Interacting with companion animals (including dogs, cats, rabbits, rodents, horses, fish, birds, reptiles and amphibians) can have a range of physical and mental health benefits for people [1,2]. Animal and human health and welfare are closely linked (concept known as ‘One Health’ and ‘One Welfare’), and animals have been described as promoters, and forecasters of human health .
Physical health benefits
The majority of research on the physical health benefits of companion animals have focused on dogs. Dog ownership has been associated with physical health benefits including:
- Greater physical activity – dog owners spend more time outdoors engaging in exercise (e.g. walking)  and this activity is associated with better physical health parameters (e.g. lower body mass index) .
- Improved cardiovascular health – dog owners have been found to have better cardiovascular health markers (e.g. lower resting heart rate, lower blood pressure, lower cholesterol) and a lower risk of death from cardiovascular problems . However, various studies have found conflicting results and reviewers have cautioned that cardiovascular risk reduction should not be the main reason for pet acquisition .
Mental health benefits
Companion animals can be beneficial for people’s mental health by providing motivation, companionship, stress relief and comfort, and helping to maintain healthy routines . They can also be used for animal-assisted therapy to help people with mental illness, autism, and developmental disorders , performing emotional work (e.g. easing worries), practical work (e.g. symptom distraction), and biographical work (e.g. a sense of identity and self-worth) .
Companion animals can buffer feelings of loneliness and isolation, facilitate social connections , act as social lubricants , and offer social support . For example, many people talk to and confide in their animals .
Benefits for younger people
Overall, companion animals are beneficial to the emotional, cognitive, behavioural, educational, and social development of children and youth. In young people, the presence of a companion animal can fulfil attachment needs, ease anxiety and loneliness, improve self-esteem, facilitate emotional regulation, help build resilience and foster empathy . The presence of a companion animal has been associated with improved learning outcomes (e.g. literacy, verbal skills) as animals may stimulate curiosity, reduce stress, and provide a source of non-judgemental and unconditional support . Growing up with companion animals has also been associated with a lower incidence of allergies in later life .
Benefits for older people
Interacting with companion animals can improve the quality of life of older people, alleviating the symptoms of depression and anxiety, slowing symptoms of dementia, increasing physical fitness, and improving health parameters (e.g. blood pressure) .
Large-scale national surveys have found that people in households which include a companion animal for at least five years, recorded significantly fewer doctor’s visits than people who had never had a companion animal, which may have public health benefits and reduce government expenditure .
Although companion animals can help people in many ways, it is important not to overstate the human health benefits of companion animal ownership because this can create unrealistic expectations . Human health is complex and there are many factors which influence it (both positively and negatively). The effects of companion animals on human health parameters can vary depending on a wide range of human (e.g. owners’ demographics, quality of the human-animal bond), animal (e.g. companion animal type), and study design factors (e.g. which health parameter(s) are being investigated, confounding variables such as socio-economic status) [15,18]. While most studies report that companion animals have beneficial effects on human health, some studies have found no [19–21] or undesirable associations. For example, owners of dogs with Type 2 diabetes were more likely to develop Type 2 diabetes possibly due to shared behaviours and environment .
Developing close emotional attachments to animals and the responsibility of fulfilling their needs, can also involve practical, financial, emotional, and physical health challenges [10,17,23,24]. There are also potential accident, allergy, and disease risks to consider. Nevertheless, a 2022 Australia-wide survey conducted by Animal Medicines Australia found that over 85% of companion animal owners reported that their animals had an overall positive impact on their lives . By providing companion animals with care that meets their physical and mental needs, people can also have a positive impact on their animal’s health and welfare and this is an important component of responsible pet ownership.
 Animal Medicines Australia (2022) Pets in Australia: a national survey of pets and people.
