Oxytocin: The Bonding Hormone

Oxytocin is a hormone that helps relax and reduce blood pressure and cortisol levels. Oxytocin increases pain thresholds, has anti anxiety effects, and stimulates various types of positive social interaction. In addition, it promotes growth and healing. Repeated exposure to oxytocin causes long-lasting effects by influencing the activity of other transmitter systems, a pattern which makes oxytocin potentially clinically relevant. Oxytocin can be released by various types of non-noxious sensory stimulation, for example by touch and warmth. The social interaction of daily life, as well as a positive environment, continuously activate this system. In addition, various types of psychotherapy involving transfer of support, warmth and empathy are likely to induce similar effects, which thus contribute to the positive effects of these kinds of therapies.

How does one increase Oxytocin levels?
Ingestion of food triggers oxytocin release by activation of vagal afferent nerves. Most likely, it can also be released by stimulation of other senses such as olfaction (smell), as well as by certain types of sound and light. In addition, purely psychological mechanisms can trigger the release of oxytocin. This means that positive interaction involving touch and psychological support may be health-promoting.

Oxytocin can be released by various types of sensory stimulation, for example by touch and warmth. Bloodstream levels of oxytocin have been shown to rise during massage.

How does it work?
Oxytocin suppresses the activity of the brain region known as the amygdala, the area that processes fear and communicates it to the rest of the brain. A small sample group of 15 men inhaled either oxytocin or a placebo before performing a task in which they sorted pictures of angry or fearful faces and threatening scenes. During the test, the researchers monitored the subjects’ brain activity with functional magnetic resonance imaging and found that the oxytocin group indeed had reduced activity in the amygdala.

Oxytocin reduces fear!
Animal and human studies indicate the major role of the amygdala in controlling fear and anxiety. The amygdala is involved in detecting threat stimuli and linking them to defensive behaviors. This is accomplished by projections connecting the central nucleus of the amygdala to the brain stem and to hypothalamic structures, which organize fear responses. Oxytocin tempers the excitatory inputs into the amygdala.

Availability of oxytocin drug
Oxytocin is sold as nasal spray (Syntocinon). A nasal spray containing the hormone oxytocin, which is essential to the production and flow of breast milk, does not improve milk output in mothers expressing milk for preterm infants.

Oxytocin and bonding!
The levels of oxytocin hormone in a pregnant woman’s body play a role in how closely she will bond with her newborn. In animals, oxytocin, dubbed “the hormone of love and bonding,” is involved in good parenting and maintaining close relationships. Dr. Ruth Feldman and colleagues at Bar-Ilan University, Ramat-Gan, Israel, studied the role of this hormone in humans and found oxytocin is important in the bonding that occurs between mothers and their infants. Dr. Ruth Feldman and colleagues measured oxytocin levels in 60 pregnant women during the first and third trimester and the first month after delivery. They found that initial levels of oxytocin (first trimester) predicted bonding-related thoughts…as well as maternal bonding to the newborn. Mothers with higher levels of oxytocin at the start of pregnancy showed more bonding behaviors after birth. (Psychological Science, November 2007)

See also:
A great article on the benefits of Oxytocin.
How to increase your oxytocin levels naturally