Introduction and Physiological Responses to Stress

Healthy Pleasure of Their Company: Companion Animals and Human Health Karen Allen, School of Medicine, State University of New York at Buffalo

Stress Relief
Stress Relief


Although most pet owners can tell anecdotes about how their pets are wonderful to be with, especially in stressful and lonely times, is there really evidence that pets can have a positive influence on the health of their owners?

Nearly two decades ago Katcher (1985) suggested that stress reduction and companionship were the two benefits of animal contact most likely to have a positive influence on health. Since that time, a considerable amount of human-companion animal research has increased our understanding of how social relationships with animals may be related to human health and well being. Such studies have been laboratory and community-based and have included intervention as well as survey research. This paper includes examples of interesting research that has contributed to our understanding of the importance of companion animals in our lives.

Physiological Responses to Stress

Because individuals who experience pronounced, frequent, or enduring heart rate and blood pressure responses to stress may be at risk for development of cardiovascular disease (Clarkson, Manuck, & Kaplan, 1986; Manuck & Krantz, 1986), social and environmental factors that may diminish responses to stress are important to consider. Some of the most significant contributions to our understanding of the physiologic effects of human-companion animal bonding have come from the field of nursing. For example, Baun and colleagues have looked at the differential effects of petting one’s own dog and petting a strange dog and have demonstrated that petting a dog with whom a companion bond has been established has a positive cardiovascular effect, with an effect that parallels that of quiet reading (Baun, Bergstrom, Langston, & Thoma, 1984). Based on clinical observations and data from existing studies, researchers have suggested that repeated interaction with a companion animal could have beneficial long-term effects, especially for people experiencing acute or chronic stress (Baun, Oetting, & Bergstrom, 1991). While companion animal physiology studies by nurses have focused mostly on natural settings and resting blood pressure, investigations in psychiatry and psychology have frequently added the dimension of a stressor. For example, Katcher (1981) and Jenkins (1986) reported significant decreases in blood pressure when people talked to and petted their own dogs as opposed to reading aloud.

Some Stress Relief Ideas

The degree to which actually petting an animal is related to health benefits is unclear. Although Voith (1985) suggests that people become attached to their pets as a result of the tactile stimulation of petting, other research has documented that people who report high levels of pet attachment need not touch their pets to exhibit decreased reactivity to stress. For example, two experiments focused on the degree to which a pet dog can substitute for human social support and demonstrated that heart rate and blood pressure responses to acute stress were moderated by just the presence of a pet in the room (Allen & Blascovich, 1991; 1996b). In these studies the presence of best friends and spouses was associated with dramatic increases in autonomic response, while the presence of a much-loved pet was associated with minimal increases. Even people with high levels of hostility and anger (previously demonstrated to be unable to benefit from social support of people) had their best performance on mental arithmetic tasks and lowest cardiovascular responses when their dogs were present.

Perhaps the most interesting finding of this research is that, relative to being alone with a spouse, when people were stressed in the presence of both their pets and spouses, blood pressure and heart rate responses diminished and task performance improved, suggesting the presence of a pet can ameliorate to some degree the presence of a spouse. Participants in these studies repeatedly reported that although they perceived other people as critical and evaluative, pets were thought of as nonjudgmental sources of support. In addition, with pets present, tasks such as mental arithmetic and giving a speech were perceived as a challenge whereas in the presence of spouses and friends they were reported as a threat.

Although for most people the notion of social support provided by pets conjures up an image of a furry domestic animal, an interesting study by Eddy (1996) provides compelling evidence that attachment to any species is likely to elicit favorable physiologic responses in pet owners. Eddy studied relaxation responses and reported that for a snake owner, stroking a pet snake produced the greatest reductions in blood pressure from baseline.