiency
  • Vitamin B2 (Riboflavin) deficiency

Below we'll take a look at all four of these cases, and talk about the most qualified treatment.

Remember that when addressing this issue through dietary change, a dog’s stomach can adversely react to completely new foods if they aren't properly introduced.

If a change in a dog's typical diet is suggested by a vet, then be sure to change it incrementally for a couple of weeks to a month, depending on the dog’s response to the changes.

6 Reasons Your Dog May be Vitamin Deficient


Homemade Meals May Not Be Properly Balanced

A homemade and/or raw dog food diet may be the best option for some dogs. But if not properly balanced, an excess of vitamins or lack of vitamins can adversely affect the dog. 

Additionally, if the dog wasn’t raised on a homemade or raw diet and is introduced to it suddenly, this can cause stomach issues and even shock and stress for the animal.

Whether cooked meats and vegetables or uncooked ones, the dog's diet should have a sufficient supply of animal protein sources.

It should also contain small amounts of a wide variety of whole grains, vegetables, and healthy fats. Proper numbers should always be followed.

Another potential issue for home-cooked dog food meals is that the nutritional value of many nutrients and mineral-rich foods dissipates when heated (source). 

Dogs normally not fed a raw diet should receive some raw veggies from time to time. Lightly seared meats that are safe when eaten on the rarer side, such as beef, should be added to the diet often.

Poor Quality Canned or Poorly Packaged Dog Food

Dogs fed pre-packaged commercial dog foods that are of lower quality and lacking in nutritional content may experience symptoms linking them to vitamin or mineral deficiencies.

While it’s true that many dog foods advertised are, indeed, “packed” with vitamins, minerals, and other essential nutrients, many of them are synthetic

Absorption of such synthetic nutrients will not be as efficient

While there are not enough studies with dogs on this, plenty of human trials showed that synthetically added vitamins and minerals are not as well absorbed (here and here).

High-quality dog food brands are less likely to have this problem. Alternatively, if feeding a cheaper dog food brand, you can also feed your pet a few fresh, home-created meals once a week to supplement your dog's usual diet of kibble and/or wet food.

No Routine Observation of Daily Food Intake

Dogs who spend most of their time outdoors or whose food bowls aren’t somewhere that’s routinely visited in the household may not be eating enough or they may be eating too much.

Pet owners must always pay attention not only to what type of foods they're feeding dogs but also to how and when a dog consumes said meals. 

Regularly observing your dog and weighing them will also help in noticing any issues early on.

Response to Certain Medications

Some medications can affect the balance of vitamins in the dog's body. 

For example, medications that help with common issues in dogs, such as seizures, glucose levels (diabetes), and several forms of steroids which help with anything from allergies to inflammation may affect Vitamin D levels, studies show.

Most veterinarians are aware of these side effects and will mention if this issue exists when prescribing something. 

This is why it's crucial to consult with a vet before giving your dog any drugs or supplements – their health history needs to be considered.

Parasitic Infection

Even the most commonly occurring parasites can affect a dog's ability to absorb nutrients if they are infected. For example, tapeworms and ringworms live off a dog’s health and whatever the dog consumes, stealing nutrients from them. 

This causes not only vitamin deficiencies in dogs but can also cause malnutrition. This is more common in strays or abandoned canines than domestic pet dogs.

Medical Conditions

Other health maladies such as anemia or diabetes are known for both causing and being the result of nutritional irregularities in dogs. 

Your pet's veterinarian will run appropriate tests to rule out medical conditions like these. He will develop a plan on how to best fix your dog's vitamin deficiency while considering all current health issues.

RELATED: How to Give a Dog Medicine and Vitamins

Effects of Vitamin Deficiencies in Dogs

Lack of sufficient vitamins and minerals leads to different illnesses and disorders in dogs.

Some of the most noticeable, and bothersome, effects of vitamin deficiencies in dogs are:

  • unhealthy skin and coat condition
  • body condition/ malnutrition
  • lack of energy
  • poor oral health
  • allergies and food intolerance
  • eating inappropriate things – shoes, slippers, feces, etc.

How to Treat Vitamin Deficiencies in Dogs

How to Treat to Vitamin Deficiencies in Dogs

After the vet confirms your dog has a vitamin deficiency, you’ll have a greater understanding of how your pooch was affected.  You'll also know how to correct the issue and how to prevent it in the future.

