This Is Your Body on Stress

Whether you find yourself facing a minor fender-bender, a looming deadline or a fast-approaching locomotive, any stressful event can trigger a series of well-coordinated, nearly instantaneous reactions in your body. Often known as the “fight-or-flight” response, this process evolved as a survival mechanism for humans and other mammals to react quickly to life-threatening situations, helping them to fight off danger or escape to safety.

While the stressors may have changed over time, the body’s response has not. Dr. Ray Lebeda, family medicine physician with Orlando Health Physician Associates, identifies how different areas of the body are affected by and respond to stress.


Over time, feeling constant muscle tension in your neck can cause your head to ache as well.


Adrenalin heightens your sight, hearing and other senses.


The fight-or-flight tension includes the muscles in the jaw and can cause clenching of the teeth. Stress also can trigger teeth-grinding.


Adrenalin causes the small airways in the lungs to open wider, allowing the lungs to take in more oxygen. The body needs more oxygen to fuel the fight-or-flight response, which can cause you to start breathing more rapidly. In severe cases, it may even lead to hyperventilating.


Adrenalin, the initial stress hormone released, triggers the release

of blood sugar (glucose) and fats from temporary storage sites in the body. These nutrients pour into the bloodstream, bringing a burst of energy to many areas of the body.

Digestive System

Cortisol stops nonessential body functions, including suppressing the digestive system, so that more energy can go toward fighting or fleeing instead of digesting food properly. This can lead to an upset stomach, feeling that knot in the pit of your stomach or even having that “gut feeling.” 


Cortisol, the primary stress hormone, enhances the brain’s use of glucose and can help you focus on a problem while ignoring everything else that’s happening around you. This also explains why some people are able to stay calm and in control during a crisis. Extra oxygen is also sent to the brain, increasing alertness. However, excessive cortisol can kill nerve cells in a crucial area of the brain that helps with memory. This can cause you to forget things when you’re feeling stressed.


Adrenalin causes the heart to beat faster than normal, pushing blood through the heart and to the muscles and other vital organs as the body prepares for action. Pulse rate and blood pressure also go up.


Several factors can trigger stress eating. Feeling anxious can cause you to crave chocolate or carbohydrates, both of which will cause a release of serotonin, a feel-good chemical, in the brain. And even though it’s short-term, those calorie- and fat-heavy foods make us feel better. Some research also indicates that stress might increase the hunger hormones.

Palms and Underarms

Your body wants to cool off, in case you need to start the flight response, causing you to perspire. 


The fight-or-flight response causes muscles to tense up, as your body prepares itself to either fight the danger or escape from it. That constant tension can worsen existing muscular conditions or cause new muscle pain.


The fight-or-flight reaction pushes blood flow to the muscles, and thus away from the skin. This change in blood flow can either make you look paler or flush, depending on the person. For some, stress triggers a release of histamine, which can cause hives or rashes. 

If you have concerns about how you may be responding to stress, talk with a primary care physician about possible treatment or management options. Locate a doctor at

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