Why do cats live longer than dogs?

Updated 25/09/2024

While the thought of our furry companions no longer being with us is unthinkable, it’s common knowledge that cats have a longer lifespan than dogs.

Pet parents, animal lovers, and experts alike have often contemplated why this is the case. As well as pondering the big question: how can we ensure our beloved animal buddies stay with us for as long as possible?

So, does a cat live longer than a dog? The short answer is, yes, cats generally live longer than dogs. Most cats live well into their teens, while the lifespan of dogs can vary significantly and they often live shorter lives than our feline friends. 

With this in mind, why do cats live longer than dogs? Well, many factors contribute to cats having a longer lifespan than dogs, including size, breeding, environmental factors, lifestyle, biological differences, and susceptibility to health issues. 

Let’s dig deeper into these reasons and discuss what you can do to help your four-legged friend have a long and happy life. 

How size can shape lifespan

The answer to the question “who lives longer, cats or dogs?” seems mostly due to the size of our furbabies. When it comes to the average lifespan of cats and dogs, cats (who usually weigh between 8 to 15 pounds) can live 12 to 20 years. In contrast, dogs vary greatly in size, with smaller breeds like Chihuahuas often living 12 to 20 years, while larger breeds like Great Danes typically have a lifespan of 7 to 10 years. 

To understand why size is a factor, let’s first unpack why small dogs live longer than large dogs. While there are many different theories as to why large dogs live shorter lives than small dogs, most studies point to the fact that large dogs seem to age more rapidly than small dogs and are therefore prone to illnesses associated with old age sooner. 

Another theory is that, for large dogs, their bodies are putting so much effort into their rapid growth, that there’s less of a focus on cell repair and cancer defenses.

Finally, larger, heavier dogs are more likely to suffer from joint, muscle, and heart problems due to fast growth and extra weight. 

So, what about cats? Well, it could be the same reason that small dogs tend to live longer than their taller buddies: they grow less and therefore have fewer complications. However, there are a few other theories that could explain our kitty’s “nine lives”.

Evolution and survival instincts

Cats have some seriously cool physical abilities and survival instincts. Their amazing “righting reflex” allows them to land on their feet during falls, often avoiding serious injuries. Plus, cats have killer-sharp claws and teeth that can be used for self-defense, and their solitary nature helps them stay safe from some infectious diseases. These su-purr-powers enhance their ability to survive in the wild and contribute to their extended lifespans. 

But wait – most of our floofballs don’t need to survive in the wild anymore. In fact many of our feline friends are kept indoors or live in environments where these survival instincts aren’t as needed. While your pampered kitty may not be the solo-hunter that their ancestors were, their (tiny furry) genes may still factor into their continuously longer lives… 

In the animal kingdom, larger animals tend to live longer due to their likelihood of survival. Think how a poor mouse, with predators around every corner, needs to mature rapidly and give birth to many offspring for their species to survive. Since their life expectancy is short, they’ve evolved to live fast lives. 

Our cool cats, however, may have naturally lived longer than their larger canine cousins due to their handful of weapons, paw-some agility, and less social nature – meaning there was less of an evolutionary need for them to mature and reproduce as quickly. This evolutionary trait of longevity may be a factor in why cats live longer than dogs today.

Selective breeding and genetic diversity

Selective breeding has a big impact on the health and longevity of our pet companions. Purebred dogs (and cats) such as Bulldogs and Pugs are prone to respiratory issues due to their brachycephalic (short-nosed) structure. Purebred animals are also more likely to pass down genetic diseases or suffer complications due to inbreeding. 

These genetic conditions can greatly impact our pet pal's quality of life and lifespan. In contrast, mixed-bred animals often enjoy better health due to greater genetic diversity. One study shows that “mixed breed dogs live on average about 1.2 years longer than similarly-sized purebred dogs”. According to the Royal Veterinary College, the results seem similar in cats where “crossbred cats have a longer average lifespan of 14 years compared with 12.5 years for purebred cats.” 

However, it’s more common for dogs to be selectively bred than cats. In fact, only 16%-18% of pet cats are pedigree in the USA, whereas 56% of dog owners in the USA have a purebred pup. This might explain why, on average, cats tend to live longer as there’s a lower amount of selective breeding.