It’s likely your veterinarian will recommend a prescription medication to get the dog’s vitamin levels back to where they should be. 

While this can be a good start, the treatment is continued by the pet owner at home by supplementing a dog’s diet.

Note that vitamin excess is just as much of a threat, with Vitamin D and Vitamin A being the most common suspects.

To avoid vitamin toxicity in dogs, follow this basic rule of thumb:

1 milligram (of vitamin) per pound (of dog)

If your lifestyle or budget proves to make building your dog’s diet too difficult or not possible, there are several “all-in-one” vitamins on the market that are specifically designed with canines in mind.

Some of the most recommended multivitamins for dogs you can try:

Depending on the age and weight of your dog, one to four of these treat-like vitamins will help them stay healthy.

Below are some of the most common vitamin deficiencies in dogs. We have also included available pet supplements to correctly and effectively respond to the disorder.

4 Most Common Vitamin Deficiencies in Dogs

Beta-Carotene Deficiency in Dogs

Beta-Carotene Deficiency


If your dog is lacking Vitamin A, you can supplement its diet with Vitamin A foods like egg yolks, liver, liver oil, or even veggies (kale, carrots, pumpkins, and sweet potatoes). 

While liver oil especially from fish can be quite pricey, your local butcher’s shop is likely to have an affordable selection of beef or poultry livers when you’re in a pinch.

If your dog is acclimated to digesting raw foods, you may choose to serve the liver raw.

However, lightly cooking or even boiling it is also acceptable and recommended if your pet has never been given raw meat.

Please note that the liver is so rich in Vitamin A and other nutrients that it can cause adverse reactions if given too much.  This includes joint tenderness and swelling, and dehydration. 

Animal care professionals recommend giving your dog just a few nibbles at first and waiting to see how it affects their demeanor and stool consistency. 

If their stool remains solid and healthy, then you can feed them liver once a day.

A good rule to follow:

  • 5 ounces to dogs 80 pounds or more
  • 1 ounce to dogs between 40 and 80 pounds
  • 5 ounces to dogs 40 pounds or less

Vitamin D Deficiency in Dogs

Vitamin D Deficiency


Vitamin D is a fat-soluble nutrient, which could equate to toxicity in dogs if given too much Vitamin D. 

In fact, many veterinarians find not so much a deficiency in this vitamin but an excess, with canine patients coming into their office with a loss of appetite, a case of vomiting, and excessive drooling. 

There's even been a recent massive dog food recall by the FDA of many brands, all due to excessive levels of Vitamin D.

However, Vitamin D deficiency can cause fainting, heart failure, and lethargy, among others.

While many food items that help with Vitamin A deficiency will also help with Vitamin D deficiency (egg yolks, fatty meats, and fish), it’s important to not double the quantity of these items unless your dog is especially active and is a larger breed.

Instead, you may want to look into Vitamin D supplements for dogs. You may choose to ask your vet for a better recommendation. 

Exploring these options will help you avoid inadvertently poisoning your furry friend by using improper brands or dosage.

Vitamin E Deficiency in Dogs

Vitamin E Deficiency

  • Cause: Lack of Vitamin E
  • Symptoms: Muscle weakness, may cause reproductive issues, linked to cell damage
  • StudiesHayes, et al. 1969Green, et al. 1977Murray, 1939.


Vitamin E is a great additive for boosting the immune system and promoting healthy skin and coat in dogs. It is also an antioxidant and plays a key role in cell development and strength. 

A great and essential supplement to your dog’s daily meal, Vitamin E is also unlikely to cause adverse effects if your pet happens to be given too much, unlike Vitamin D.

However, this doesn’t mean you shouldn’t carefully craft your dog's meal or give them a bottle of Vitamin E for dogs and let them gobble up every pill. 

Ask your veterinarian for the proper Vitamin E dosage for dogs.

Fatty oils and nuts are great resources for this vitamin. Most professionals recommend sunflower oil, soybean oil, or peanut butter.

Be careful with peanut butter – some are packed with sugars. Look for natural peanut butter (where peanuts are the only ingredient) or visit your local health foods store and ask if they have a nut grinder, which allows you to grind up and make your own peanut butter in the store.

Avoid avocados. Although a healthy fat, many dogs have a sensitivity to it and it may cause a toxic reaction in others.

