Slaves of Our Affection. The myth of the Happy Pet. Second Edition.
© Charles Danten 2015
Animals supposedly stimulate good conduct in children, encourage the development of their sense of empathy and compassion, redeem delinquents, contribute to better health, lead to a greater respect for nature and animals, increase the survival rate of cancer patients, help autistic and disabled children improve, facilitate social interactions, relieve stress, anxiety, loneliness, depression, and post-traumatic stress syndrome, etc.
But where is the proof to these claims?
In science, there are two approaches to conducting research:
1. Descriptive or hypothesis-generating studies
These are presented in the form of anecdotal reports. This kind of study is extremely useful in identifying novel phenomena. They help form a hypothesis, which must then be tested by more controlled studies. They rarely demonstrate the value of a treatment or the existence of a causal relationship. Anecdotal reports, testimonials, and expert opinions are the weakest form of evidence. Unless they are documented by hard facts, they do not make a science.
2. Quantitative or hypothesis-testing studies
Newly discovered phenomena are tested with experimental studies or epidemiologic surveys that utilize carefully constructed control groups and allow for the possibility that the hypothesis being tested is false. In other words, it is not enough to “know” something is true; one must prove it by following standard protocols. These are devised to eliminate any biases, which could influence the results and conclusions of a study and thus lead us astray. (1)
The objective of good science is more about disproving a theory than about proving it. If a theory cannot be refuted after a significant number of attempts, it becomes a truth until proven otherwise. Good science always leaves the door open to revision of accepted truths. But one must be extra cautious here because a study of the second type mentioned above can be as flawed as one from the first category. The psychological hang-ups and mental mechanisms of its users being the principal Achilles’ heel of science, before yelling “Eureka!” one must consider the source of financing, the quality of the scientific methodology used as well as the affiliation of the researchers. (2)(3)(4)(5)
Source of financing
Research in the field of zootherapy is financed almost exclusively by the powerful pet industry, and with good reason, pets make up the eighth largest retail industry in the U.S., bigger than toys, hardware, and jewellery, valued at 55 billion dollars in 2013. (6)
According to French ethnologist Jean-Pierre Digard:
Of course, the financial domination of the pet industry would not be a problem if the science it produced weren’t so bad.
Quality of the scientific methodology and affiliation of the researchers
The large majority of studies on the benefits of pets fit into the first category, hypothesis-generating studies. The contributions of pioneers like New York psychiatrist Boris Levinson are merely simple anecdotal observations rather than scientific experiments. Nevertheless, these are the types of studies used by the pet industry to promote the benefits of the human-animal bond. (8)
The theorists and most outspoken proponents of this field of study belong mostly to the field of psychology. This raises a serious credibility problem since in general research in psychology does not follow the scientific method. (9)(10)(11)(12) According to Jacques Forget, vice-dean of research in social sciences at the University of Quebec in Montreal, "a psychology which purports to be scientific should follow the scientific method. However, in many cases, it prefers to rely strictly on authority. [...] In addition, in the field of professional psychology, descriptive research [hypothesis-generating studies] is the preferred type of research […] yet, and in spite of its relevance, it can never replace quantitative research [hypothesis-testing studies] based on evidence and on numerous experimental studies."(13)
In a landmark article published in 1984 in the Journal of the American Veterinary Medical Association, American scientists Alan M. Beck and Aaron Honori Katcher warned of the poor quality of research being conducted in animal-assisted therapy. (14) They debunked the claimed benefits of pets so thoroughly that it is a wonder that the pet industry bothers to continue “research” in this field with such unrelenting intensity and with the exact same flaws reported 30 years ago. (15)(16)(17)(18)(19)(20)
In 1997, after reviewing more than a thousand studies, epidemiologist Dr. T. Allen reported in the above publication: “Most reports describing the effects of human-canine inter-actions fall into categories at the bottom of the hierarchy ladder [of scientific validity]. There are no studies that compare a group of people with pets and one without.” (21)
In 2006, Drs. K. A. Kruger and J. A. Serpell stated:
While some studies have found that positive short-term effects of the placebo type can accrue from interacting with animals, most quality hypothesis-testing studies, many of which are cited below, have found that the health and happiness of pet owners is no better, and in some cases worse, than that of non–pet owners. (23)(24) As stated in 2011 by scientist Harold Herzog, “the existence of a generalized 'pet effect' on human mental and physical health is at present not a fact but an unsubstantiated hypothesis.” (25)
In spite of the evidence, however, the perceived therapeutic benefits of the human-animal relationship for both humans and animals continue to be regarded as a statement of fact, no questions asked, with a surprising and curious lack of skepticism.
