Scientists discovered which dogs live the longest after studying 155 different breeds, and it could help you be a better pet owner

• Scientists in the UK investigated how a dog's breed, size, sex, and face shape affect lifespan.
• Flat-faced dogs, large dogs, and male dogs typically live shorter lives, the scientists discovered.

Everyone wishes their dog could live forever, but as any pet lover knows, these beloved poochies only spend a fraction of our lives with us.

Whether you're looking to get a new dog or want to make the most of your time with the furry friend you have, it's worth knowing different breeds' typical lifespans.

Now, scientists can answer your questions better than ever before.

A giant new study from the canine welfare organization Dog's Trust UK estimated the lifespans of 155 different dog breeds and discovered that breeds like Tibetan spaniels and Shiba Inus typically live the longest whereas breeds including mastiffs and St. Bernards live some of the shortest lives.

The study, published Thursday in the peer-reviewed journal Scientific Reports, analyzed data from over half a million dogs in the UK to investigate how breed, body size, sex, and face shape impact their life expectancy.

Dogs with the longest and shortest lifespans

The study found the median life expectancy for all dogs to be 12.5 years of age. But some breeds tend to live several years more.

Among purebreds, the five breeds least at risk for early death were Lancashire heelers, Tibetan spaniels, Shiba Inus, papillons, and Lakeland terriers.

Longest living breeds

Others tend to live much shorter lives. Among purebreds, the five breeds most at risk for early death were Caucasian shepherd dogs, Presa Canarios, Cane Corsos, mastiffs, and Saint Bernards.

Shortest living breeds

The fact that these breeds don't live as long is no coincidence. All five are large dogs, which are at a 20% greater risk of early death compared to small dogs, according to the study.

In addition to body size, the study found that sex and face shape also influence longevity.

Male dogs, for example, live on average 0.3 years less than females, which supports the female survival advantage hypothesis that points out in many different mammal species (including humans) females outlive males.

Moreover, dogs with flat faces, like French bulldogs and pugs, have a 40% increased risk of early death compared to dogs with medium-length faces, like Labradors or golden retrievers, lead author Kirsten McMillan told Business Insider.

These flat-faced breeds commonly experience breathing problems and heart disease, according to Blue Cross, which likely explains their shorter life expectancy.

In the graphic below, you can see a list of the dog breeds that live the shortest lives — many are large, like Newfoundlands and Burmese Mountain dogs, and several have flat faces including boxers and bulldogs.

We've mostly talked about purebreds, so far, but the scientists also looked at crossbreeds. They found that the median lifespan for purebreds was 0.70 years longer compared to crossbreeds.

The difference could be explained by the emergence of "designer" crossbreeds like Labradoodles, McMillan said. These breeds emerged from artificial breeding practices but were considered crossbreeds for this study.

As a result, it may explain why the data suggested crossbreeds live shorter lives, McMillan said.

A different kind of study

While previous studies have analyzed factors including sex, face shape, breed, and body size independently, this is the first study to explore how all of them relate to artificial breeding and ultimately how that affects a dog's lifespan, McMillan told BI.

"No one has actually explored the potential link between evolutionary history and lifespan despite the fact that we created these breeds," McMillan said.

Canine domestication began around 16,000 years ago. But the vast diversity of breeds we see today emerged much more recently, some within the last 200 years.

In fact, the Lancashire Heeler — the breed that lives the longest, according to the study — was just recognized as the America Kennel Club's newest dog breed in January. Why breed so many dogs?

Artificial breeding has shortened dogs' lives

Humans began artificially breeding dogs to achieve desired characteristics or abilities.

Dachshunds, for example, were bred specifically to hunt badgers. Their short legs and narrow, long bodies keep them low to the ground to track scents and allow them to squeeze into tight burrows.

Humans have shaped the evolutionary history of dogs for centuries, and in turn, shaped their lifespans.

Artificial breeding practices such as inbreeding, trait selection, and population isolation can reduce genetic diversity and lead to major health concerns, McMillan said.

Nearly 700 inherited disorders have been documented in domestic dogs, including hip dysplasia, endocrine disruption, and blood disorders.

"Ethical and welfare concerns surrounding breeding has become one of the most important issues within canine welfare. And that's not just true for the UK, that's worldwide," McMillan said.

This study can help you be a better pet owner

McMillan hopes that this research will help prospective pet owners make informed choices about which breeds they welcome into their lives, and provide current dog owners with important information about their dog's aging process.

Longevity doesn't just influence the amount of time you spend caring for your pet, but also the risk of navigating big health challenges earlier in your dog's life, which can be costly both financially and emotionally.

"These dogs are members of our family," McMillan said. "We want to ensure that we're providing them with long, happy and healthy lives."