Verified by 
A few years ago Riley, a career-change service dog—had previously been a working dog and was now “retired” with new owners—presented to me for excessive activity and agitation. He would run through the house whining and crying, roll around, and repeated these behaviors for up to an hour at a time. He was owned by a wonderful couple who were unable to determine a pattern to the behavior, except that it happened more frequently after he ate. After a few questions they said: “We almost canceled our appointment today because he hasn’t been doing this behavior…after…we…switched…his…food.” They said this literally at that cadence.
It turns out that Riley had a history of diarrhea, and their veterinarian had put him on a commercial veterinary therapeutic diet for his digestive woes. We will never know the real reason for his agitated behavior, but it could have been anything from a food allergy to digestive spasms.
As with dog training, views on nutrition vary widely. And, as with identifying oneself as a ‘dog trainer’, anyone from a qualified board-certified veterinary nutritionist (see dacvn.org) to a pet store employee can claim the title of ‘nutritionist’. It can be dicey to walk the line between belief and proof in this era of anti-science, where someone’s beliefs can carry equal weight with peer-reviewed scientific research, and it is often the loudest person who gets the most press.
Some of these beliefs will be borne out to be true, while others can be misleading or even dangerous. While there are a wide range of opinions and outcomes among the varied views, along with a dose of “I don’t know”, there can be an area of common ground.
There is some convincing evidence that diet can affect a dog’s behavior. Dogs diagnosed with Cognitive Dysfunction Syndrome (CDS), similar to Alzheimer’s Disease in humans, have a slower decline in their cognitive abilities when eating a diet high in certain ingredients, such as antioxidants, mitochondrial co-factors, and/or medium chain triglycerides. The studies that have been done in this area compared a test diet to another (‘placebo’) diet, and thus, while far from perfect, demonstrate a positive effect that these diets can have on dogs.
In a paper published in the highly-regarded journal Nature, researchers identified genetic mutations in the genes of domestic dogs that allow for increased starch digestion relative to wolves. These results indicate that early ancestors of modern dogs thrived on a diet rich in starch, in contrast with the carnivorous diet of wolves. This is in direct opposition to ‘personal observations’ that state that dogs need to eat a high meat/low carbohydrate diet. Other, more limited, studies examine the link between protein content and problem behaviors in dogs. The results of these studies were that higher protein diets are somewhat correlated to increased aggression in dogs.
Your dog’s veterinarian is the best source of information for nutritional information for the individual, since they know the dog and his/her medical history best. And, no, veterinarians do not receive kickbacks from recommending a particular diet, any more than a pet store receives extra income by selling particular foods.
Selection of pet foods can be confusing and overwhelming, especially with added concerns around recalls, and pet food company marketing often relies on the emotions and even the guilt of owners. People do not need to spend a fortune to provide a balanced, wholesome diet formulated on scientific principles by a reputable and experienced company. An informative and reputable website for you and your clients is tufts.edu.
As I continue to strive to discover evidence-based research to help me make decisions in my professional and personal life, we all should strive to be cautiously skeptical when evaluating what is presented to us, from nutrition to general medicine or behavior, and beyond.
**************
Melissa Bain, DVM, DACVB, MS, DACAW, Professor, Clinical Animal Behavior, University of California School of Veterinary Medicine
Dr. Melissa Bain is a Professor of Clinical Animal Behavior, and is board-certified by both the American College of Veterinary Behaviorists and the American College of Animal Welfare. In 2007, she completed a Master’s degree in Advanced Clinical Research from the UC Davis School of Medicine. She is a past president of both the American College of Veterinary Behaviorists and the American Veterinary Society of Animal Behavior. In 2016 she was selected as the Bustad Companion Animal Veterinarian of the Year, awarded by the American Veterinary Medical Association. In 2019 she was awarded the Companion Animal Welfare Award by the World Small Animal Veterinary Association. Additionally, she is the Director of Professional Student Clinical Education for the UC Davis Veterinary Medical Teaching Hospital. Her responsibilities include student and resident education, clinical case management, and research.
