Dogs are not only companions but powerful models for studying age-related disease. They develop many of the same conditions humans do— including dementia— and their brains are similar to ours in structure and function. The Dog Aging Project is using that similarity to search for ways to lengthen healthy lives for both species.
Launched in 2014 by biologist Matt Kaeberlein and collaborators, the Dog Aging Project is a broad partnership of pet owners, veterinarians and researchers. The effort has enrolled more than 50,000 pet dogs from hundreds of clinics and hospitals across the United States. Participants provide detailed information about diet, exercise and health; researchers collect blood biomarkers and brain imaging; and the resulting dataset is made available to scientists worldwide.
Kaeberlein and colleagues point out that many fundamental aging processes are conserved across animals. Because of this, treatments that slow aging in lab species might also work in dogs. Dogs occupy a useful middle ground between mice and people: they share our homes and exposures, often eat similar food and exercise alongside us, yet age much faster. That compressed timescale can deliver decades’ worth of aging data in five to ten years.
Veterinary neurologist Stephanie McGrath oversees measures of cognitive change in the project’s dogs. Dogs undergo structured tests— for example, memory tasks in which a treat is hidden and the animal must recall its location. Owners such as Pat Schultz enroll pets like Murphy, a 12-year-old shepherd–poodle mix, partly because of personal experience with human dementia. Schultz’s husband had Alzheimer’s, and Murphy was a steady companion. Over time Murphy became more anxious and struggled with memory tasks, patterns consistent with age-related cognitive decline.
Analyses from the project are already linking lifestyle and environment to disease risk. One study found dogs living with other dogs tend to have fewer illnesses. Another revealed that lack of exercise was associated with a roughly sixfold higher risk of cognitive impairment. These observational findings help prioritize interventions to test in clinical trials.
When enrolled dogs die, many owners consent to donate their pets’ brains for neuropathological study. Dr. Dirk Keene at the University of Washington, who has studied human Alzheimer’s pathology for years, examines these canine brains and emphasizes the parallels: dogs have frontal, temporal and occipital lobes, and dementia in dogs can produce similar patterns of brain shrinkage and enlarged fluid spaces. Under the microscope some donated brains show hallmark Alzheimer’s features such as beta-amyloid plaques that resemble those seen in humans.
One intervention under study is rapamycin, a drug that has extended healthy lifespan and slowed cognitive decline in rodents. In an initial pilot, 12 dogs showing signs of dementia received either rapamycin or placebo. Postmortem analysis by molecular biologist Julie Moreno found fewer microglia—immune cells linked to neuroinflammation—in treated animals, suggesting reduced inflammatory activity. Those encouraging early signals led to a larger, NIH-funded trial enrolling hundreds of dogs to more rigorously test whether rapamycin can safely improve healthspan.
Beyond academic research, private companies are developing preventive therapies for aging pets. Loyal, a biotech started by Celine Halioua in 2019, aims to produce drugs administered preventively—similar to a daily statin—to keep dogs healthier for longer. The company hopes to add roughly one extra healthy year of life, though benefits may vary by individual. One candidate is in trials for dogs older than ten; the FDA has reviewed safety data and issued a “Reasonable Expectation of Effectiveness,” while final efficacy results will take time. The prospect of faster answers and translatable biology has attracted substantial venture capital to canine longevity startups.
For owners like Schultz, participation is motivated by compassion and practicality. After losing her husband to Alzheimer’s complications, she focuses on maximizing Murphy’s comfort. She notes that practical care measures—consistent routines, reassurance and attention—help both people and dogs with cognitive decline.
By combining large-scale observational data, tissue donation and controlled clinical trials, the Dog Aging Project aims to speed up discoveries about preventing or slowing age-related diseases. Studying naturally occurring aging in a species that shares our environment and shows comparable pathology could improve life quality for dogs and yield insights that someday translate into better treatments for human aging and dementia.