By Jennifer Coates, DVM
Antioxidants are finally getting the respect they deserve. When appropriate amounts are included in pet food, antioxidants serve two important functions — keeping food fresh and keeping pets healthy. Let’s take a look at the health benefits.
The Health Benefits of Antioxidants for Pets
Antioxidants play a major role in maintaining your pet's health. They are beneficial in large part because they counter the effects of damaging free radicals in the body.
Free radicals are a natural by-product of metabolism and are produced in greater than normal amounts when pets are sick, elderly, exposed to toxins, or suffer from poor nutrition. Free-radicals contain oxygen and are missing an electron, which makes them highly reactive. They attack and take electrons from cell membranes, proteins, and DNA. The molecule that loses an electron to a free radical often becomes a free radical itself, continuing the cycle.
Antioxidants are different, however. They can donate electrons to free radicals without becoming free radicals themselves, thereby breaking the cycle of molecular and cellular damage. Therefore, an ample dietary source of antioxidants is essential if a pet is to maintain a strong immune system throughout its life and age in a healthy manner.
For example, a series of studies conducted on dogs1 found that older dogs provided with an antioxidant-enriched diet were able to learn complex tasks with more success than those on a control diet. This, researchers hypothesized, was consistent with the assumption that oxidative damage contributes to brain aging in dogs.
Another study2 that used an antioxidant-enriched diet found that older dogs (≥7) were less likely to suffer from age-related behavioral changes associated with cognitive decline, such as excessive licking and patterned pacing. Dogs consuming the antioxidant-enriched diet were also able to recognize their family members and other animals more easily than the control group, as well as display greater attributes of agility.
Antioxidants have even been shown to help dogs and cats that suffer from allergy or coat and skin problems. They also have been shown to promote immune system activity in young animals before vaccination has been implemented.
With all these great benefits, how can you ensure your pet gets antioxidants?
Sources of Antioxidants for Your Dog and Cat
The primary source of antioxidants for dogs and cats should be a complete and balanced diet made from high quality ingredients. Vitamin E, Vitamin C (citric acid), Vitamin A, carotenoids, and selenium are all powerful antioxidants. They are found naturally in many ingredients included in pet foods, but supplements are also used to boost the antioxidant content of the diet without creating nutritional imbalances.
The best resource for advice about a dog or cat’s diet is a veterinarian or veterinary nutritionist who is familiar with that individual’s unique needs. Ask your veterinarian if your pet’s current food provides the antioxidants necessary for a long and healthy life.
1 Milgram NW, Head E, Muggenburg B, et al. Landmark dis- crimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy. Neurosci Biobehav Rev 2002;26:679–695.
Cotman CW, Head E, Muggenburg BA, et al. Brain aging in the canine: a diet enriched in antioxidants reduces cognitive dys- function. Neurobiol Aging 2002;23:809–818.
Ikeda-Douglas CJ, Zicker SC, Estrada J, et al. Prior expe- rience, antioxidants, and mitochondrial cofactors improve cognitive function in aged beagles. Vet Ther 2004;5:5–16.
Milgram NW, Zicker SC, Head E, et al. Dietary enrich- ment counteracts age-associated cognitive dysfunction in canines. Neurobiol Aging 2002;23:737–745.
2 Dodd CE, Zicker SC, Jewell DE, et al. Can a fortified food affect the behavioral manifestations of age-related cognitive decline in dogs? Vet Med 2003;98:396–408.