Gender differences in stress reactions explained

When it comes to stress management, gender matters a lot. Men and women have different coping skills due to subtly different stress reactions in the body and, more importantly, because of a particular hormone that is secreted more in women than in men during stress.

Stress reactions in the body

When you are stressed, your body will be flooded with stress hormones, most notably adrenaline (or epinephrine) and cortisol. Both hormones are secreted from the adrenal glands that are sitting on top of the kidneys.

Adrenaline release is the end result of the activation of the sympathetic nervous system. It makes your heart and breathing go faster, and your muscles tighten. This prepares you for immediate action, the fight-or-flight response to deal with the stressor (a threat, a problem that gives stress).

Cortisol is the end product of the hypothalamus-pituitary-adrenal axis (HPA-axis). Cortisol supports the actions of adrenaline, and helps to  redistribute energy to the organs and cells that become highly active to deal with the stressor.

The sympathetic nervous system and the HPA-axis work the same in men and women. In the past, people used to think that there was a difference in the amounts of cortisol released during a stressful event in men and women. The theory was that women produced more of this hormone, which led to all kinds of bizarre theories of why women are more emotional than men. However, scientists have not been able to show any consistent difference in cortisol production between men and women.

Subtle differences in HPA functioning

Whereas cortisol levels during stress do not differ between men and women, there are two subtle aspects of the functioning of the HPA-axis that diverge between the two sexes. The first is that the adrenal gland of women is more sensitive to the stress hormone ACTH. ACTH is produced by the pituitary gland. It is the intermediary step between the brain (the hypothalamus) and cortisol production (in the adrenal gland). This means that less ACTH is necessary in women to increase cortisol during stress.

The second difference concerns the female sex hormones. They make the HPA-axis less sensitive to the negative feedback of cortisol to shut down the HPA-axis and lower cortisol production once the stress nears its end. Thus, in women, the stress response tends to last longer than in men. Reduced negative feedback, and hence a prolonged stress reaction, is a risk factor for the development of depression. There are researchers who believe that the higher incidence of depression in women when compared with men is partially a consequence of prolonged stress reactions and high cortisol levels.

However, cortisol and adrenaline by themselves are not responsible for differences in stress management strategies that are chosen by men and women.

Oxytocin, the social hormone

If the stress and sex hormones cannot explain the gender difference in behavior during stress, what hormone can? The answer is: oxytocin.

Oxytocin is a hormone that is released by the pituitary, and is also found in the brain. Women may know this hormone well, especially young mothers. Oxytocin is involved in delivery, and is necessary for milk-letdown while breastfeeding a baby. It also helps to bond the mother with the child emotionally. In general, oxytocin reduces anxiety and makes people bond not only with their children, but also with their significant other, with family members and friends. In brief, oxytocin promotes social behavior.

Oxytocin is released during stress. In women, when cortisol and adrenaline rush through the bloodstream, oxytocin is released from the pituitary. It counteracts cortisol and adrenaline production, and at the same time it promotes nurturing and relaxing.

In men, oxytocin is also released during stress, but in much smaller amounts. Therefore, the effects of oxytocin on stress reactions and stress coping are almost negligible.

In both sexes, the stress reactions that lead to the production of adrenaline and cortisol are switched on first. Oxytocin comes a little bit later to help turn them off again. This effect of oxytocin is thus stronger in women than in men.

Stress coping in women: tend and befriend

The high amount of oxytocin released into the blood and in the brain has a major impact on how women deal with stress. An important study carried out by researchers from UCLA and that was published in Psychological Review in 2000, reported that women are more likely to cope with stress by “tending and befriending”. This means that they will nurture the people around them and reach out to others. Tending entails nurturing activities that promote safety and reduce distress in the self and offspring; befriending is the establishment and maintenance of social networks that may aid in this process. Both require a good dose of oxytocin.

The tend and befriend strategy has been confirmed by imaging of brain activity. It turns out that the emotional brain is more active in women than in men during stress.

Stress coping in men: fight or flight

As oxytocin is released in much lower amounts than in women, it is not a surprise that tend and befriending is not commonly found. Rather, the classical fight-or-flight response is dominant, an active and at times aggressive physical response to stress. The typical masculine stress reactions are therefore starting a fight or isolating themselves (flight).

Brain imaging in men has revealed that part of the cortex is more active during stress, whereas another part becomes less active. The active part is important for vigilance, and the inactive part is involved in emotions. Thus, the male brain gets less emotional and more alert, ready for action, during stress.

An evolutionary explanation

What is the origin of tend and befriending in women, and fight-or-flight in men? We already have seen that the hormone oxytocin plays a role in this, but how could the difference in oxytocin signaling during stress have evolved?

Researchers believe that we have to go back to our early ancestors living on the African savannah to answer this question. They think that women might have been better off staying quiet and tending to their children in the face of danger rather than fighting. Fighting would have put both themselves and their children in danger. Fleeing might also not have been the optimal solution, because this may make their children vulnerable to predators or rivaling tribes. Joining forces with others in the group might have been a more valuable strategy. Just like herd animals still do today, seeking safety amongst a large number of individuals might give protection to danger.

Men, on the other hand, would have fought off a predator or any other danger. In this way, they would have protected the tribe, and with that their offspring. Or they could organize and lead a flight, getting the tribe to a safer place and out of harm’s way. Men and women would thus each have their own role in protecting the children.

Many studies have shown that our behavior still reflects these primitive behaviors. A study published in 1997 has shown that on days when women reported their stress levels at work was highest, their children reported that their mothers had been especially loving and nurturing. An earlier study had already shown that fathers who had conflict at work were more likely to have conflict at home on the same day (fight). Similarly, when fathers had a particular stressful day, they tended to withdraw from their families (flight).

Different vulnerability to the consequences of stress

What we have seen until now is that the stress reactions in women can be switched off by oxytocin, and by negative feedback by cortisol in men. Although this difference is not as absolute as black and white (there is also negative feedback by cortisol in women), both oxytocin and cortisol make the stress reactions stop. As stress reactions in women terminate properly as they do in men, where does the idea come from that women are more likely to develop emotional problems because of stress?

A possible answer to this question can be found in the brain. In particular, part of the medial prefrontal cortex (a region important for emotions) is activated in women during stress. This leads to emotional thinking or ruminating. Women tend to reflect more about their own emotions after a stressful event than men.

As mentioned earlier in this article, the tendency that women are more likely to develop depression is related to the compromised cortisol feedback to the HPA-axis to inhibit cortisol production. Apparently, oxytocin alone is not sufficient to reduce the activity of stress reactions in women, but it does help. What happens during depression is that the brain becomes insensitive to cortisol, so that the brain does not know when to stop the stimulation of cortisol production by the adrenal glands. This "sluggish" negative feedback seems to happen more often in women than in men, and scientists believe that female sex hormones are responsible for this.

Gender differences and personality

While there are differences between women and men in stress reactions in the brain and body, and in the choice of coping strategies, personality traits will influence all of these stress responses further. Your response to stress will thus not only depend on whether you are a man or a woman, but also on personality and the type of stressor. Social rejection is for instance more stressful for a woman than for a man. You may also change your stress reactions with experience and age. Being a man or a woman has definitely an influence on how you experience and react to stress, but it is “only” one ingredient of the special sauce that is called stress reactivity. Stress reactivity is unique to each of us, and it is therefore a good thing if you know how to analyze yourself so that you know what stresses you out most, and what you do to overcome stress successfully, or not at all. You can assess this by yourself, with friends and family members, or with professional help. And with Stressinsight of course! Making you understand what stress is, is one of our missions, and you will come to understand yourself better in the process!