Among men, the hormone oxytocin was found to strengthen spiritual beliefs.
Lead author Patty Van Cappellen, associate director of the Interdisciplinary and Behavioral Research Center at Duke University in Durham, NC, and colleagues found that men given oxytocin nasal spray reported a greater sense of spirituality than those who did not receive the hormone.
Additionally, men who received oxytocin reported experiencing more positive emotions during meditation.
Van Cappellen and team recently published their findings in the journal Social Cognitive and Affective Neuroscience.
Oxytocin is a hormone and chemical messenger produced by the brain's hypothalamus, and it plays a key role in childbirth and breast-feeding.
Oxytocin is also known for its role in maternal bonding, and there is strong evidence that the hormone is important for social bonding, empathy, trust, and sexual pleasure, hence why it is often dubbed the "love hormone."
Now, the findings from Van Cappellen and colleagues suggest enhanced spirituality could be another effect of oxytocin on human psychology.
For their study, the team enrolled 83 middle-aged men and randomly assigned them to receive either intranasal oxytocin or a placebo.
Immediately after and 1 week later, subjects completed a questionnaire asking about their spiritual beliefs. They also took part in a guided meditation exercise, and they were asked what emotions they felt during the exercise.
Oxytocin-spirituality link strongest for men with certain CD38 gene variant
Compared with men who received the placebo, those who received oxytocin were more likely to say spirituality was important to their lives and that life had meaning and purpose, the team reports, regardless of whether or not they were part of an organized religion.
Furthermore, men who received oxytocin were more likely to say they were interconnected with other individuals and living things, compared with those who received the placebo.
Additionally, the researchers found men who received oxytocin were more likely to report feeling positive emotions during guided meditation, such as gratitude, awe, hope, inspiration, love, and serenity.
On analyzing the genotypes of all participants, the researchers found that the link between oxytocin and enhanced spirituality was strongest for men who possessed a specific variant of the gene CD38 - a gene that is known to regulate the release of oxytocin in the hypothalamus.
The authors note that further research is needed to investigate whether oxytocin produces the same effect in women, but they add that their findings provide the first evidence that oxytocin may play a role in our spiritual beliefs.
"Spirituality and meditation have each been linked to health and well-being in previous research. We were interested in understanding biological factors that may enhance those spiritual experiences. Oxytocin appears to be part of the way our bodies support spiritual beliefs.
Spirituality is complex and affected by many factors. However, oxytocin does seem to affect how we perceive the world and what we believe."
Patty Van Cappellen