Vitamin D
Natural Remedies

Do Dogs Need a Vitamin D Supplement?

| Modified on Nov 08, 2017

Vitamin D is a fat soluble vitamin. Humans get vitamin D from food sources and the body uses sunlight to produce vitamin D. Dogs also get vitamin D from food sources, but dogs do not produce vitamin D from sunlight. Dogs do need vitamin D however, and if their diet lacks it, or the form of vitamin D is poorly used by the dog’s body, health problems can result.

Vitamin D is critical for proper calcium and phosphorus balance. Vitamin D is needed for healthy bones, muscles and nerves.

Vitamin D deficiency can result from inadequate vitamin D in the diet. Vitamin D deficiency is not uncommon in dogs.

According to veterinarian Dr Walter Gruenberg, “Many homemade diets for dogs are deficient in minerals and have altered calcium:phosphorus ratios. Therefore, a high-quality commercial food, or one designed by a credentialed veterinary nutritionist, is recommended.”5

Health Problems in Dogs from Vitamin D Deficiency

As with humans, inadequate vitamin D can cause rickets. Rickets can cause weakness as well as pain in legs, stiffness and difficulty in getting up. Bones may grow poorly and be soft.

There is also an association between cancer and vitamin D deficiency.

How Much Vitamin D do Dogs Need?

According to AAFCO Dogs:

  • 125 IU Vitamin D per 1,000 calories minimum
  • 750 IU Vitamin D per 1,000 calories maximum

1,000 calories is an average amount for a 33 pound dog. Obviously this number will vary greatly. Older, less active dogs may take in quite a bit less. Active dogs will likely take in more.

Sources of Vitamin D for Dogs

  • 1 teaspoon of cod liver oil  453 IU
  • 1 ounce swordfish              190 IU
  • 1 ounce salmon                  150 IU
  • 1 ounce tuna                        50 IU
  • 1 egg yolk                             40 IU

For a 33 pound dog one of the following would provide at least the minimum amount of vitamin D recommended each day.

  • 1/3 teaspoon cod liver oil
  • 1 ounce of swordfish or codfish
  • 3 ounces of tuna
  • 3-4 eggs with the yolk

Vitamin D Toxicity in Dogs

Because vitamin D is a fat soluble vitamin, it is stored in fat cells. Vitamin D can accumulate in the body over time. Vitamin D toxicity would be more likely when using supplements than with high vitamin D foods. For that reason, if using vitamin D supplements in high doses, it is wise to have vitamin D levels monitored through blood work.

Has your dog experienced vitamin D deficiency? Do you supplement with vitamin D? Please send us some feedback!