Interacting and petting animals creates a hormonal response in humans that can help fight depression

The next time a dog comes bounding up to you for a wet, sloppy kiss and a good belly rub, don’t back away. In an ongoing study, a University of Missouri-Columbia researcher has found that interacting and petting animals creates a hormonal response in humans that can help fight depression.

“Our preliminary results indicate that levels of serotonin, a hormone in humans that helps fight depression, rise dramatically after interaction with live animals, specifically dogs,” said Rebecca Johnson, MU professor of nursing and veterinary medicine, who presented these initial findings at the Companion Animals: Fountains of Health conference at Barcelona Autonomous University last month. “This hormone is critical in the psychological well-being of an individual. In addition, we have discovered that there is no substitute for the real thing.”

In her study, Johnson, along with Richard Meadows, clinical associate professor of veterinary medicine, is asking dog owners and non-pet owners to play with a live animal or a robot dog for a few minutes at a time. Johnson draws blood from the human and the dog prior to and after the interaction and then compares the blood for hormone levels. People taking part in the study ranged in age from 19 to 73. Preliminary results indicate a significant increase in the levels of serotonin following interaction with the live dog, Johnson said.

“In addition to serotonin, we also are seeing increases in the amounts of prolactin and oxytocin, more of those ‘feel good’ hormones,” Johnson said. “Our research also is trying to determine what types of people would best benefit from being with animals. By showing this benefit, we can help pet-assisted therapy become a medically accepted intervention that might be prescribed to patients.”

“One previous study done in South Africa by Dr. Johannes Odendaal looked at less parameters than the current study and it also found that the interactions were beneficial for both the people and the dogs,” Meadows said. “We expect to see the same benefit to the canines in our study—good for the dogs and the people—a true ‘win-win’ situation.”

The study also indicates that interacting with the robot dog actually decreases levels of serotonin in humans. These preliminary findings could be helpful to psychologists or psychiatrists who want to complement their treatment to a patient suffering from depression, Johnson said. The researchers expect to have final results of the study in the fall.

“We also need to study how the animals react to this attention,” Johnson said. “It’s important to know when we take dogs to nursing homes or hospitals for therapy if they are feeling any kind of stress. We need to find the right balance where both animals and humans can benefit from interacting with each other.”