Instead, fatten up their diet with almond butter or peanut butter, or any other acceptable human foods that are high in Vitamin E.

Riboflavin Deficiency in Dogs

Riboflavin Deficiency

  • Cause: Lack of Vitamin B2
  • Symptoms: Fainting, eye lesions and sores, dry, flaking skin, weakness, weight loss, stunted growth
  • StudiesCline, et al. 1996Sebrell and Onstott.


Riboflavin, or Vitamin B2, is responsible for helping produce red blood cells, which deliver oxygen to different systems of the dog's body. 

Vitamin B2 is also a valuable resource for metabolism, aiding the body in processing foods and transforming them into energy.

If your dog is younger or particularly active, riboflavin is an extremely important additive to their meals. 

To supplement your canine companion’s diet with riboflavin, don’t skimp on healthy meats: beef, poultry, or fish. 

Leafy greens, healthy grains, and live-culture, sugarless yogurts are all great food additives for any canine suffering from riboflavin deficiency. 

Additionally, several fresh herbs are an ideal resource as well: sage, chamomile, peppermint, and raspberry leaves.

Deficiencies in B6 and B12 may also occur in dogs. Some signs and symptoms that your dog has B12 deficiency are reduced appetite, dull hair coat, and diarrhea among others.

As two other members of the water-soluble B vitamins, B6 and B12 are vital in maintaining a dog’s healthy metabolism. 

To prevent or fix that, include delicious meats in your dog’s diet. Add in sugarless peanut butter and mashed or chopped sweet potatoes too.

If your vet noted a Vitamin B deficiency in your dog, meat should take a majority of the portion when building their meal plate.

Vegetables should come in a close second, and any fatty goods (sweet potatoes, peanut butter) should just be a small dollop or sliver.

FAQs on Vitamin Deficiencies in Dogs

What vitamins are crucial for dogs?

Apart from the ones we have discussed above, some of the vitamins that are also crucial for dogs are Vitamins C, B-complex, and K.

Vitamins C and B-complex are water-soluble vitamins that help build bones, teeth, and connective tissues in dogs.

Vitamin K, just like Vitamins A, D, and E is a fat-soluble vitamin. It helps blood to clot and to form protective scabs. However, too much of any of these fat-soluble vitamins can lead to physical abnormalities, especially in their bones.

Vitamin B12 is crucial too in a dog's overall cell system, particularly in its nervous system and the formation of red blood cells. Good thing, there are best foods for dogs to take with B12 deficiency.

It's always best to ask for your veterinarian's recommendation before giving your dog any supplements.

What is the healthiest food to feed your dog?

There are a lot of superfoods you can feed your dog which thankfully, are human foods too! This means they're pretty much accessible and convenient to prepare.

Some of the healthiest food to feed your dogs are kale, carrots, pumpkin, sweet potatoes, fish, dried seaweed (nori), chia seeds, quinoa, yogurt, and blueberries.

On the other hand, the best food for a dog with B12 deficiency is organ meat like heart and liver, and other foods like eggs, goat milk, and fresh raw or lightly cooked muscle meat.

These superfoods contain all the nutrients our dogs need.

Should I give my dog multivitamins?

Multivitamins are generally safe for dogs. However, it should still be given under a veterinarian's supervision.

Remember that some dogs may only be deficient in certain types of vitamins and minerals. Giving them one that fits all may not be enough or worse, give them a surplus of certain vitamins that can do harm instead of good.

Again, you should speak to your veterinarian in case you suspect your dog has a vitamin deficiency.

Vitamin Deficiencies in Dogs: Summary

Vitamin deficiencies in dogs can be quite common, especially since there are many factors that could lead up to them.

This shouldn't be your worry though if you make sure your dog is getting enough nutrients by feeding him well-balanced and nutritious food at home.

Vitamin deficiency in dogs can be easily addressed with proper guidance from the expert and the proper dosage of vitamins and mineral supplements for dogs.

READ NEXT: 13 Balanced Homemade Dog Food Recipes

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Most Common Vitamin Deficiencies in Dogs

Kelly works as a veterinary technician in Austin, TX as well as regular animal rescue volunteer. She's been an animal lover and dog owner since childhood, and has worked in different dog related fields over the last twenty years. Currently she lives with three dogs and a cat.