Research & Education

Pets & Stress Reduction

Dog and cat lovers don’t need any studies to tell them that the love and companionship of pets are good for physical and mental health. Plenty of this research does exist, however, and the shortlist indicates interaction with animals is good for the elderly living with dementia or mental illness, may be beneficial for people undergoing cancer treatment, and may help reduce pain and emotional distress in people living with chronic pain. But what about healthy young people? Is there any benefit to people who seemingly have no “need” for interaction with animals to spend time with them anyway? A study out last month from Washington State University says yes.

The study, “Animal Visitation Program (AVP) Reduces Cortisol Levels of University Students: A Randomized Controlled Trial,” looked at differences in measurements of stress levels among 249 college students (mean age approximately 20 years old, 63% Caucasian, 83% female) after different kinds of interaction with cats and dogs. Subjects were randomly divided into four groups: One group engaged in hands‑on interaction with cats and dogs for 10 minutes. They could pet, play with, and generally “hang out” with the animals as they wished. The second group observed other people petting animals while they waited in line for their turn. The third group watched a slideshow of the animals available, and the fourth group was “waitlisted,” which involved waiting for their turn quietly for 10 minutes without their phones or reading material, and were told they would engage in animal interaction soon.

Salivary cortisol samples from wakeup time, pre-test and post-test showed that the group interacting directly with the animals had the most substantial decrease in cortisol from before and after the intervention. Post-intervention cortisol levels were lowest in the hands-on group and second-lowest in the group that directly observed the hands-on group and were thus exposed to the sights, sounds and social aspects of the hands-on experience even though they didn’t actually physically interact with the animals. This finding is especially interesting because it suggests that even witnessing affection between people and animals can help reduce stress. Subjects in the second group, who directly observed the interactions while waiting their turn, showed less of a decrease in salivary cortisol but it wasn’t nonexistent. Regarding modulation of the HPA-axis, the study authors wrote that even the perception of animals’ capacity to provide social support and stress relief appears to have a beneficial impact.

Not everyone—especially college students—is in a position to adopt a cat or dog. Apartment buildings and homeowner’s associations may have rules that prohibit certain types of pets, and some individuals may have physical limitations that render them unable to care for an animal. The Washington State study suggests a potential alternative strategy by which these people can still experience the well-regarded benefits of interacting with animals is simply to volunteer occasionally at a shelter or other facility where there’s opportunity to have hands-on interactions with animals. For those who are disabled and can’t participate as actively, there may also be a benefit to simply watching others have positive experiences with animals.

Timing could also be a factor. This study was conducted the week before final exams, a time when stress levels are presumably much higher than normal among college students. For people who don’t have pets or don’t regularly interact with animals, it might be helpful to schedule volunteer time or offer to pet-sit for a friend during a time when stress levels are expected to be higher. During such a period it might be difficult to find the time to spend with an animal, but being that just 10 minutes of playtime had a significant impact on salivary cortisol, one need not take an entire day, or even an entire hour, away from their obligations, and the beneficial effect on stress levels might be worth it.

The study involved only one session of human-animal interaction, so we can’t extrapolate the effects beyond this. It’s not possible to predict how long the reduction in cortisol would last and whether there would be a carryover effect lasting several hours or even longer. It may be that one session could promote lower stress for a prolonged period, or that regular exposure to positive animal interactions would have a lasting impact and keep cortisol lower in general.

Overall, the responsibility of regular walks, feeding, vet visits, and the other obligations and expenses that come with being a pet owner may be well worth it for the positive things animals bring to one’s life. And for those who can’t have pets, it’s nice to know that even brief interactions with animals—or even just watching others interact, such as at a dog park—can have a beneficial effect.