Alleged health benefits
In a comparative study, designed to test a hypothesis, professor Mike Kelly of Greenwich University showed that walking without a dog is far healthier than walking with one. Because of a dog’s numerous “pit stops” along the way – which the researchers called “lamppost syndrome” – the owner’s heart is never sufficiently stimulated to benefit. After only fourteen weeks, the weights, cholesterol levels, and blood pressures of the non-owners were significantly lower than of those of the group that owned dogs. Overall, the general health of the group without four-legged companions was much better than that of the group saddled with canine company. (26)
A Finnish study published in 2006, which surveyed 21,000 Finnish adults aged 20 to 54, is one of the few independent studies that has looked at the effects of pets on the general population. In this hypothesis-testing study, scientists Leena K. Koivusilta and Ansa Ojanlatva showed that pet owners are sick more often and do a below-average amount of exercise: 26% of the pet owners in the study were overweight, compared with 21% for those who did not have pets; 16% of the pet owners exercised less than once a month in comparison to 2% for those without pets. The risk of having health problems is 10% to 20% higher in pet owners than in non-pet owners, even when factors such as age and socio-economic level are considered. This is comparable to the risk in bachelors, widowers, and divorcees. Overall, this study associated pet ownership with poor, rather than good, health. (27)
In another very rare hypothesis-testing peer-reviewed comparative study to determine whether pet ownership by elderly people is associated with lower use of health services, Dr. Anthony Jorm from Australia showed that “elderly pet owners did not differ from non-owners on any of the physical or mental health measures or in use of health services.” (28)
Another hypothesis-testing study of 425 heart-attack victims found that pet owners were more likely than non-pet owners to die or suffer remissions within a year of suffering their heart attack. (29)
As for Friedman's anecdotal study on the anxiolytic effects of pets (30), the most frequently cited "study" by pet therapy advocates, it is as deeply flawed (31) as the other studies in this field:
The Japanese, for example, have shown conclusively that the same results can be achieved with pet robots designed for that purpose. (33) Animals have no mysterious qualities that make them irreplaceable.
Alleged psychological benefits
The impact of pets on psychological well-being is also far from being an established fact, as most advocates of this therapy would have us believe. People whose lives are socially unsatisfactory often try to spice things up by acquiring an animal, but according to a Pew Research Center survey of 3,000 Americans, pet owners are not happier than non-owners. (34) A recent study by psychologist Andrew Gilbey has shown that older adults who are highly attached to their dogs tend to be more depressed than individuals who are not as attached to their pets. (35) Researchers in England found that individuals who had acquired pets were just as lonely as they were before they got their pet, and were no happier than participants who had not gotten a pet (36).
In fact, some scientists, such as Finnish researchers Leena K. Koivusilta and Ansa Ojanlatva, believe that a pet is more likely to exacerbate underlying problems, which remain unaddressed. (37) One study of 40,000 Swedes, for example, found that pet owners suffered more than non-pet owners from psychological problems such as anxiety, chronic tiredness, insomnia, and depression (38). According to a Finnish study of 21,000 pet owners, these were at increased risk for hypertension, high cholesterol, gastric ulcers, migraine headaches, depression, and panic attacks. (39) An Australian study of 2,551 elderly adults found that dog ownership was associated with poorer physical health and with depression (40). Finally, in a study of 12,000 American adults, cat or dog ownership was unrelated to mortality rates. (41)
Sharing thoughts and feelings with a person, animal, or object that cannot offer contradiction leads easily to emotional hyper-dependence. Children, as well as immature adults, are particularly vulnerable to the trap. This phenomenon of psychological transference is well-known to psychologists. (21)(43) In other words, the contemplation of self through the distorting prism of an object or an animal that will not or cannot set you straight is both a shelter and a danger. The systematic escape from existential problems short-circuits one of nature’s most potent agents of change: sorrow. Only sorrow can make us appreciate the urgent need of change. Those who avoid it at all costs suffer countless negative effects on their relationships and on life in general.
