Detailed Findings

All of the 40 dog breeds with the shortest life expectancies live on average just under 10-years — more than two years less than the average lifespan for all dogs. On the other hand, the average life expectancy of the breeds on the longest-living dogs list is 14.3 years — two years longer than the average lifespan.

Researchers have found that the larger the dog, the shorter the lifespan, though reasons for this remain unclear. In an article published in the scientific journal “The American Naturalist” in April 2013, “The Size-Life Span Trade-off Decomposed: Why Large Dogs Die Young,” researchers did not find a clear correlation between body size and the onset of senescence, the process of deterioration with age. “We conclude that large dogs die young mainly because they age quickly,” the study said. The research team led by evolutionary biologist Cornelia Kraus of the University of Gottingen in Germany said there is evidence that growing large rapidly and maintaining a large body size might come at the expense of reduced survival.

Historically, larger dogs had been bred to be working dogs and used to hunt bigger animals, pull wagons, or tug fishing nets in cold water. Because of this kind of work, these dogs developed larger and muscular bodies. The need for these bigger dogs to do this work has diminished, but their physical characteristics remain. These larger dogs need physical exertion to keep them healthy.

The study in “The American Naturalist” also said research showed deaths due to neoplastic processes — the uncontrolled growth of cells not under physiologic control — tend to be more common in large dogs than smaller canines.

There are other factors that affect the lifespan of dogs. Inbreeding can reduce their longevity because inbred dogs can pass along genes that contain illnesses specific to that breed. Crossbred dogs have greater longevity. Also, spaying or neutering your canine is believed to benefit the animal’s longer-term health. According to the Humane Society, spaying or neutering dogs reduces their risk of getting certain types of cancers.

Methodology

To identify the dog breeds with the longest (and shortest) life expectancy, 24/7 Wall St. reviewed data from Paul Jones et al’s 2008 study “Single-Nucleotide-Polymorphism-Based Association Mapping of Dog Stereotypes.” This research analyzed the DNA of 148 domestic dog breeds and included various attributes like size, temperament, trainability, and average age at death. The longevity data primarily represents owner surveys. Supplemental data was retrieved from the American Kennel Club (AKC). Additional information was provided by CanineJournal.com. Only dog breeds that are recognized by the AKC were considered.