The Science Of Pets And Sleep: How Animals Help Us Rest Better

As anybody who's cuddled up to a slumbering cat or dog can tell you, pets have a profoundly relaxing, restful effect on our bodies and psyches. So, it's probably no big surprise that there's a growing body of scientific evidence to show what pet owners have always known: Spending time with pets can improve our sleep just as much as it helps us feel more connected to them. And, of course, this effect isn't limited to cats and dogs, although they are by far the most-common family pets — rabbits, guinea pigs, and more may be able to help you slumber a little more peacefully.

From synching heartbeats and promoting restful brain waves to helping us manage our own medical conditions and boosting our feelings of safety, comfort and companionship, here's a closer look at some of the many ways in which animals help us rest better.

Whether it's the simple reassurance of having a loyal friend nearby or the comfort of knowing your dog will bark at any potential intruders — some dog breeds are particularly protective and can help you feel extra safe — many people associate having a pet close by with feelings of greater safety. And while one reasonable side effect of those feelings is sleeping more soundly, that perception of increased safety can manifest in other interesting ways, too.

Consider, for example, a 2024 study published in the journal Anthrozoös. Researchers at the Department of Psychology at Spain's University of Jaén found that test subjects, when presented with images of strangers in urban settings, felt safer and more secure when the same people were depicted with small- to medium-sized dogs as companions, as opposed to simply the people on their own. 

While most safety-related studies focus on dogs, there's no denying the greater sense of comfort that can come from having any pet in the house, from cats to rabbits, birds, lizards and even fish. It's also not a great stretch to see that the sense of security that comes from having a source of unconditional love and companionship in the household can translate to better sleep, too. 

The more connected our world has gotten (thank you, Internet!), the more provocative it has become, relying on our emotional responses to drive clicks, boost engagement, and sell ads. But at the same time, many of us are feeling less connected to our fellow humans, which isn't ideal, as social isolation and loneliness are serious threats to our physical and mental health.

If you're looking into the eyes of a pet — whether it's a hamster, a rabbit, a cat, a bird, or even a fish — you might be looking at part of the solution. Pets have been shown to help soothe isolation and loneliness, reduce stress and anxiety, assist us in regulating our emotional responses, and, above all, provide unconditional love and acceptance — just the sort of reassuring connection that can help you sleep more easily. 

This "pet effect" may be even more profound for people living with mental illnesses. A systematic review published in BMC Psychiatry in 2018 showed that having a pet in the house greatly increased subjects' comfort levels, as well as their self-worth and overall feelings of having a meaning in life. As anyone who's wrestled with a sense of existential dread can tell you, this sort of salve on emotional and psychological stress points can make all the difference between getting a good night's sleep and not.

If you or someone you know is struggling with mental health, please contact the Crisis Text Line by texting HOME to 741741, call the National Alliance on Mental Illness helpline at 1-800-950-NAMI (6264), or visit the National Institute of Mental Health website.

Science is just starting to make inroads toward unraveling the biological "why" and "how" of the mental and emotional benefits of sharing our lives with beloved pets. Some interesting tidbits that've teased out the mystery so far come from a 2011 study published in Anthrozoös, which showed that interacting with your dog for even a short period of time can lower your heart rate, reduce your cortisol levels (that's the stress hormone), and boost your levels of oxytocin (the so-called bonding hormone).

The same study found that owners' insulin levels were also reduced after interacting with their dogs, and a separate study found that when co-sleeping, your heart rate doesn't just lower — it syncs up with your dog's, which can promote the theta brainwaves that are associated with the REM state of deep, restorative sleep. All of these things can contribute to a better night's sleep.

Note: There's been some expert back and forth on whether sleeping with your dog in the bed every night — or even just in the bedroom but not on the bed — is actually a net benefit for your sleep, with some wondering if the extra sound and movement of having the dog nearby ultimately degrade your sleep quality. That said, based on a 2017 study of 40 humans and their dogs that was published in Mayo Clinic Proceedings, having a dog in your bedroom shouldn't inherently disturb your sleep. So, if you and your dog (or any other pet) find comfort in each other's presence, why not give it a shot and see how it goes for you two?