1. Wilson, C.C. and Barker, S.B. (2003). Challenges in Designing Human-Animal Interaction Research. American Behaviour Scientist, 47 (1), 16-23.
2. Michaels, David (2008). Doubt is Their Product. How Industry’s Assault on Science Threatens your Health. Oxford University Press.
3. Patsy, Bruce (2006). Recent Trials in Hypertension: Compelling Science or Commercial Speech? Journal of the American Medical Association.
4. Ioannidis, J.P.A. (2005). Why most published research findings are false. PLoS Medicine, 2, 696–701.
5. Freedman, D. H. (2010). Lies, damned lies, and medical science. The Atlantic, 306(4), 76-84.
6. Pet Industry Market Size & Ownership (2013). American Pet Products Association.
7. Digard, Jean-Pierre (2005). Les Français et leurs animaux: Ethnologie d’un phénomène de société. Paris: Hachette littératures, Pluriel: ethnologie, 41.
8. For an insider look at the mind boggling world of “research” in zootherapy see: Kaiser, Lana et al. (2004). Can a Week of Therapeutic Riding Make a Difference? A Pilot Study. Anthrozoös, 17 (1), 63-72.
9. Ioannidis, J., Munafò, M. R., Fusar-Poli, P., Nosek, B. A., & David, S. P. (2014). Publication and other reporting biases in cognitive sciences: Detection, prevalence, and prevention. Trends in Cognitive Sciences, 18(5), 235-241.
10. Fanelli, D. (2010). “Positive” results increase down the hierarchy of the sciences. PloS One, 5(4), e10068.
11. Ferguson, C. J. (2009). An effect size primer: A guide for clinicians and researchers. Professional Psychology: Research and Practice, 40(5), 532.
12. Franco, A., Malhotra, N., Simonovits, G. (2014). Publication bias in the social sciences: Unlocking the file drawer. Science, 345(6203), 1502-1505.
13. Jacques Forget (2009). La psychologie est-elle une vraie science? Conference presented to the Quebec skeptics.
14. Beck, A.M. and Katcher, A.H. (1984). A New Look at Pet-Facilitated Therapy. Journal of the American veterinary Association (JAVMA), 184 (4), 15.
15. Chur-Hansen, A., Stern, C., & Winefield, H. (2010). Commentary: Gaps in the evidence about companion animals and human health: Some suggestions for progress. International Journal of Evidenceâï¿½ï¿½Based Healthcare, 8(3), 140-146.
16. Palley, L. S., O'Rourke, P. P., & Niemi, S. M. (2010). Mainstreaming animal-assisted therapy. ILAR Journal, 51(3), 199-207.
17. Wells, D. L. (2009a). The effects of animals on human health and Wellâï¿½ï¿½Being. Journal of Social Issues, 65(3), 523-543.
18. Kazdin, A. E. (2011). Establishing the effectiveness of animal-assisted therapies: Methodological standards, issues and strategies. In P. McCardle, McCune, S., J. A. Griffin & V. 18. Maholmes (Eds.), How animals affect us: Examining the influence of human-animal interactions on child development and human health (pp. 35-51). Washington, DC: American Psychological Association.
19. Marino, L. (2012). Construct validity of Animal-Assisted-therapy and activities: How important is the animal in AAT? Anthrozoös, 25 (Supplement 1), 139-151.
20. Kamioka, H., Okada, S., Tsutani, K., Park, H., Okuizumi, H., Handa, S., Oshio, T., Park, S., Kitayuguchi, J., Abe, T., Honda, T., & Mutoh, Y. (2014). Effectiveness of animal-assisted therapy: A systematic review of randomized controlled trials. Complementary Therapies in Medicine, 22(2), 371-390.
