Companion Animals and Human Health: On the Need for a Comprehensive Research Agenda Toward Clinical Implementation

  • Karine Silva
  • Mariely Lima


The potential association between companion animal guardianship and human health has become a hot topic not only among researchers but also the media and the general public. Has research reached such a point to elevate these animals to the status of “clinical allies”? This chapter aims at providing an objective assessment of the literature allowing the reader to appreciate the distance between current understanding of the effects of companion animals on human health and its application in health promotion and healthcare. It is divided into two main sections. In the first section, evidence suggesting that companion animals may have a positive impact on human health is presented, followed by opposite findings. In the second section, attention is called upon the need for a comprehensive research approach (integrating confounding, mediating, and moderating variables) before we may attribute a “clinical role” to our companion animals.


Companion animals Health promotion Confounders Mediators Moderators 


  1. Allen KM, Blascovich J, Tomaka J, Kelsey RM (1991) Presence of human friends and pet dogs as moderators of autonomic responses to stress in women. J Pers Soc Psychol 61(4):582CrossRefGoogle Scholar
  2. Allen K, Shykoff BE, Izzo JL (2001) Pet ownership, but not ACE inhibitor therapy, blunts home blood pressure responses to mental stress. Hypertension 38(4):815–820CrossRefGoogle Scholar
  3. Allen K, Blascovich J, Mendes WB (2002) Cardiovascular reactivity and the presence of pets, friends, and spouses: the truth about cats and dogs. Psychosom Med 64(5):727–739Google Scholar
  4. Amiot CE, Bastian B (2015) Toward a psychology of human– animal relations. Psychol Bull 141(1):6–47CrossRefGoogle Scholar
  5. Amiot C, Bastian B, Martens P (2016) People and companion animals: it takes two to tango. Bioscience 66(7):552–560CrossRefGoogle Scholar
  6. Anonymous (2018a) All the ways a puppy can make your life better right now. People. Published 2018. Accessed 13 Apr 2018
  7. Anonymous (2018b) Farmácia da Felicidade promove a adoção de animais. Cães de Companhia. Published 2018. Accessed 13 Apr 2018
  8. Archer J (1997) Why do people love their pets? Evol Hum Behav 18(4):237–259CrossRefGoogle Scholar
  9. Bartges J, Kushner RF, Michel KE, Sallis R, Day MJ (2017) One health solutions to obesity in people and their pets. J Comp Pathol 156(4):326–333CrossRefGoogle Scholar
  10. Batty GD, Zaninotto P, Watt RG, Bell S (2017) Associations of pet ownership with biomarkers of ageing: population based cohort study. BMJ 59:j5558CrossRefGoogle Scholar
  11. Bauman AE, Sallis JF, Dzewaltowski DA, Owen N (2002) Toward a better understanding of the influences on physical activity: the role of determinants, correlates, causal variables, mediators, moderators, and confounders. Am J Prev Med 23(2):5–14CrossRefGoogle Scholar
  12. Baun MM, Bergstrom N, Langston NF, Thoma L (1984) Physiological effects of petting dogs: influences of attachment. In: Anderson RK, Hart BL, Hart LA (eds) The pet connection: its influence on our health and quality of life/editors. Minneapolis, Center to Study Human-Animal Relationships and Environments, pp 162–170Google Scholar
  13. Beetz A, Uvnäs-Moberg K, Julius H, Kotrschal K (2012) Psychosocial and psychophysiological effects of human-animal interactions: the possible role of oxytocin. Front Psychol 3:234Google Scholar
  14. Bennett JA (2000) Mediator and moderator variables in nursing research: conceptual and statistical differences. Res Nurs Health 23(5):415–420CrossRefGoogle Scholar
  15. Black K (2012) The relationship between companion animals and loneliness among rural adolescents. J Pediatr Nurs: Nurs Care Child Fam 27(2):103–112CrossRefGoogle Scholar
  16. Budge RC, Spicer J, Jones B, George RS (1998) Health correlates of compatibility and attachment in human-companion animal relationships. Soc Anim 6(3):219–234CrossRefGoogle Scholar