Sleep is a complex beast, which is a big reason why researchers are still pinning down the many ways in which pets help us slumber better. But there's no denying that our sleep stands to improve when any medical conditions we're dealing with are held in check, and a growing body of scientific evidence shows that pets can help with that. "We do best medically and emotionally when we feel securely attached to another," explained Dr. Greg Fricchione, a psychiatrist and the director of the Harvard-affiliated Benson-Henry Institute for Mind Body Medicine, in conversation with Harvard Health Publishing.

For example, a 2013 scientific statement from the American Heart Association highlights the many ways in which pets can help reduce our risk of cardiovascular disease, from lowering blood pressure and cholesterol levels to even increasing your odds of survival after a cardiovascular event. A separate study published in PLoS One in 2016 showed that the routine responsibilities of being a pet owner can help children with diabetes control their blood sugar better.

All of those physical benefits might just help address any issues that have been disturbing your sleep. There's also a promising correlation between having service animals, including emotional support animals, and improved outcomes for people with sleep disorders.

It's no secret that having a dog is a great way to boost your daily physical activity. You both benefit from going for regular walks, playing fetch, and even trying "dog sports" like scent work, canine Frisbee, and dog parkour. This is affirmed by the aforementioned scientific statement from the American Heart Association, which illustrates how having a dog can lead to great increases in physical activity.

Other pets don't seem to come with the same benefits. For instance, most folks who adopt cats don't typically take them on walks or play frisbee with them. Of course, some cat owners have reported greater physical activity after bringing their new pet home, whether from leash-training it or otherwise, and some experts advise that the simple routines of caring for your pet — from feeding it to grooming it and playing with it — can offer a boost in your overall physical activity. And that regular physical activity, in turn, is a vital ingredient in the recipe for good sleep.

Having a consistent sleep schedule and a solid bedtime routine are both crucial parts of sleep hygiene — one of the key pillars of getting a good night's sleep.  And as anyone who's ever had a cat or dog attempt to "herd" them to bed at the appointed hour or a bird shriek indignantly if their cage isn't covered in time for bed will tell you, you've already experienced one of the ways having a pet can lend itself to better sleep.

But tending to your pet's needs can naturally help you establish a sense of structure and purpose in your everyday life, benefitting both yourself and your pets, as everyone involved knows when to look forward to food, rest, and playtime. That, in turn, may lead to greater consistency in your bedtime habits, with the caretaking routine for your pets forming the scaffolding on which you can hang a more complete routine of you own.

Can keeping your pet close help mitigate the effects of sleep disorders like narcolepsy, parasomnia, and sleep apnea? Some experts say yes, and a number of service dogs have been trained to help with these conditions. They can perform tasks like gently nudging their slumbering owner if it looks like they're about to remove the CPAP mask that helps them continue breathing regularly at night or even waking you if your mask has been dislodged and you need to put it back in position. Service animals can also distinguish between sleepwalking and your normal, everyday ambulation and can be trained to physically block you from leaving a room if you're walking in your sleep — an important safety measure for people who might accidentally hurt themselves or others on those late-night walkabouts.

However, not all sleep benefits come from service-trained animals, nor do they all come from dogs. Cats, for example, might help reduce nightmare events in children by the simple virtue of their comforting, trusted presence. This is especially true when children develop a narrative of their cat (or other co-sleeping pet) acting as a protector against nightmares, often with special superpowers that help the child feel more secure. 

Tackling the same question from a slightly different angle, a 2018 study published in the journal Psychoneuroendocrinology showed that military veterans who lived with service dogs had significantly better PTSD-related outcomes than those who didn't. With both insomnia and nightmares being well-known side effects of PTSD, it's really not a stretch to think that soothing one's PTSD symptoms will bring you closer to restful sleep — and many anecdotal reports indicate that untrained pets may offer a similar level of comfort, helping their humans rest more easily at night. 

