In October 2020, new research was published on the effects of oxytocin on our mood, relationships with our partner, friends and co-workers. American scientists found that, among other things, it can provoke suspicion, avoidance of contact and envy.
What exactly is known about oxytocin?
"Hug hormone" first of all performs a clear physiological function. Its main function is to promote procreation. Oxytocin is produced in humans and animals, but its potency may vary depending on genetics. Research by Oxford University has shown that the substance is released into the bloodstream during orgasm in both men and women. In the first case, the hormone promotes the rapid movement of sperm. In the second, it stimulates muscle contractions, helping male sex hormones reach their ultimate goal, the egg.
After nine months, oxytocin provokes contractions. Specifically, it stimulates uterine contractions. This is why doctors can inject it into a woman during labor. For the same reason, elevated levels of the hormone are dangerous in the first stages of pregnancy. Later on, oxytocin plays an important role in the lactation process, and also helps establish the psychological connection between mother and child. One way or another, the hormone is really related to processes that evoke pleasant emotions.
Effects of oxytocin on physical health
Research over the past decade shows that the presence of oxytocin in the blood can have a positive effect on human health. Biologists from Ohio University believe the hormone helps wounds heal sooner. Thirty-seven couples participated in the experiment. With their consent, scientists made these people small incisions in the skin. Throughout the time the scratches were healing, doctors measured plasma oxytocin levels. At the same time, the lovers maintained their usual relationship: hugging, kissing, arguing. It turned out that the speed at which the subjects were on the mend depended on the amount of the hormone in the body. Indirectly, this data supports the fact that positive contact with loved ones can have a direct impact on health.
An unexpected experiment, which was performed on rats by doctors from the University of Pennsylvania, also speaks of the benefits of oxytocin. Scientists suggest that the hormone helps to better digest food. Stress is known to negatively affect the gastrointestinal organs. In particular, severe emotional stress can contribute to the retention of food in the stomach. This effect can cause not only bloating, discomfort, nausea and diarrhea, but also provoke more serious problems, including ulcers.
To counteract the stress, researchers decided to use oxytocin as a gastrointestinal stimulant. They injected different doses of the substance into rats' brains and monitored the rodents' reactions. As a result, biologists concluded: the hormone activates the contraction of stomach muscles, which leads to faster digestion of food.
However, it is still too early to treat a sore stomach with hugs. After all, the rodent organism is different from the human body. Nevertheless, in the future, scientists plan to continue experiments that may help develop new therapies for stomach diseases.
Is the hug hormone a myth?
As for hugs, according to research from Harvard Medical School, the greatest release of the hormone occurs in the body immediately before physical contact. Scientists suggest that the stimulus is directly the emotion of waiting for something good, rather than a specific touch.
In other words, hugs do help to reduce stress and increase affection when you and your partner have a warm relationship. But in times of quarrels and resentments, oxytocin is unlikely to help.
Until recently, it was thought that the hormone provided social bonds, helped us trust each other more, and was capable of maintaining monogamy in marriage. However, recent evidence shows that it is not all so straightforward and that the hormone's purpose is much more complex than simply providing a warm relationship.
Many conclusions about the properties of oxytocin have been drawn from experiments with field mice. These rodents remain faithful to their partners for life and are able to show empathy for each other. In particular, in times of stress, the animals try to soothe their loved ones. When scientists blocked oxytocin, laboratory animals immediately lost interest in their soulmates.
Tests of the monogamy hormone theory on humans showed similar results.
For example, an article published in 2012 in the journal Natural Science claimed that married men who received oxytocin nasal spray tended to maintain an emotional distance with unfamiliar attractive women, unlike those who received a placebo.
However, as early as 2018, new data emerged. It turned out that the hormone, which entered the body through the nose, did not always reach the brain and influenced such decisions.
According to other studies, the substance caused opposite emotions in different sexes. While in men it aroused selfishness and competitive tendencies, in women, on the contrary, it aroused empathy and altruism.
Research in recent years proves that the hormone is, above all, a regulator that maintains the stable functioning of the body.
Molecular model of the hormone oxytocin
Effect of oxytocin on psychological health
Most of the hormone is produced in the hypothalamus, the section of the brain that regulates the endocrine system. All the positive feelings associated with it appear here.
However, oxytocin is also produced by another part of the brain, the marginal band supporting nucleus. This compartment is not yet fully understood, but there is speculation that this is where anxiety disorders, depression, and addictions are formed. The reasons for the appearance of oxytocin in this part of the brain were unknown until recently. Experiments on mice showed that it is in the support nucleus where oxytocin provokes anxiety as well as envy. Here it is produced in connection with prolonged stress. However, fleeting emotional outbursts had no effect on oxytocin release.
The responses to the hormone, as in the case of the hypothalamus, were more active in females. Thus, there is a possibility that the new research will shed light on the study and treatment of anxiety disorders, which are more common in women.
obstetrician-gynecologist, candidate of medical sciences, doctor of ultrasonic diagnostics
Oxytocin is a sex-group hormone that is predominantly produced in the female body. However, it is also synthesized in small amounts in men in the hypothalamus. Like any other hormone, it works in tandem with receptors. This means that if there are few receptors for oxytocin on the cells, no matter how many there are in the body, the effect will be small. Receptors, like any other proteins, are encoded in genes.
Years of research have shown that oxytocin receptor gene activity in children depends on maternal care. This factor helps to form the oxytocin system, on which, in turn, the child's adequate socialization depends. Depression, stress and maternal fatigue interfere with the synthesis of this hormone, which can cause muscle contractions and make it difficult for the baby to drink milk.
Oxytocin also regulates the production of the male sex hormone testosterone and promotes its transformation into its active form, dihydrotestosterone. It also reduces the synthesis of cortisol ("stress hormone") and adrenocorticotropic hormone, which are responsible for damaging muscle tissue. That is why it is important to monitor the balance of hormones in the body. An excess of oxytocin adversely affects the adrenal glands, which produce cortisol, so if it is not produced enough, we may experience a decrease in strength. The fact is that this hormone is a vital hormone. It helps us react to and cope with danger. Thanks to cortisol, you can concentrate better, think faster, and get glucose into the blood, which is necessary for the work of the muscles.
Excess oxytocin also inhibits the release of testosterone in the body. This decreases libido, normalizes the level of natural sex hormones and the functionality of the prostate gland.
Why is oxytocin prescribed for men?
Oxytocin has the following effects on the male nervous system:
- elimination of factors of stress development;
- getting rid of the critical sensitivity of others;
- reduction of sexual attraction;
- improvement of emotional susceptibility.
Studies of the results of oxytocin therapy have also shown the effectiveness of this hormone in relieving painful symptoms in menopausal women, for headaches and to improve mood in depression.