Scientific Results: Association Between Diet Type and Owner-Reported Health Conditions in dogs in the Dog Aging Project

Author

Katie Tolbert and Katie Kerr

Where was it published?

The Journal of Veterinary Internal Medicine

 What is this paper about?

We examined how different diet types might be linked to thirteen different categories of health conditions in dogs.  We evaluated data from approximately 27,000 dogs in the Dog Aging Project fed one of four primary diet types.  The diets we studied were commercial dry kibble (91% of dogs), home-cooked food (4%), commercial raw diet (4%), and homemade raw diet (1%).

We did not find that dogs fed raw diets had different rates of skin conditions or gastrointestinal problems.  This is interesting because previous, smaller observational studies suggested that raw diets might be helpful in preventing these health issues, but we did not see evidence of this in our data.  On the other hand, we found some other potentially interesting associations between diet type and certain health issues.  For example, a home-cooked diet was associated with higher rates of several health conditions, and we saw more respiratory conditions among dogs fed a commercial raw diet.  However, we need to emphasize that this study cannot establish cause-and-effect relationships.  An important issue is the possibility of reverse causation – owners might switch their dog to a specialty diet in response to a health condition and that is why we see that the diet and the health condition tend to appear together in our data.  Another study limitation is that the health information we analyzed was provided by owners and we did not have veterinarian confirmation.

What do these results mean for me and my dog?

The study provides a starting point for future research and should not be used to make decisions about what people feed their dogs.  As the Dog Aging Project continues to collect data on the same dogs over time, researchers will be able to better understand how diet affects dogs’ health. When deciding what diet is best for you and your dog, always consult with your veterinarian who can provide personalized recommendations based on your pet’s specific health needs, age, and lifestyle. If you’re considering a homemade diet for your dog, consider involving a board-certified (ACVIM) veterinary nutritionist who can ensure the diet is nutritionally complete and balanced for your pet’s optimal health.

Where can I learn more?

10.1111/jvim.70060

Abstract

Background: Alternative dog diets, such as home-cooked and raw, have grown in popularity. Claims regarding health benefits for these diets have limited supporting evidence. The Dog Aging Project (DAP) is a large-scale research initiative following dogs over their lifetimes that can be used to report how biology, lifestyle, and environment, including diet type, impact health.

Objectives: To evaluate if feeding home-cooked, commercial raw, or homemade raw diets is associated with health conditions compared to extruded diets.

Animal: 27,478 dogs

Methods: We analyzed a large cross-sectional dataset (n =27,478) of dogs fed homemade cooked (n = 1,214), commercial raw (n = 961), homemade raw (n = 329), or extruded (n = 24,974) diets. We investigated associations between diet and 13 owner-reported health condition categories. Logistic regression was used for analysis of all health conditions.

Results: Controlling for sex, age, and body size or breed, a home-cooked diet was associated with higher odds of gastrointestinal (adjusted odds ratio (aOR): 1.4; 95% confidence interval (CI): 1.2-1.7), renal (aOR: 1.3; CI: 1.1-1.6), and hepatic disease (aOR: 1.6; CI: 1.2-2.0) compared to an extruded diet. A commercial raw diet was associated with higher odds of respiratory disease (aOR 1.7; CI: 1.3-2.3) compared to an extruded diet.

Conclusions: Analysis of cross-sectional data can only suggest effects of diet on health and are most useful for hypothesis generation or for testing existing hypotheses.