Does my dog need vitamins?
Most dogs receive a complete and balanced diet - including necessary vitamins and minerals - from commercially processed dog food, according to the FDA. Dogs fed a homemade diet may need supplements. “It’s absolutely critical, but it should be done to match the diet,” Wynn says. “You can’t just create a meal and give your dog a vitamin.” Check with a veterinarian or nutritionist for help in determining what, if anything, is needed.
Is there any danger in giving my dog vitamins?
Possibly. If an animal already eats a balanced diet and receives excess portions of some vitamins and minerals, they could be harmful, according to the FDA and veterinarians.
Too much calcium can cause skeletal problems, especially in large-breed puppies; too much vitamin A can harm blood vessels and cause dehydration and joint pain. Excess vitamin D can prompt a dog to stop eating, harm bones, and cause muscles to atrophy.
Which vitamins work?
Glucosamine-chondroitin supplements, commonly given to dogs with osteoarthritis, have shown mixed results in testing in humans and animals. A 2007 study published in The Veterinary Journal concluded that dogs treated with glucosamine-chondroitin sulfate showed less pain and more mobility after 70 days of treatment.
Fatty acids can help coats look better. Fish oil supplements also can reduce inflammation, according to a study published in the American Journal of Veterinary Research.
Antioxidants such as vitamins C and E also reduce inflammation and help aging dogs with memory problems, Wynn says. But she’s cautious about recommending supplements, especially for young animals that might be on nutritional supplements for many years. “Almost none of them have been tested for long-term safety in dogs,” Wynn says.