For many people, a pet is far more than a companion—they’re a source of comfort, structure, and joy. Whether it’s a dog greeting you at the door, a cat curling up beside you, or even the gentle rhythm of fish swimming in a tank, there’s something undeniably soothing about being around animals. But beyond the emotional connection, there’s growing scientific evidence that pets can play a real, measurable role in improving mental health. From lowering stress hormones to helping people manage anxiety, depression, and trauma, the bond between humans and animals goes deeper than many might assume, and it’s backed by a surprising amount of research.
The human-animal bond has existed for a very long time.
The relationship between people and animals stretches back thousands of years. Dogs were likely domesticated more than 15,000 years ago, possibly even earlier, based on archaeological findings. Cats have lived alongside humans for at least 9,000 years, with early evidence found in the Near East. Initially, these animals served practical roles: dogs assisted in hunting and security, while cats helped control pests around food stores. But over time, the nature of this relationship changed.
In modern society, animals have moved from the periphery of survival to the centre of emotional wellbeing. Pets are now regarded as family members in many households, and their importance is reflected in everything from how much money we spend on them to how we grieve when they pass. The term “human–animal bond” was first coined in the 1960s, but it’s only in the last two decades that a serious body of scientific research has emerged. Organisations like the Human Animal Bond Research Institute (HABRI) have funded dozens of peer-reviewed studies, showing how deeply intertwined our mental and emotional states can be with the presence of a pet.
What the science says
Pets can have a profound effect on how we think, feel, and function, and science is starting to catch up with what pet owners have long known.
1. Reduced stress and cortisol levels Studies show that interacting with pets—even just stroking a dog or watching fish in an aquarium—can lower cortisol, the hormone associated with stress. One study from the University of Lincoln found that people who had contact with dogs during stressful situations had significantly lower cortisol levels than those who did not, according to data published in Frontiers in Psychology. Even brief sessions, such as university dog-visiting days during exam season, have been shown to reduce students’ self-reported anxiety.
2. Increased serotonin and oxytocin Pets don’t just lower stress hormones—they also help boost feel-good ones. Oxytocin, often called the ‘bonding hormone,’ is released during positive social interactions, including between humans and animals. Eye contact between dogs and their owners, for instance, has been shown to trigger a release of oxytocin on both sides. Serotonin and dopamine, which regulate mood and emotional balance, are also positively affected by spending time with pets. This neurochemical boost helps explain why pets are often recommended as part of treatment plans for mood disorders.
3. Lowered blood pressure and heart rate There’s a growing body of evidence suggesting that pet ownership is good for your heart. The American Heart Association has found that people with pets, especially dogs, often have lower blood pressure, healthier cholesterol levels, and a reduced risk of heart disease. A 2019 study even suggested that dog ownership is associated with increased life expectancy, particularly among those who have experienced heart attacks or strokes. The physical activity required to care for pets, combined with their emotional comfort, offers dual benefits.
4. Reduced loneliness and social isolation For people living alone, particularly older adults, pets can offer vital companionship. The simple act of being responsible for another living being gives structure and meaning to the day. Dogs, in particular, can also increase social interaction: dog owners are more likely to engage in conversations with neighbours, other dog walkers, or people they meet at parks. Studies have shown that pet ownership can reduce feelings of isolation and lead to higher levels of perceived social support. In fact, one survey during the COVID-19 pandemic found that pets were a key source of emotional support during lockdowns.
5. Help with anxiety and depression Many mental health professionals recognise the value of pets in helping people manage chronic anxiety and depression. Pets provide routine, which is particularly helpful for those struggling to get out of bed or stick to a daily schedule. Their presence offers physical comfort and emotional grounding, especially during periods of panic or emotional distress. A study published in BMC Psychiatry found that pets helped participants with severe mental health conditions feel less stigmatised and more motivated to maintain their wellbeing.
Therapy and assistance animals play a huge role.
Animals aren’t just helpful in domestic settings—they’re increasingly used in clinical and therapeutic contexts as well. Animal-assisted therapy (AAT) involves structured interactions between patients and animals, often guided by a professional therapist or healthcare provider. These sessions can take place in hospitals, schools, nursing homes, and rehabilitation centres. AAT has been shown to reduce anxiety in hospital patients, support children with autism, and help veterans with PTSD reintegrate into civilian life.
Psychiatric assistance dogs, meanwhile, are trained to perform specific tasks for people with mental health conditions. These tasks might include waking someone from a nightmare, guiding them to safety during a panic attack, or reminding them to take medication. The charity Dogs for Good in the UK, for example, provides assistance dogs to support people with a wide range of mental and emotional challenges. These animals aren’t just comforting companions. They’re life-changing aides.
It’s not just about dogs and cats.
While dogs and cats are the most common pets, they’re far from the only ones that can support mental health. Birds, rabbits, guinea pigs, reptiles, and fish have all been shown to offer emotional benefits. In therapy settings, smaller animals like guinea pigs or rabbits are often used with children due to their approachable size and calm demeanour. Aquariums have even been installed in dentist offices and care homes to reduce anxiety and promote relaxation. The slow movement of fish has a calming, almost meditative effect.
Some studies have explored the benefits of interacting with farm animals, too. Programmes involving horses (equine therapy) or goats (used in care farms) are increasingly popular in the UK, offering people a chance to reconnect with nature and experience non-judgemental connection.
There are some things to keep in mind, of course.
It’s important to acknowledge that while pets can support mental health, they also come with responsibility. Owning a pet requires time, energy, and often considerable expense, from food and vet bills to insurance and daily care. For some, this added responsibility could create stress rather than relieve it. It’s also essential to choose a pet that suits your lifestyle and living arrangements. A high-energy dog in a small flat with no garden may cause more anxiety than peace.
It’s also worth noting that not everyone finds animal companionship beneficial. Allergies, past trauma, or simply a different set of needs can mean that having a pet isn’t the right choice. And while pets can offer emotional support, they’re not a replacement for professional help. Therapy, medication, peer support, and self-care remain vital parts of a mental health toolkit.
The connection between people and animals is ancient, instinctive, and incredibly powerful.
As research continues to uncover the psychological, physiological, and social benefits of pet ownership, it’s clear that animals offer far more than entertainment or company. They provide stability, comfort, and connection in a world that often feels overwhelming.
From reducing stress hormones and improving heart health to easing symptoms of anxiety and depression, pets are silent but effective allies in the fight for mental wellbeing. Whether it’s a loyal dog, a curious cat, a soft rabbit, or a slow-moving turtle, the presence of an animal in our lives can remind us of something simple but profound. That love, loyalty, and comfort often come from the most unexpected places.