 Macauley L, Chur-Hansen A (2023) Human Health Benefits of Non-Conventional Companion Animals: A Narrative Review. Animals 13:28
 Pastorinho MR, Sousa ACA (2019) Pets as Sentinels, Forecasters and Promoters of Human Health. Springer
 Christian HE, Westgarth C, Bauman A, Richards EA, Rhodes RE, Evenson KR, Mayer JA, Thorpe RJ (2013) Dog ownership and physical activity: a review of the evidence. Journal of Physical Activity and Health 10:750–759
 Curl AL, Bibbo J, Johnson RA (2017) Dog Walking, the Human–Animal Bond and Older Adults’ Physical Health. The Gerontologist 57:930–939
 Kramer CK, Mehmood S, Suen RS (2019) Dog ownership and survival: a systematic review and meta-analysis. Circulation: Cardiovascular Quality and Outcomes 12:e005554
 Wells DL (2019) The state of research on human–animal relations: Implications for human health. Anthrozoös 32:169–181
 Bennetts SK, Crawford SB, Howell T, Ignacio B, Burgemeister F, Burke K, Nicholson JM (2022) Companionship and worries in uncertain times: Australian parents’ experiences of children and pets during COVID-19. Anthrozoös 1–14
 Cherniack EP, Cherniack AR (2015) Assessing the benefits and risks of owning a pet. CMAJ 187:715–716
 Brooks HL, Rushton K, Lovell K, Bee P, Walker L, Grant L, Rogers A (2018) The power of support from companion animals for people living with mental health problems: a systematic review and narrative synthesis of the evidence. BMC psychiatry 18:1–12
 Hughes MJ, Verreynne M-L, Harpur P, Pachana NA (2020) Companion animals and health in older populations: A systematic review. Clinical Gerontologist 43:365–377
 Headey B (2003) Pet ownership: good for health? Medical Journal of Australia 179:460–460
 Chan MC-H, Schonert-Reichl KA, Binfet J-T (2022) Human–Animal Interactions and the Promotion of Social and Emotional Competencies: A Scoping Review. Anthrozoös 1–46
 Purewal R, Christley R, Kordas K, Joinson C, Meints K, Gee N, Westgarth C (2017) Companion animals and child/adolescent development: A systematic review of the evidence. International journal of environmental research and public health 14:234
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 Headey B, Grabka M, Kelley J, Reddy P, Tseng Y-P (2002) Pet ownership is good for your health and saves public expenditure too: Australian and German longitudinal evidence. Australian Social Monitor 5:93–99
 Lima M, Mateus TL, Silva K (2022) With or Without You: Beneficial and Detrimental Associations Between Companion Dogs and Human Psychological Adjustment During a COVID-19 Lockdown Phase. Anthrozoös 1–20
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 Mueller MK, King EK, Halbreich ED, Callina KS (2022) Companion Animals and Adolescent Stress and Adaptive Coping During the COVID-19 Pandemic. Anthrozoös 1–20
 Oliva JL, Johnston KL (2021) Puppy love in the time of Corona: Dog ownership protects against loneliness for those living alone during the COVID-19 lockdown. International Journal of Social Psychiatry 67:232–242
 Batty GD, Zaninotto P, Watt RG, Bell S (2017) Associations of pet ownership with biomarkers of ageing: population based cohort study. bmj 359:
 Delicano RA, Hammar U, Egenvall A, Westgarth C, Mubanga M, Byberg L, Fall T, Kennedy B (2020) The shared risk of diabetes between dog and cat owners and their pets: register based cohort study. BMJ 371:m4337
 Bennetts SK, Crawford SB, Howell TJ, Burgemeister F, Chamberlain C, Burke K, Nicholson JM (2022) Parent and child mental health during COVID-19 in Australia: The role of pet attachment. PLoS One 17:e0271687
 Wells DL, Clements MA, Elliott LJ, Meehan ES, Montgomery CJ, Williams GA (2022) Quality of the Human–Animal Bond and Mental Wellbeing During a COVID-19 Lockdown. Anthrozoös 1–20