What effects does stress have on the mind and body?

Why we stress


We’ve all probably heard that stress is bad for your body and mind. But, it can be helpful to understand why we have a stress response in the first place, and how exactly it impacts our cognition, physical health, and emotional well-being.


How does our body respond to stress?


If you’re walking in the jungle and see a jaguar, your body would begin to initiate its stress response. Your amygdala (the fight or flight center of your brain) would activate two other regions of your brain. 


The first is your brain stem, which would mobilize your sympathetic nervous system and release epinephrine and norepinephrine throughout your body. Your heart rate would increase, blood and oxygen would flow to your muscles, and your blood pressure would increase. Other “lower priority” things like reproduction and growth would be paused. This makes a lot of sense - your body doesn’t need to be thinking about reproducing or growth if there’s a jaguar near you.


The second brain region activated would be your hypothalamus, which would stimulate glucocorticoids (cortisol) secretion from your adrenal glands. Glucocorticoids enhance aspects of your cognition and sensory acuity. In short, your body is in a mentally and physically optimal state to either fight or run from the jaguar.


What effects does stress have on the mind and body?


A stressor can be defined as a stimulus that puts your body out of homeostasis. In the above example, the stimulus was the jaguar. However, humans (and other primates) possess a unique ability to observe anticipatory stress. This means that if we anticipate something that will put our body out of homeostasis, that causes a stress response. The anticipation itself is the stimulus -- even if nothing in our immediate surroundings is threatening our homeostasis.


The stress response saves your life in the jungle. But, we’re not generally running away from jaguars in our daily lives. Yet still, our bodies react to stressors in our daily lives in much the same way we respond to the jaguar threat. In short bursts, stress isn’t too bad for us. But, prolonged stress has detrimental effects on the body and mind. We don’t want the consistently high blood pressure or the “pausing” of your reproductive systems that our stress response can cause. This can manifest as ovulatory cycle disruption for women and decreased testosterone levels for men. 


Additionally, prolonged secretion of glucocorticoids negatively impacts both the prefrontal cortex and the hippocampus. The prefrontal cortex is what enables us to control impulses, to be proactive, to delay gratification, and to do the “right thing” when it’s the harder thing to do. The hippocampus powers our memory, our ability to learn, and it plays an important role in being strategic and thinking bigger picture. An increase in cortisol additionally results in us being less empathetic and social. 


In short, prolonged stress has significant negative effects on crucial parts of our brain and body that enable us to be our best selves.



Conclusion

The stress response we get in the jungle when seeing a jaguar is what has enabled us as organisms to survive for so long. The sustained psychological stress we get from worrying about the future, the past, and things that are out of our control hurts us mentally, physically, and emotionally where it matters most. In our modern-day lives, it has become increasingly easy to fall into stress-provoking habits - viewing the littlest of things as a jaguar - making it essential to find ways to decrease stress and improve our body’s response to stress (See “Everything You Need to Know About Adaptogens” to learn about a natural way to improve our stress response).