21. Allen, David T. (1997). Effects of Dogs on Human Health. JAVMA; 210 (7).
22. Kruger, K.A. and Serpell, J.A. (2006). Animal-Assisted Interventions in Mental Health: Definitions and Theoretical Foundations. In: Fine, A.H. (Ed.) Handbook on Animal- Assisted Therapy: Theoretical Foundations and Guidelines for Practice, 2nd Edition. New York: Academic Press, 21-38.
23. Herzog, Harold (2011). The Impact of Pets on Human Health and Psychological Well-Being: Fact, Fiction, or Hypothesis? Current Directions in Psychological Science, 20(4), 236–239.
24. Jorm, A.F. et al (1997). Impact of pet ownership on elderly Australians’ use of medical services: An analysis using medicare data. Medical Journal of Australia, 166, 367-377.
25. Herzog, Harold. Art.cited.
26. Dobson, Roger (1998). Walking the Dog Not as Good as Walking Alone. The Independent (London).
27. Koivusilta, Leena K. and Ojanlatva, Ansa (2006). To Have or Not to Have a Pet for Better Health? PLoS One1(1).
28. Parker, G., Gayed, A., Owen, C., Hyett, M., Hilton, T., & Heruc, G. (2010). Survival following an acute coronary syndrome: A pet theory put to the test. Acta Psychiatrica Scandinavica, 121, 65–70.
29. Friedman, E, Katcher, A.H., Thomas, S. A., Lynch, J. J., and Messent, P. R. (1983). Social interaction and blood pressure: Influence of animal companions. The Journal of Nervous and Mental Disease, 171, 461-465.
30. Pachana, Nancy et al. (2005). Relations between Companion Animals and Self-Reported Health in Older Women: Cause, Effect or Artifact? International Journal of Behavioral Medicine, 2 (2), 103-110.
31. Lilienfeld, Scott O. and Arkowitz, Hal (2008). Is Animal Assisted Therapy Really the Cat's Meow? The jury's out on whether animals can initiate long-lasting improvements in mental health. Scientific American.
32. Schwarts, Angela and Patronek, Gary (2002). Methodological Issues in Studying the Anxiety-Reducing Effects of Animals: Reflections from a Pediatric Dental Study. Anthrozoös, 15(4).
33. Shibata, Takanori and Kazuyoshi Wada (2011). Robot Therapy: A New Approach for Mental Healthcare of the Elderly – A Mini-Review. Gerontology, 57. 378–386.
34. Herzog, H. (2010). Some we love, some we hate, some we eat: Why it’s so hard to think straight about animals. New York, NY: Harper.
35. Gilbey, Andrew et al. (2007). A Longitudinal Test of the Belief that Companion Animal Ownership Can Help Reduce Loneliness. Anthrozoös, 20 (4), 345-353.
36. Miltiades, H., & Shearer, J. (2011). Attachment to pet dogs and depression in rural older adults. Anthrozoös, 24, 147–154.
37. Koivusilta, Leena K. and Ojanlatva, Ansa. Art. cited.
38. Müllersdorf, M., Granström, F., Sahlqvist, L., & Tillgren, P. (2010). Aspects of health, physical/leisure activities, work and socio-demographics associated with pet ownership in Sweden. Scandinavian Journal of Public Health, 38, 53–63.
39. Koivusilta, Leena K. and Ojanlatva, Ansa. Art. cited.
40. Parslow, R. A., Jorm, A. F., Christensen, H., & Rodgers, B. (2005). Pet ownership and health in older adults: Findings from a survey of 2,551 community-based Australians aged 60–64. Gerontology, 51, 40–47.
41. Gillum, R.F., & Obisesan, T.O. (2010). Living with companion animals, physical activity and mortality in a US national cohort. International Journal of Environmental Research and Public Health, 7, 2452–2459.
42. Anderson, Digby and Mullen, Roger, editors (1998). Faking it: The Sentimentalisation of Modern Society. Social Affair Unit.
43. Charlton, Bruce (1991). The Moral Case Against Psychotherapy. Psychiatric Bulletin .15, 490-492.