It may sound like new age, airy-fairy, wishful thinking, but there is actually solid research to back it up. Being kind feels good and is linked to health and happiness—and researchers are beginning to understand the underlying mechanism that links positive emotion and physical health.
The Vagus Nerve
If you want to understand the link between positive emotion and physical health, it’s important to understand the vagus nerve.
The vagus nerve is a cranial nerve with a huge job. Our bodies actually have two of these long nerves, which extend from the brain stem at the back of the skull all the way through the abdomen, with a number of branching nerves that come into contact with the heart, lungs, voicebox, stomach, ears, and other body parts.
The vagus nerve performs a number of jobs. It transmits incoming and outgoing information to and from the brain. It helps regulate heart rate, controls muscle movement, transmits a variety of chemicals throughout the body, and keeps the digestive tract in working order. But here’s the kicker: the vagus nerve is also tied to social connection. It is linked to nerves that regulate emotional expression, tune our ears to human speech, and coordinate eye contact. It also influences the release of oxytocin, a hormone that is crucial to social bonding.
The Vagus Nerve and Social Connection
Research has shown that higher vagal “tone” is associated with deeper connection and more altruistic behavior. Tone refers to how responsive the vagus nerve is. The vagus nerve regulates heart rate—so a toned or responsive vagus is reflected with higher heart-rate variability. Greater tone means higher heart-rate variability and subsequently, lower risk of cardiovascular disease and other illness.
Kindness, the Vagus Nerve, and Health
So, can positive emotions influence vagal tone and physical health? Researchers conducted a study to examine just that. The study included 65 faculty and staff members at the University of North Carolina. Half of the study participants were randomly assigned to “loving kindness” meditation.
The group took a weekly hour-long class for six weeks where they were taught loving kindness meditation, which involves focusing on warm and compassionate thoughts for both self and others. Participants spent time contemplating their own worries and then those of their friends and family. They were taught to silently repeat phrases like: “May you feel safe, may you feel happy, may you feel healthy, may you live with ease.” Participants were instructed to return to these thoughts every time their mind wandered. What’s more, they were encouraged to practice the loving kindness meditation in stressful situations throughout the week.
Throughout the study period, participants logged their meditation hours as well as their positive and negative emotions. The other half of the study group—the control group—was placed on a waiting list for the meditation class. Both groups were tested before and after the study period on their heart-rate variability as well as their positive emotions.
Participants in the meditation group showed a larger increase in positive emotions than those in the control group. This increase in positive emotion was correlated with a greater sense of social connection—and improved vagal tone.
The researchers are quick to point out that it wasn’t just meditation that led to improved vagal tone—it was the resulting positive emotion and connection. In other words, the improved vagal tone only occurred in meditators who reported becoming happier and more socially connected. Participants who meditated, but didn’t report feeling deeper social connection did not see improvements in vagal tone.
Be Kind to Be Healthy
The bottom line—when practicing kindness leads to positive emotion and deeper social connection, it improves vagal tone and can lead to improved health. In other words, kindness is good for others, good for our relationships—and good for our health. It’s always a good idea to be kind—but if you needed an excuse, do it for your health.
Kok BE, Coffey KA, Cohn MA, et al. How positive emotions build physical health: perceived positive social connections account for the upward spiral between positive emotions and vagal tone. Psychological Sciences. 2013; 24(7): 1123-32.