When you’re stressed out, your adrenal glands are told to produce cortisol. This is because your stress response system, or hypothalamic-pituitary-adrenal axis, sends a message from your hypothalamus to your pituitary gland. Then a new message is sent through your blood and to the adrenal glands.
The cortisol that is secreted attaches to its receptors in order for your cells to receive it and know what they have to do. In case you’re wondering what shuts down this release of cortisol, the receptors are able to tell when it’s time to stop. You can find a long-winded version of this information here.
A helpful quote by Henry Emmons, MD, from this article, is “your body can’t differentiate between a saber-toothed tiger attack and a bad job review.” The biological response is the same. Holly Lucille, ND, RN, also says in the same article that “When you’re overly stressed, you have a decrease in stress resistance.” You’ll understand this if you’re someone who feels drained after any episode of stress.
And stress definitely isn’t just a psychological phenomenon. When you’re under stress, your nervous system will increase your heart rate, constrict some blood vessels and dilate others, slow down the intestines and inhibit digestive processes. When there’s too much cortisol being sent to your brain for a long amount of time, it can create hippocampal brain damage. This disturbs your circadian rhythm (sleep cycle), and you become moody, you experience memory loss, and you get “brain fog”.
Stress can also affect your body fat. Cortisol will give you cravings for quick energy, from carbohydrates and sugar, and can lead to overeating. It also puts excess glucose in your bloodstream. When you don’t burn this off through exercise it gets stored in your body’s tissues as fat.