YOUR DOG ISN'T THE ONLY ONE PAYING ATTENTION TO WHAT'S INSIDE HIS FOOD BOWL. NUTRITIONISTS AND GENETICISTS ARE PEERING IN THERE TOO, SEARCHING FOR WAYS TO IMPROVE CANINE HEALTH, ONE MOLECULAR MORSEL AT A TIME.

There is even a name for this quest—an emerging science known as nutrigenomics. This interplay between genes and nutrients found in certain foods may one day transform the overall health of dogs—and people.

"The science of nutrigenomics gives us great insight into understanding how and why certain canine breeds are predisposed to particular conditions," says John Innes, BVSc, Ph.D., professor of small-animal surgery at the University of Liverpool, England, "This gives us one more tool in our ongoing quest to treat and prevent illness."

The goal is to identify specific nutrients capable of "turning off" bad genes and "turning on" good ones. Scientists hope that this manipulation at the cellular level may help prevent or alleviate osteoarthritis, epilepsy, cancers, and a host of other conditions.

"We hope to be able to put what we call 'personalized nutrition' into the reach of everyone," says senior scientist Jose Ordovas, Tufts University, who is widely regarded as a pioneer in the field of human nutrigenomics. "We can use genetic tools to identify predispositions to disease and tailor the proper recommendations—diet, physical activity, environmental factors, even drug therapies—anything that can be controlled."

Fueling Controversy
The buzz about nutrigenomics has sparked a debate in the veterinary community. That's because much of the research has been conducted by scientists at major commercial dog-food companies and the results have yet to be published in peer-review medical journals.

Some companies, however, are already developing prescription foods aimed at interfering with disease on a molecular level. These include Hill's Pet Nutrition and Nestlé Purina PetCare Company.

At an international conference in London last summer, Hill's Pet Nutrition, for example, introduced a new prescription diet for dogs with arthritis and joint problems.

This diet, called Prescription Diet Canine j/d, includes a specific omega-3 fatty acid called eicosapentaenoic acid (EPA). Clinical studies on the j/d diet, conducted by the company and involving more than 50 practicing veterinarians and 500 dogs, have demonstrated that EPA's high concentrations of fish oil appears to 'turn off' an enzyme that causes cartilage degradation.

While there are many prescription diets on the market catering to specific ills, ages, and weights, the j/d diet is the first designed to work at the molecular level by turning off bad genes. But experts see many more such DNA-targeted foods on the horizon.

"We're only beginning to learn how certain foods can manipulate the genes ... we—and dogs—are born with," says Robert Pickard, Ph.D., director of the British Nutrition Foundation.

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He points out that dogs and humans have a similar number of genes and most canine genes appear to have human equivalents and vice versa.

"We know the 'addresses' of genes," says Pickard. "Now, we need to learn their 'occupations' and what influence certain foods have on modifying these genes."

Experts have identified more than 450 canine genetic diseases. Of these inherited diseases, about 85 percent are due to single genes. Another accomplishment bolstering nutrigenomics: the recent completion of the Canine Genome Project, which maps all the chromosomes in dogs to locate genes causing disease.

Walking Happy
Of the tested dogs in the Hill's study, 82 percent were able to walk without stiffness and display greater range of motion one month after being fed the j/d diet, according to Debra Nichol, Ph.D., vice president of product development for Hill's Pet Nutrition. Of those dogs who required nonsteroidal medications, dosages were able to be decreased by an average of 25 percent.

"The discovery of this omega-3 fatty acid is key to treating and managing canine osteoarthritis," says Nichol. "This diet is a canine solution for dogs with arthritis."

Hector, a 7-year-old Scottish Terrier, was diagnosed with arthritis at age 4. His owner, Judy Smith, tried everything, but nothing seemed to improve his mobility or lessen his joint pain.

After four weeks on the j/d diet, Hector's range of motion and energy levels improved.

"It was an amazing difference in his health after just four weeks on this diet," says Smith, a guide-dog trainer. "He no longer has difficulty going up and down stairs or jumping into my car for a ride."

In Manhattan, Kansas, Lori Michaels began feeding the j/d diet to Derby, her aging agility Shetland Sheepdog, after he displayed noticeable stiffness while training and began pausing before climbing stairs. In one month, Derby showed no signs of stiffness or hesitation when approaching stairs.

"I was skeptical at first, but I've seen the results—Derby is back with a lot of drive," says Michaels. "This whole experience has made me want to learn more about the nutritional aspect to my dog's health."

Jerrold Bell, DVM, a clinical associate professor of genetics in the department of clinical sciences at Tufts, is optimistic that nutrigenomic research will identify genes that cause certain breeds to be prone to kidney stones, hip dysplasia, diabetes, and other health conditions. Once identified, these genes could essentially be silenced or "turned off" with the right recipes.

"Nutrigenomics is a wide-open, far-reaching, and exciting field," says Bell. "As practitioners, we have known all along that arthritic dogs, when given EPA supplements orally, get better, but we never knew why. ... Certain pet food companies are on top of it, researching different disorders and using modern molecular techniques to determine how components of food can impact the health of our pets."

Waiting for Proof
But Tony Buffington, DVM, Ph.D., is reserving judgment, at least until more studies are done.

"I am anxiously awaiting the outcome of independently controlled clinical trials that are published in a peer-reviewed journal," says Buffington, a diplomate of the American College of Veterinary Nutrition and professor in the department of veterinary clinical sciences at The Ohio State University. "It is too early to know the benefits of nutrigenomics.

Arden Moore is the author of Healthy Dog: The Ultimate Fitness Guide for You and Your Dog and an associate member of the International Association of Animal Behavior Consultants. She shares her California home with her dog, Chipper.