If you do find security and comfort in having your pet nearby at night, you're far from alone. According to the Sleep Foundation, 56% of adults sleep "with a pet in their bedroom," while about "35% of children share their bed with a pet at night." While sleeping in a "puppy pile" — that is, all curled up together — might come naturally to a child who sleeps deeply, adults and light-sleeping children might want to take a more deliberate approach to planning how they'll share their bed space.

First and foremost, you should have a designated place for your pet to sleep, whether that's on the bed or off. If you let your pet on the bed, make sure your mattress is large enough to accommodate everybody. If you all have a little room to stretch out, you're less likely to bump into each other when you inevitably shift or turn over in the night. 

You'll also want to maintain a bedtime routine that's as predictable as possible. You're essentially training both humans and pets to know what to expect at night, and consistency is key when training — so any humans you co-sleep with should be on board with the plan, too. Making a good walk or a solid play session part of that bedtime routine helps ensure that your pet sleeps more soundly and might even help your sleep, too. Lastly, consider establishing a regular wake-up routine so that your pet doesn't associate the moment you wake up with an opportunity to be fed breakfast. Breaking the direct link between "my human wakes up" and "my human feeds me" gives you more freedom to sleep in or tend to your own needs.

The benefits of co-sleeping aren't a one-way street; some feel the experience just as beneficial for your pet as it is for you. Of course, in cats' cases, they might be doing so for pragmatic reasons: Cats naturally have a slightly higher body temperature than humans — between 101 and 102.5 degrees Fahrenheit — which is why they often bask in the sun and take advantage of other heat sources. The more jaded among us might argue that when they come to sleep with us, they're doing the same thing, treating us like a mobile heating pad that also happens to dispense food when not in bed. 

Still, many pet owners find it obvious that they and their pets derive mutual comfort and assurance from sleeping together. In an op-ed for PetMD, veterinarian Ken Tudor observed that, for him, training is all about bonding — and co-sleeping is key in building that bond and helping humans and pets recognize each others' needs.

I can offer a more personal anecdote to back this up. I recently adopted a cat who turned out to have horrible stomatitis and needed urgent surgery to extract the affected teeth. The surgery was long and involved enough that it took him several days to get back to his normal personality. So, imagine my surprise when, even though I'd only had him for a couple of months, he made it clear that the one place he really wanted to be was in my arms — and that he derived real comfort from sleeping together. I ended up moving my mattress to the floor so he could still sleep with me until he was well enough to jump onto the bed again, and once he'd had that need for close companionship met, it seemed he was able to focus more fully on resting and healing.

As beneficial as sleeping with your pets can be, there are also plenty of valid reasons not to share your bed. If you have allergies or concerns about pests like fleas or ticks, it might make sense to not share bed space, although you could, for instance, pursue medical or veterinary interventions to help reduce allergic reactions.

Behavior issues may crop up, too. For example, consider the challenge of trying to sleep with a rambunctious kitten in the room, a dog who's restless at night, or a cockatoo that talks to itself constantly, even when its cage is covered. Or maybe you have multiple pets, and co-sleeping creates the opportunity for one of more of them to start feeling territorial about the bed. Some of these behavioral issues can be addressed by giving your dog some deliberate sleep training or giving your cat positive reinforcement training. You can also institute healthier habits for everybody, including a pre-bedtime walk or play session. However, depending on what else is happening in your and your pet's life, it's understandable if you'd rather skip the co-sleeping and focus your caretaking energies on other aspects of your lives together. 

Finally, the easiest sleep-related issues to overcome are often logistical ones. Do you have a pet with mobility issues? Pet stairs might help it get on and off the bed, or you could give it a comfortable bed on the floor. Do you want to co-sleep with your pet but need more personal space? It might be worth upgrading to a larger mattress. For cleanliness issues, you could wash your sheets frequently, groom your cat or dog regularly for a cleaner house and to reduce shedding, and even wipe your pet's paws and fur off before it gets into bed.