AVMA News

How dog owner feeding choices correlate with nutritional health outcomes

Demographic data from the Dog Aging Project contribute valuable data for dogs and humans

Updated July 16, 2024

What if people could learn something from dogs about nutrition? Researchers from the Dog Aging Project, the largest cohort study of pet dogs to date, are exploring that possibility by analyzing owner-reported feeding choices.

Dr. Janice S. O’Brien is a research team member with the Dog Aging Project and a doctoral student at the Virginia-Maryland College of Veterinary Medicine. Dr. O’Brien presented the session “Feeding Choices Owners Make: Early Findings from the Dog Aging Project” on June 21 at AVMA Convention 2024 in Austin, Texas.

Because dogs eat a more consistent diet than people, the research group is able to conduct meaningful research in dog nutrition that isn’t feasible in people, she explained. Controlling for dog characteristics is important when comparing nutrition-health outcomes because different populations of dogs eat different foods.

Yellow lab eat food out of metal bowl
“There’s a lot of emotions baked into what an owner chooses to feed their pets,” says Dr. Janice S. O’Brien, a research team member with the Dog Aging Project. Understanding owner food choices can help researchers use demographic data to further dog and human science.

These findings will provide insights for veterinary nutrition researchers as well as general practitioners. Additionally, using dogs as models for translational research could help researchers learn more about human nutrition.

Data collection and analysis

Data from the first two years of the study include 43,517 online surveys completed by dog owners and information about 27,478 dogs.

Owners provided information on dog food choices, including kibble, freeze-dried or home-cooked meals, homemade or commercial raw, semi-dry food, or “other” diets.

These data were analyzed, along with potential confounders such as dog age, sex, body size, and mixed-breed or purebred status, to measure associations (adjusted odds ratios) with dog health outcomes. Outcome categories included dental or oral; skin; orthopedic; gastrointestinal; ear, nose, and throat; kidney or urinary; cardiac; and respiratory.

The diets

The majority (81%) of surveyed dog owners reported that they fed their dog kibble as the primary diet component. A home-cooked diet was the second most popular, at about 4%.

Of the owners who included a secondary diet component, 32% fed canned food, 21% fed home-cooked food, and 17% fed kibble.

Nearly 90% of owners reported feeding their dogs a “very consistent” diet.

Owner and dog demographics

Various owner demographics were correlated with primary diet type. For example, older owners were less likely to feed kibble and instead chose canned or freeze-dried food.

The higher the owner's education level, the more likely they were to feed kibble and less likely to feed home-cooked or commercial raw diets.

In general, the more people who lived in the household, the more likely they were to feed kibble instead of nearly every other food choice.

In dogs, the smaller the size, the less likely they were fed kibble. Homemade raw food was the only diet type that correlated positively with dog size.

Dog activity level also correlated with diet type, with the not active dogs more likely to be fed canned, home-cooked, or semi-dry food over kibble. Very active dogs were most likely to be fed homemade raw food.

There was a correlation between perceived health status and diet type. Owners selected a health status for their dog on a scale of excellent to very poor. Dogs on a kibble diet were significantly healthier than those with a different primary diet type. A worse health status was correlated with dogs that were fed a home-cooked, canned, semi-dry, or “other” diet.

Diet type and health conditions

Understanding owner food choices is imperative to pet nutrition, Dr. O’Brien explained. Food choice correlates with health findings, and health outcomes correlate with diet type, she said.

For example, dogs that ate commercial raw food as a primary diet were 1.7 times as likely to be reported as having a respiratory disease diagnosis than were those that ate kibble.

Dogs fed a home-cooked diet were 1.6 times as likely to have liver disease, 1.3 times as likely to have kidney disease, and 1.4 times as likely to have gastrointestinal disease.

Diet models

The Food Frequency Questionnaire, a self-reported limited checklist of food consumption over time, is a standard tool for quantifying nutritional exposures in people. However, the tool offers benefits for use in dogs as well.

Because most owners know exactly what and when their pets eat, and most feed their pets the same food consistently, this minimal dietary variation is helpful for statistical analysis.

The Dog Aging Project is working to validate a diet questionnaire for use in veterinary research. To date, it has invited 3,035 project participants to keep a three-day food diary, stratified by diet type. Researchers anticipate a 30% response rate, meaning the valuable questionnaire could collect data from around 1,000 dogs.

“As we go into the future, we’ll be able to design more detailed studies looking at all of the different potential additions to diet like treats, supplements, meal toppers, and see if there are any correlations that happen with those,” Dr. O’Brien said.

A version of this story appears in the September 2024 print issue of JAVMA