Dogs and humans may share some of the same biological patterns related to lifespan, according to new research from the Canine aging project. The finding could give scientists a useful new way to investigate how aging works in both species.
In a study recently published in The Journals of Gerontology, researchers examined metabolites, small chemicals and molecules created during normal body processes. They found that certain combinations of these metabolites were associated with earlier or later death in dogs in ways that closely resembled patterns previously identified in humans.
“The molecules that are risky for dogs or protective against earlier death are very similar to those in people, showing that we share important features of the biology of aging, which is really interesting and rewarding,” said Dr. Kate Creevy, veterinary director of the Dog Aging Project and professor at the Texas A&M College of Veterinary Medicine and Biomedical Sciences, where the Dog Aging Project’s work is generously supported by the WoodNext Foundation. “Our findings also highlight the value of dogs as a model for studying long-term health and lifespan.”
Search for biological signs of life expectancy
Metabolites can provide a snapshot of what’s happening inside cells, making them useful for detecting biological patterns that may be linked to health and aging.
For the study, researchers analyzed blood samples from dogs participating in the Dog Aging Project. This community-based scientific effort follows dogs throughout their lives, with owners providing detailed information from surveys and, in some cases, physical samples. The research team examined the blood for metabolic patterns associated with lifespan, specifically focusing on whether individual dogs died earlier or later.
“Death is an easy outcome to understand,” Creevy said. “It’s very easy to tell when a person or dog has died, while other characteristics of aging health are a little more nuanced.”
Using mortality as a clear endpoint allows scientists to work backwards and investigate what biological processes may have contributed to the outcome. These processes may include metabolism, inflammation, and the way cells react to stress.
“If we understand why something happened, we have a better chance of identifying ways to change it,” Creevy said.
A metabolic fingerprint of aging
Instead of focusing on individual molecules, the researchers analyzed thousands of metabolites together to look for broader patterns associated with risk. Creevy said these broader clusters can reveal more about what may be happening inside cells than any single molecule alone.
“Some of my colleagues refer to this as a digital footprint,” Creevy said. “We often look at a pattern or cluster that has a relationship with better or worse outcomes rather than just looking at a single molecule.”
These measurable biological indicators, known as biomarkers, can help researchers estimate the likelihood of certain health outcomes by revealing changes occurring within the body.
“It’s important to note that those biomarkers don’t necessarily cause an outcome; when we find a biomarker associated with mortality sooner or later, we don’t know what’s causing it,” Creevy said. “But if we understand why that biomarker is present, we will be able to identify what is causing the relationship.”
Finding these recurring patterns gives scientists potential starting points to investigate the mechanisms behind aging and eventually identify biological targets that could help improve health over time.
Dogs and humans share similar signs of aging
The researchers then asked whether the metabolic patterns seen in dogs also appeared in people. To find out, they compared their results to five large published studies on human mortality that used similar methods to examine metabolites.
In those studies, the signs associated with early or late death were very similar to those found in dogs.
That consistency was one of the most surprising results, adding evidence that dogs and humans share important features of the biology underlying aging.
“We often know a little more about this in people than we do in dogs,” Creevy said. “If we have the same goals, we can take advantage of human research to benefit dogs.”
The similarities could allow scientists to use knowledge already gained in human research to improve canine health, while also using dogs to study how aging develops throughout life.
Why dogs are valuable for aging research
Domestic dogs offer several advantages to researchers studying aging. They share many parts of daily life with humans, including their environment, diets, and activity patterns. That overlap gives scientists the opportunity to examine how lifestyle and environment affect long-term health.
“One of the things we love to learn about dogs when it comes to aging is their wide variety of lifestyles that reflect the lifestyles of their owners in a way that is less true for other companion animals,” Creevy said.
Cats, for example, tend to lead more independent and relatively consistent lifestyles. Dogs are more likely to follow the routines, environments, and activity patterns of the people they live with.
Its shorter lifespan provides another important advantage. Humans, on average, live to be 70 years old, while dogs generally live only 12-13 years. That difference allows researchers to observe aging and lifespan outcomes in dogs much more quickly than would be possible in human studies.
Inside the canine aging project
The research was made possible by the Dog Aging Project, a long-term national study that follows dogs living with owners across the United States.
Participating owners provide extensive information about their dogs’ lives, while a subset also submit biological samples each year. Together, those contributions allow researchers to track changes in health and aging over time.
“Owners who register their dogs do everything they can,” Creevy said. “The dedication and commitment of these owners to participating in research and discoveries to improve the health of dogs is remarkable.”
Creevy said the latest findings are an early but important step toward understanding the mechanisms that influence aging. Researchers have now identified metabolic patterns associated with lifespan, providing them with specific biological signals to investigate further.
“This is a starting point,” he said. “We have identified these metabolites and now we know where to start looking.”
For people who own dogs, Creevy said the practical message is simple. Many of the same behaviors that promote healthier aging in people are likely to benefit dogs as well.
“Keeping them on a healthy diet, at a healthy body weight, and preserving mobility and cognitive health, just like we would do ourselves,” Creevy said. “What’s good for us is probably good for them.”