  17. Chowdhury, E. K., Nelson, M. R., Jennings, G. L., Wing, L. M., Reid, C. M., & ANBP2 Management Committee (2017) Pet ownership and survival in the elderly hypertensive population. J Hypertens 35(4):769–775CrossRefGoogle Scholar
  18. Christian HE, Westgarth C, Bauman A, Richards EA, Rhodes RE, Evenson KR et al (2013) Dog ownership and physical activity: a review of the evidence. J Phys Act Health 10(5):750–759CrossRefGoogle Scholar
  19. Chur-Hansen A (2010) Grief and bereavement issues and the loss of a companion animal: people living with a companion animal, owners of livestock, and animal support workers. Clin Psychol 14(1):14–21CrossRefGoogle Scholar
  20. Chur-Hansen A, Winefield HR, Beckwith M (2009) Companion animals for elderly women: the importance of attachment. Qual Res Psychol 6(4):281–293CrossRefGoogle Scholar
  21. Cobb S (1976) Social support as a moderator of life stress. Psychomatic Med 38:300–314CrossRefGoogle Scholar
  22. Cohen S (2004) Social relationships and health. Am Psychol 59(8):676–684CrossRefGoogle Scholar
  23. Cohen S, Gottlieb BH, Underwood LG (2000) Social relationships and health. In: Cohen S, Underwood LG, Gottlieb BH (eds) Measuring and intervening in social support. Oxford University Press, New York, pp 3–25CrossRefGoogle Scholar
  24. Collis GM, McNicholas J (1998) A theoretical basis for health benefits of pet ownership: attachment versus psychological support. In: Wilson CC, Turner DC (eds) Companion animals in human health. Sage Publications, Inc, Thousand Oaks, pp 105–122CrossRefGoogle Scholar
  25. Cutt HE, Giles-Corti B, Wood LJ, Knuiman MW, Burke V (2008a) Barriers and motivators for owners walking their dog: results from qualitative research. Health Promot J Austr 19(2):118–124CrossRefGoogle Scholar
  26. Cutt HE, Knuiman MW, Giles-Corti B (2008b) Does getting a dog increase recreational walking? Int J Behav Nutr Phys Act 5(1):17CrossRefGoogle Scholar
  27. Dwyer F, Bennett PC, Coleman GJ (2006). Development of the Monash dog owner relationship scale (MDORS). Anthrozoös, 19(3):243–256.CrossRefGoogle Scholar
  28. Epping JN (2011) Dog ownership and dog walking to promote physical activity and health in patients. Curr Sports Med Rep 10(4):224–227CrossRefGoogle Scholar
  29. Friedmann E, Gee NR (2017) Companion animals as moderators of stress responses. In: Gee NR, Fine AH, McCardle P (eds) How animals help students learn: research and practice for educators and mental-health professionals. Routledge, Taylor Francis Group, pp 98–110CrossRefGoogle Scholar
  30. Friedmann E, Thomas SA (1995) Pet ownership, social support, and one-year survival after acute myocardial infarction in the Cardiac Arrhythmia Suppression Trial (CAST). Am J Cardiol 76(17):1213–1217CrossRefGoogle Scholar
  31. Friedmann E, Katcher AH, Lynch JJ, Thomas SA (1980) Animal companions and one-year survival of patients after discharge from a coronary care unit. Public Health Rep 95(4):307–312Google Scholar
  32. Fritz CL, Farver TB, Kass PH, Hart LA (1995) Association with companion animals and the expression of noncognitive symptoms in Alzheimer’s patients. J Nerv Ment Dis 183(8):359–363Google Scholar
  33. Garrity TF, Stallones LF, Marx MB, Johnson TP (1989) Pet ownership and attachment as supportive factors in the health of the elderly. Anthrozoös 3(1):35–44CrossRefGoogle Scholar
  34. Gibbs EPJ (2014) The evolution of one health: a decade of progress and challenges for the future. Vet Rec 174(4):85–91CrossRefGoogle Scholar
  35. Gilbey A, McNicholas J, Collis GM (2007) A longitudinal test of the belief that companion animal ownership can help reduce loneliness. Anthrozoös 20(4):345–353CrossRefGoogle Scholar
  36. Handlin L, Hydbring-Sandberg E, Nilsson A, Ejdebäck M, Jansson A, Uvnäs-Moberg K (2011) Short-term interaction between dogs and their owners: effects on oxytocin, cortisol, insulin and heart rate - an exploratory study. Anthrozoös 24(3):301–315CrossRefGoogle Scholar
