Stress and anxiety are normal responses that both humans and dogs can experience from time to time. They can trigger feelings of being overwhelmed and even have effects on our current mood and physical health. But you can take steps — literally — to reduce stress and keep anxiety at bay.
If you live in one of the more than 60 million households with a dog, emotional support can come with a wagging tail. So let’s talk about the positive effects our furry four-legged companions can have on human stress and anxiety levels. They’re called “companion animals” for good reasons!
Can Dogs Detect Stress and Anxiety?
In short, yes. We give off a variety of chemical signals of our emotional states, and we know dogs can smell the difference,1 even without training. While many dogs are naturally sensitive to human emotional cues, individual responses vary depending on the dog’s breed, training and past experiences. (With training, some dogs can provide early detection for several kinds of cancer and other health issues.) Some dogs can also pick up on clues from our behavior and facial expressions; you’ve probably heard of dogs bringing their owners toys if they see them crying. But the opposite reaction can happen, too. We can spread our emotions to our dogs, in a primitive form of empathy called emotional contagion2 — if you’re stressed, it may cause your dog to feel stressed too!
Dogs Reduce Stress, Anxiety and Depression
According to the Human Animal Bond Research Institute (HABRI), research shows that pet ownership, human-animal interactions and animal-assisted therapy can reduce stress levels and many symptoms of anxiety, which is a common mental health condition. Petting dogs, either your own or a visiting service dog, helps lower heart rates and cortisol levels. People living with depression after a heart attack have better survival rates in addition to improved mental health. And people with post-traumatic stress disorder found a reduction in symptoms and in the severity of the symptoms. A systematic review of studies found that military members and veterans with service dogs experience improved quality of life and life satisfaction generally as well as improvement in specific tasks like social interactions and work attendance.
What Do Dogs Do When They Sense Anxiety in Humans?
One theory that’s supported by science is that interacting with animals — whether pet dogs or therapy dogs for anxiety — boosts our oxytocin levels. Called the “cuddle hormone” or “love hormone,” oxytocin is both a hormone and a neurotransmitter, a chemical messenger that transmits messages around the body.
Studies have found that interacting with our dogs increases the amount of oxytocin in our bloodstream and presumably our brains. Research has also documented significant increases in beta-endorphin, prolactin, phenylacetic acid and dopamine levels, in addition to oxytocin, after 5 to 24 minutes of petting a dog.3 These changes in hormone levels occurred not only in people but also in the dogs being petted.
A quick science lesson here: Oxytocin is probably best known for its roles in reproduction, childbirth, breastfeeding or lactation, and bonding. However, oxytocin is also a natural stress reliever. Oxytocin also produces other changes in the body, such as decreasing heart rate, slowing breathing, lowering blood pressure and inhibiting stress hormones. Beta-endorphin is a neurotransmitter and a hormone that relieves pain and regulates stress responses. One of the body’s naturally occurring opioids, beta-endorphin contributes to “runner’s high.” Prolactin is well known for its roles in pregnancy and lactation but, like oxytocin, also plays a role in lessening stress. Phenylacetic acid is a chemical produced in the body when beta-phenylethylamine is metabolized and can be used as a marker for depression. Dopamine is a neurotransmitter associated with reward and reinforcement of behaviors. Like serotonin, dopamine is a “happy hormone.”
Although much of the research has involved interactions between people and dogs, we now know that cats form secure bonds with their humans, too.
Dogs Help with Anxiety
When we perceive a threat or experience stress, our bodies go into fight-or-flight mode. Cortisol is a key stress-related hormone produced by the adrenal glands and, when released, it causes blood glucose (sugar) to be cranked out for a quick energy boost. Epinephrine, another stress-induced hormone, is also released to get our heart pumping for what’s coming next — regardless of whether we intend to fight or flee. While a little bit of stress can be a good thing, chronic stress takes a tremendous toll on our bodies both physiologically and psychologically.
The good news is that contact with pets has been shown to counteract the stress response with real physiological responses: by decreasing stress hormones and lowering heart rate. Pets also lower our psychological responses to stress. In fact, one study found that just 10 minutes of petting a dog or cat can lower cortisol levels in college students.4
It’s the “Pet Effect”
Our pets can make our brains and our hearts happy. Although research into human-animal interactions and bonds is still relatively new, many studies have shown positive health effects for dog owners. To learn more about the human-animal bond and the “pet effect,” check out the HABRI website.
References
- Wilson C, Campbell K, Petzel Z, Reeve C. Dogs can discriminate between human baseline and psychological stress condition odours. PLoS One. 2022;Sep 28;17(9):e0274143.
- Katayama, M., Kubo, T., Yamakawa, T., Fujiwara, K., Nomoto, K., Ikeda, K., Mogi, K., Nagasawa, M. and Kikusui, T., Emotional contagion from humans to dogs is facilitated by duration of ownership. Frontiers in Psychology. 2019;10:1678.
- Odendaal, J.S. and Meintjes, R.A., Neurophysiological correlates of affiliative behaviour between humans and dogs. The Veterinary Journal. 2003;165(3): 296-301.
- Pendry, P. and Vandagriff, J.L., Animal visitation program (AVP) reduces cortisol levels of university students: A randomized controlled trial. Aera Open. 2019;5(2):2332858419852592.
