When felt appropriately, anxiety is beneficial and can keep you out of harm's way... the anxiety you may feel while hiking near a steep drop-off, for instance, will cause you to be more careful and purposeful in your movements.
For an estimated 40 million US adults, however, anxiety may occur even when there's no real threat, causing unnecessary stress and emotional pain. While many believe anxiety and stress to be the same, persistent anxiety actually evokes quite a different experience in your brain.
Anxiety in Your Brain: What Happens When Anxiety Attacks?
Anxiety does evoke the same "fight or flight" response that stress does, which means, like stress, anxiety will trigger a flood of stress hormones like cortisol designed to enhance your speed, reflexes, heart rate, and circulation. However, stress can occur with feelings of anger, sadness, or even happiness and excitement.
Anxiety, on the other hand, virtually always involves a sense of fear, dread, or apprehension. And while stress may occur due to an external source (like an argument with your spouse), anxiety tends to be a more internal response.
Further, brief anxiety may coincide with a stressful event (such as speaking in public), but an anxiety disorder will persist for months even when there's no clear reason to be anxious. While the exact causes for anxiety disorders are unknown, your brain is actively involved.
Comment: One of the most useful things one can do to off-set, ameliorate and even reverse the effects of anxiety and stress is to learn about and practice the techniques shared in Éiriú Eolas.