Related article: What are the longest-living dog breeds?

Indoor vs. outdoor living and sociability

Many cats nowadays live only indoors and, in general, indoor cats live longer than their outdoor counterparts. This is because they’re protected from various dangers such as traffic accidents, predators, and diseases transmitted through other animals. The lifespan difference is quite stark between indoor and outdoor cats with indoor cats living 15 to 17 plus years and some outdoor cats sadly living only 2 to 5 years if they are involved in trauma.

While most dogs live primarily indoors (and perhaps have a secure outdoor area to roam in), they’re often regularly taken into the outside world for exercise and socialization. In this case, due to their sociable and curious nature, dogs are more likely to be exposed to diseases, ticks, or eat something poisonous compared to indoor cats. 

This may also contribute to the fact that smaller dogs live longer than larger dogs as smaller dogs are less likely to be let off the leash and free roam, and more often go on shorter walks, are kept close to their pet parents, or are even sometimes taken around in dog carriers. 

In the USA 63% of pet cats are kept entirely indoors and this trend seems to be increasing meaning more and more cats may outlive their dog cousins if they’re kept solely indoors! 

Tips for increasing pet lifespan

So now we’ve covered some of the main reasons why cats live longer than dogs, let’s explore some paw-some tips to increase the lifespans of our furr-ever friends. 

Nutrition and diet

Providing a balanced diet tailored to the specific needs of your pet pal is important for their health and longevity. For cats, this means a diet rich in animal protein, while dogs require a well-rounded omnivorous diet. Consult with your vet to determine the best diet for your snuggle buddy’s age, breed, and health condition.

Related article: What can cats eat? A guide to feline nutrition

Exercise

Regular exercise for both cats and dogs can aid a long, healthy life. A lack of exercise can lead to obesity which significantly impacts an animal's health and causes respiratory issues, joint problems, and some forms of cancer.

Providing a calm environment

Just like us, our animal companions thrive in a peaceful setting where they feel safe and secure. Reducing loud noises, providing a cozy space, and keeping a consistent routine can lower their stress levels and improve their overall well-being. Getting an in-home pet sitter is a great way to keep your beloved pets calm and content when you’re away, as they are in the comfort of their own home with a consistent routine. 

Regular vet check-ups

Expert care and regular veterinary check-ups are a great way to ensure the ongoing health and happiness of your furry family. Routine check-ups allow your vet to early diagnose and treat conditions that could otherwise shorten your precious pet's lifespan. 

Interestingly, the American Animal Hospital Association, found that annual dental cleanings conducted by vets reduced mortality rates by almost 20%. So, could cleaning your pet's pearly whites contribute to their overall health? Maybe, but it could also simply be that pet parents who take their dogs for regular dental cleanings may also take good care of all aspects of their dog’s health with regular vet check-ups.

Vaccinations and neutering

Vaccinations are extremely important in protecting your pet from diseases that affect their longevity. Your furbaby needs yearly vaccines, and your vet can advise the best schedule for them.

There’s evidence that neutering (castrating or spaying) your pet can also increase their longevity and avoid complications further down the line. For example, it can reduce the risk of cancer and decrease aggressive behavior (therefore reducing their chance of getting injured in a fight). Your vet will advise you on the correct time to neuter your pet. 

Treatment of illness

Prompt treatment of illnesses is vital for maintaining your pet’s health. If you’re in any way worried about your pet, we always recommend seeking veterinary advice as soon as possible. Members of TrustedHousesitters have access to our 24/7 Vet Advice Line where a member of our trusted team will answer any of your questions and give the necessary advice to help your furry friend have a long and healthy life.

Meet our veterinary expert, Rebecca

This article has been checked by veterinarian Rebecca MacMillan, BVetMed MRCVS. Rebecca is a companion animal vet who has always had a passion for writing and client communication. Since her graduation from the Royal Veterinary college in 2009 she has gained a wealth of experience in first opinion small animal practice, in both clinical and managerial roles. She currently works in the South West and deals with a variety of routine and emergency appointments, but particularly enjoys medicine cases. Outside of work and writing, she enjoys spending time with her family, including her bouncy flat coated retriever George!