• Vitamin A: Supports cell growth, healthy eyesight, and immune function. 
• Vitamin B family: Thiamine, riboflavin, pyridoxine, pantothenic acid, and folic acid serve a number of important roles in the body, including metabolism, neurologic function, enzyme function, and reproduction. 
• Vitamin C: Supports immune function and reduces inflammation.
• Vitamin D: Maintains calcium/phosphorus balance for bone development and function.
• Vitamin E: Essential for muscle function, cell function, and reducing damage to cells. 
• Vitamin K: Necessary for proper blood clotting. 
• Choline: Supports liver and brain function. 

Dogs also require a number of minerals, including: 

• Calcium: Important for bone development/maintenance and nerve impulses. 
• Phosphorus: Also plays a role in bone development/maintenance.
• Magnesium: Component of many body tissues and involved in cell communication.
• Iron: Transports oxygen throughout the body. 

These vitamins and minerals are required in precise amounts. Deficiencies can interfere with your pet’s normal bodily functions. In many cases, however, excessively high levels of vitamins or minerals can be just as harmful as low levels of vitamins and minerals.

Vitamins and Minerals in Dog Food 

The Association of American Feed Control Officials (AAFCO) has established nutrient profiles for dogs and cats. In fact, each species has separate guidelines for “Adult Maintenance” and “Growth and Reproduction.” These nutrient profiles outline the precise amount of vitamins and minerals that are required for pets of a given life stage. 

When you purchase dog food, look for an “AAFCO statement of nutritional adequacy or purpose” on the label. Depending on the food, you may find that your dog’s diet is formulated to meet AAFCO standards of nutritional adequacy or that the food has been through feeding trials. As long as your dog’s food contains an AAFCO statement of nutritional adequacy, you can be assured that your dog’s food contains all of the vitamins and minerals needed to support your dog’s health, in the correct quantities. If you give a multivitamin supplement in addition to feeding a diet that already contains all of the vitamins and minerals your dog needs, you run the risk of overdosing your dog on certain vitamins and minerals. 

Are There Any Dogs That Benefit from a Daily Multivitamin?

The only dogs that benefit from a daily multivitamin are dogs that are not already eating a complete and balanced diet. If your dog is currently eating a home-cooked diet or a diet that is not formulated to be nutritionally balanced and complete (these diets may contain a statement that they are recommended for “intermittent or supplemental use only”), your dog may need a vitamin and mineral supplement. Talk to your veterinarian to determine whether your dog needs to take a multivitamin. 

What about Other Vitamin and Mineral Supplements?

In some cases, dogs with a specific medical condition may benefit from the addition of certain vitamin and mineral supplements to their diet. In this case, your veterinarian will be the one to diagnose your dog’s condition and recommend appropriate supplements. 

Specific canine conditions which may be treated with vitamin supplements include the following: 

• Atopy or atopic dermatitis: Polyunsaturated fatty acids, including omega-3 and omega-6 fatty acids, have been shown to potentially lower the need for anti-inflammatory medications in dogs with atopy. 
• Cognitive dysfunction: There is some evidence that dogs experiencing age-related declines in cognitive abilities may show improvement with various supplements, including arginine, antioxidants, B vitamins, and fish oil.
• Osteoarthritis: While studies often have arrived at conflicting conclusions on the benefits of glucosamine and chondroitin supplements on osteoarthritis, many veterinarians and pet owners feel that pets benefit from these supplements and experience a reduction in clinical signs. 

Supplements should be given under the guidance of a veterinarian who is familiar with your pet. Additionally, the benefits of these supplements may vary; in many cases, treating a medical condition requires a combination of supplements and conventional medications. If your pet has a medical condition that may benefit from the use of a supplement, talk to your veterinarian to determine the best supplements for your pet. Your veterinarian can also offer guidance on how to purchase supplements safely. 

Summary

Vitamins and minerals are essential to your dog’s survival. Fortunately, most commercially-available dog foods are formulated to contain all of the vitamins and minerals that your dog needs for a healthy life. Multivitamins are typically only recommended for dogs that are eating a home-cooked diet or otherwise consuming a diet that is lacking in some way. In some cases, veterinarians may also prescribe dietary supplements to aid in the treatment of specific medical issues. Talk to your veterinarian before giving your pet vitamins or supplements.