Stress is a function that's been part of the human existence since there has been a human existence. Put another way, stress is inherent to all of us. Stress does have a role to play, but it too frequently appears when there's no reason for it to be there. Modern living seems to produce stressful situations with ease, leaving many people in perpetual degrees of a chronic stress reaction.

A frequent cause of a stress reaction is anxiety. Anxiety in a general sense is a worry or apprehension about some event, often something in the future. Anxiety isn't the only cause of stress, to be sure: stress can result from anger, sadness, loss, and various other emotional outlooks. There's also the stress that comes from eager anticipation, sometimes referred to as good stress.

When a person experiences stress, the body typically releases cortisol into the bloodstream. Cortisol is a hormone that causes physical changes in the body's response. Specifically, cortisol increases blood pressure and blood sugar. Cortisol is such a regular aspect of the human stress experience that it's come to be called the stress hormone. From a biological standpoint, cortisol's function is to prepare the body to physically respond to an imminent danger. The increasing of blood pressure and blood sugar provides the body an energy solution that can be used in defense or to flee. Cortisol's origins likely go back to the times when our human ancestors faced regular predatory threats.

Cortisol is a double-edged sword, both a help and a hindrance to the body. Elevated rates of blood pressure and blood sugar degenerate vital organs, especially when the elevations are chronic. Increased blood pressure puts strain on the heart, the kidneys, the arteries, brain, and other significant areas of the body as well. Blood sugar at high levels can and does destroy body tissue. From a health standpoint then, we want cortisol to kick in when we absolutely need it, but not otherwise: the effects are potentially too damaging to the body, especially where they occur consistently over time.

Western medicine now appreciates how damaging stress can be, and whole medical programs have been established just for stress reduction. The reality is that most modern human beings very rarely if ever face predatory threat, but the stress reaction remains in place just the same. Turning this stress reaction off in all but the rarest of cases would be a big boost to any person's health.