  37. Handlin L, Nilsson A, Ejdebäck M, Hydbring-Sandberg E, Uvnäs-Moberg K (2012) Associations between the psychological characteristics of the human–dog relationship and oxytocin and cortisol levels. Anthrozoös 25(2):215–228CrossRefGoogle Scholar
  38. Headey B (1999) Health benefits and health cost savings due to pets: preliminary estimates from an Australian national survey. Soc Indic Res 47(2):233–243CrossRefGoogle Scholar
  39. Headey B, Grabka MM (2007) Pets and human health in Germany and Australia: national longitudinal results. Soc Indic Res 80(2):297–311CrossRefGoogle Scholar
  40. Herzog H (2011) The impact of pets on human health and psychological well-being: fact, fiction, or hypothesis? Curr Dir Psychol Sci 20(4):236–239CrossRefGoogle Scholar
  41. Hodgson K, Darling M (2011) Zooeyia: an essential component of “one health”. Can Vet J 52(2):189–191Google Scholar
  42. Hodgson K, Barton L, Darling M, Antao V, Kim FA, Monavvari A (2015) Pets’ impact on your patients’ health: leveraging benefits and mitigating risk. J Am Board Family Med 28(4):526–534CrossRefGoogle Scholar
  43. Hodgson K, Darling M, Freeman D, Monavvari A (2017) Asking about pets enhances patient communication and care: a pilot study. INQUIRY: J Health Care Organ Provision Financ 54:0046958017734030Google Scholar
  44. Holt-Lunstad J, Smith TB, Layton JB (2010) Social relationships and mortality risk: a meta-analytic review. PLoS Med 7(7):e1000316CrossRefGoogle Scholar
  45. House JS, Landis KR, Umberson D (1988) Social relationships and health. Science 241(4865):540–545CrossRefGoogle Scholar
  46. Hyde KR, Kurdek L, Larson PC (1983) Relationships between pet ownership and self-esteem, social sensitivity, and interpersonal trust. Psychol Rep 52(1):110CrossRefGoogle Scholar
  47. Johnson TP, Garrity TF, & Stallones L (1992) Psychometric evaluation of the Lexington attachment to pets scale (LAPS). Anthrozoös 5(3):160–175Google Scholar
  48. Jenkins JL (1986) Physiological effects of petting a companion animal. Psychol Rep 58(1):21–22CrossRefGoogle Scholar
  49. Jennings LB (1997) Potential benefits of pet ownership in health promotion. J Holist Nurs 15(4):358–372CrossRefGoogle Scholar
  50. Kerns KA, Stuart-Parrigon KL, Coifman KG, van Dulmen MH, Koehn A (2018) Pet dogs: does their presence influence preadolescents’ emotional responses to a social stressor? Soc Dev 27(1):34–44CrossRefGoogle Scholar
  51. Kertes DA, Liu J, Hall NJ, Hadad NA, Wynne CD, Bhatt SS (2017) Effect of pet dogs on children’s perceived stress and cortisol stress response. Soc Dev 26(2):382–401CrossRefGoogle Scholar
  52. Lem M, Coe JB, Haley DB, Stone E, O’Grady W (2016) The protective association between pet ownership and depression among street-involved youth: a cross-sectional study. Anthrozoös 29(1):123–136CrossRefGoogle Scholar
  53. Levine GN, Allen K, Braun LT, Christian HE, Friedmann E, Taubert KA et al (2013) Pet ownership and cardiovascular risk: a scientific statement from the American Heart Association. Circulation 127(23):2353–2363CrossRefGoogle Scholar
  54. Luhmann M, Kalitzki A (2018) How animals contribute to subjective well-being: a comprehensive model of protective and risk factors. J Posit Psychol 13(2):200–214CrossRefGoogle Scholar
  55. Mathers M, Canterford L, Olds T, Waters E, Wake M (2010) Pet ownership and adolescent health: cross-sectional population study. J Paediatr Child Health 46(12):729–735CrossRefGoogle Scholar
  56. McConnell AR, Brown CM, Shoda TM, Stayton LE, Martin CE (2011) Friends with benefits: on the positive consequences of pet ownership. J Pers Soc Psychol 101(6):1239–1252CrossRefGoogle Scholar
  57. McDaniel SH, Campbell TL, Hepworth J, Lorenz A (2005) Family-oriented primary care, 2nd edn. Springer, New YorkGoogle Scholar
  58. McNicholas J, Gilbey A, Rennie A, Ahmedzai S, Dono JA, Ormerod E (2005) Pet ownership and human health: a brief review of evidence and issues. BMJ 331(7527):1252–1254CrossRefGoogle Scholar
