The most common things nowadays, unfortunately, are stress and anxiety. We experience these on a daily basis.
If you are stressed, then, the amygdala (the brain that contributes to emotional processing) sends a distress signal to the hypothalamus. Also, it uses the nervous system to communicate with the rest of the body this way stimulating the fight-or-flight response.
This leads to outward physical reaction connected to stress like increased heart rate, deeper intake of oxygen, heightened senses, and a rush of adrenaline. This releases cortisol. This hormone will restore all the energy that the body used and when the stress is gone, the levels will drop, thus making you tired.
According to the Mayo Clinic:
‘Stress symptoms may be affecting your health, even though you might not realize it. You may think illness is …