  59. Miles JN, Parast L, Babey SH, Griffin BA, Saunders JM (2017) A propensity-score-weighted population-based study of the health benefits of dogs and cats for children. Anthrozoös 30(3):429–440CrossRefGoogle Scholar
  60. Miller SC, Kennedy CC, DeVoe DC, Hickey M, Nelson T, Kogan L (2009) An examination of changes in oxytocin levels in men and women before and after interaction with a bonded dog. Anthrozoös 22(1):31–42CrossRefGoogle Scholar
  61. Morley C, Fook J (2005) The importance of pet loss and some implications for services. Mortality 10(2):127–143CrossRefGoogle Scholar
  62. Mubanga M, Byberg L, Nowak C, Egenvall A, Magnusson PK, Ingelsson E, Fall T (2017) Dog ownership and the risk of cardiovascular disease and death–a nationwide cohort study. Sci Rep 7(1):15821CrossRefGoogle Scholar
  63. Muldoon AL, Kuhns LM, Supple J, Jacobson KC, Garofalo R (2017) A web-based study of dog ownership and depression among people living with HIV. J Med Int Res Ment Health 4(4):e53Google Scholar
  64. Nagasawa M, Kikusui T, Onaka T, Ohta M (2009) Dog’s gaze at its owner increases owner’s urinary oxytocin during social interaction. Horm Behav 55(3):434–441CrossRefGoogle Scholar
  65. Nagasawa M, Mitsui S, En S, Ohtani N, Ohta M, Sakuma Y et al (2015) Oxytocin-gaze positive loop and the coevolution of human-dog bonds. Science 348(6232):333–336CrossRefGoogle Scholar
  66. Nelson SK, Kushlev K, Lyubomirsky S (2014) The pains and pleasures of parenting: when, why, and how is parenthood associated with more or less well-being? Psychol Bull 140(3):846–895CrossRefGoogle Scholar
  67. Odendaal JS (2000) Animal-assisted therapy—magic or medicine? J Psychosom Res 49(4):275–280CrossRefGoogle Scholar
  68. Odendaal JS, Meintjes RA (2003) Neurophysiological correlates of affiliative behaviour between humans and dogs. Vet J 165(3):296–301CrossRefGoogle Scholar
  69. Ogechi I, Snook K, Davis BM, Hansen AR, Liu F, Zhang J (2016) Pet ownership and the risk of dying from cardiovascular disease among adults without major chronic medical conditions. High Blood Press Cardiovasc Prev 23(3):245–253CrossRefGoogle Scholar
  70. Parker GB, Gayed A, Owen CA, Hyett MP, Hilton TM, Heruc GA (2010) Survival following an acute coronary syndrome: a pet theory put to the test. Acta Psychiatr Scand 121(1):65–70CrossRefGoogle Scholar
  71. Parslow RA, Jorm AF (2003) The impact of pet ownership on health and health service use: results from a community sample of Australians aged 40 to 44 years. Anthrozoös 16(1):43–56CrossRefGoogle Scholar
  72. Parslow RA, Jorm AF, Christensen H, Rodgers B, Jacomb P (2005) Pet ownership and health in older adults: findings from a survey of 2,551 community-based Australians aged 60–64. Gerontology 51(1):40–47CrossRefGoogle Scholar
  73. Paul ES, Serpell JA (1996) Obtaining a new pet dog: effects on middle school children and their families. Appl Anim Behav Sci 47(1–2):17–29CrossRefGoogle Scholar
  74. Peacock J, Chur-Hansen A, Winefield H (2012) Mental health implications of human attachment to companion animals. J Clin Psychol 68(3):292–303CrossRefGoogle Scholar
  75. 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. Int J Environ Res Public Health 14(3):234CrossRefGoogle Scholar
  76. Rabinowitz PM, Natterson-Horowitz BJ, Kahn LH, Kock R, Pappaioanou M (2017) Incorporating one health into medical education. BMC Med Educ 17(1):45CrossRefGoogle Scholar
  77. Raina P, Waltner-Toews D, Bonnett B, Woodward C, Abernathy T (1999) Influence of companion animals on the physical and psychological health of older people: an analysis of a one-year longitudinal study. J Am Geriatr Soc 47(3):323–329CrossRefGoogle Scholar
  78. Reis M, Ramiro L, Camacho I, Tomé G, Brito C, Gaspar de Matos M (2017) Does having a pet make a difference? Highlights from the HBSC Portuguese study. Eur J Dev Psychol:1–17Google Scholar
  79. Rijken M, van Beek S (2011) About cats and dogs… reconsidering the relationship between pet ownership and health related outcomes in community-dwelling elderly. Soc Indic Res 102(3):373–388CrossRefGoogle Scholar
  80. Rothman KJ, Greenland S (2005) Causation and causal inference in epidemiology. Am J Public Health 95(S1):S144–S150CrossRefGoogle Scholar
  81. Saunders J, Parast L, Babey SH, Miles JV (2017) Exploring the differences between pet and non-pet owners: implications for human-animal interaction research and policy. PLoS One 12(6):e0179494CrossRefGoogle Scholar
  82. Serpell (1991) Beneficial effects of pet ownership on some aspects of human health and behaviour. J R Soc Med 84(12):717–720CrossRefGoogle Scholar
  83. Siegel JM (1990) Stressful life events and use of physician services among the elderly: the moderating role of pet ownership. J Pers Soc Psychol 58(6):1081–1086CrossRefGoogle Scholar
  84. Siegel JM, Angulo FJ, Detels R, Wesch J, Mullen A (1999) AIDS diagnosis and depression in the multicenter AIDS cohort study: the ameliorating impact of pet ownership. AIDS Care 11(2):157–170CrossRefGoogle Scholar
  85. Smith B (2012) The ‘pet effect’: health related aspects of companion animal ownership. Aust Fam Physician 41(6):439–442Google Scholar
  86. Stanley IH, Conwell Y, Bowen C, Van Orden KA (2014) Pet ownership may attenuate loneliness among older adult primary care patients who live alone. Aging Ment Health 18(3):394–399CrossRefGoogle Scholar
  87. Stoeckel LE, Palley LS, Gollub RL, Niemi SM, Evins AE (2014) Patterns of brain activation when mothers view their own child and dog: an fMRI study. PLoS One 9(10):e107205CrossRefGoogle Scholar
  88. Thorpe RJ, Simonsick EM, Brach JS, Ayonayon H, Satterfield S, Harris TB et al (2006) Dog ownership, walking behavior, and maintained mobility in late life. J Am Geriatr Soc 54(9):1419–1424CrossRefGoogle Scholar
  89. Torske MO, Krokstad S, Stamatakis E, Bauman A (2017) Dog ownership and all-cause mortality in a population cohort in Norway: the HUNT study. PLoS One 12(6):e0179832CrossRefGoogle Scholar
  90. Tower RB, Nokota M (2006) Pet companionship and depression: results from a United States internet sample. Anthrozoös 19(1):50–64CrossRefGoogle Scholar
  91. Wells DL (2009) The effects of animals on human health and well-being. J Soc Issues 65(3):523–543CrossRefGoogle Scholar
  92. Winefield HR, Black A, Chur-Hansen A (2008) Health effects of ownership of and attachment to companion animals in an older population. Int J Behav Med 15(4):303–310CrossRefGoogle Scholar
  93. Wood L, Giles-Corti B, Bulsara M (2005) The pet connection: pets as a conduit for social capital? Soc Sci Med 61(6):1159–1173CrossRefGoogle Scholar
  94. Wright HF, Hall S, Hames A, Hardiman J, Mills R, Mills DS, PAWS Team (2015) Acquiring a pet dog significantly reduces stress of primary carers for children with autism spectrum disorder: a prospective case control study. J Autism Dev Disord 45(8):2531–2540CrossRefGoogle Scholar
  95. Xu SL, Trevathan E, Qian Z, Vivian E, Yang BY, Hu LW et al (2017) Prenatal and postnatal exposure to pet ownership, blood pressure, and hypertension in children: the Seven Northeastern Cities study. J Hypertens 35(2):259–265CrossRefGoogle Scholar
  96. Zilcha-Mano S, Mikulincer M, Shaver PR (2012) Pets as safe havens and secure bases: the moderating role of pet attachment orientations. J Res Pers 46(5):571–580CrossRefGoogle Scholar
  97. Zimolag UU, Krupa T (2009) Pet ownership as a meaningful community occupation for people with serious mental illness. Am J Occup Ther 63(2):126–137CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Karine Silva
    • 1
    • 2
  • Mariely Lima
    • 3
    • 4
    • 5
  1. 1.Department of Behavioral Sciences at the Institute of Biomedical Sciences Abel SalazarUniversity of PortoPortoPortugal
  2. 2.Center for Health Technology and Services Research – CINTESIS, University of PortoPortoPortugal
  3. 3.Higher School of Education of Paula FrassinettiPortoPortugal
  4. 4.The School of Health, University of AveiroAveiroPortugal
  5. 5.Center for Health Technology and Services Research – CINTESIS, University of PortoPortoPortugal

Personalised recommendations