Stressed Versus Stressed Out: What's the Difference?
The difference between being "stressed" and being "stressed out" is that being stressed induces an adaptive response (cortisol goes up and then comes down), whereas being stressed out suggests an inability to mount a normal stress response (cortisol rhythm stays flat, so overall cortisol exposure over twenty-four hours is actually higher). It is this nonadaptive cortisol response that scientists at Rockefeller University, in New York, believe leads to most of the common diseases of modern life. Dutch neurology researchers have also observed the very same pattern of flattened cortisol rhythm and nonadaptive stress response in chronic fatigue, fibromyalgia, PTSD, depression, and burnout.
The Type C personality, a term that I coined in the first edition of The Cortisol Connection, has also been called the Type D personality (D for "distressed") by researchers from Columbia University. Like my "always rushed and always busy" Type C person, Columbia's Type D is "characterized by the joint tendency to experience negative emotions and to inhibit these emotions while avoiding social contacts with others." This means Type D people have more of a "depressed" personality than the harried Type C's. The similarity between C's and D's, however, is their overexposure to cortisol, leading some people to feel constantly busy and others to feel depressed. Indeed, researchers from the University of Pennsylvania have recently shown a strong and direct link between stress and tissue breakdown in the brain and in skeletal structures. The Penn scientists found a dramatic association between high cortisol, depression, and reduced bone density—with up to 67 percent of the association between depression and bone density being attributed to stress-induced changes in cortisol levels.
Stages of Stress
When the brain perceives a stressful event, it responds by stimulating endocrine glands throughout the body to release hormones, including both adrenaline and cortisol. Adrenaline is responsible for the "up" feeling that causes excitement, while cortisol is responsible for modulating the way our bodies use various fuel sources. Cortisol is known as a glucocorticoid because it is secreted by the adrenal cortex (thus corticoid) and because it increases levels of blood sugar, or glucose (thus glucocorticoid).
The work of the "father" of stress research, scientist Hans Selye, provides some of the earliest evidence of what we now know as the classic model for adaptation to stress. During experimentation with rats, he observed that given any source of external biological stress, an organism would respond with a predictable biological pattern in an attempt to restore its internal homeostasis. In other words, if stress knocks us out of balance, then our bodies will go through a series of steps (the stress response) to help us regain that balance. He termed this struggle to maintain balance the "general adaptation syndrome," and although modern researchers do not agree with every detail of Selye's stress paradigm, his original division of the stress response into three categories is useful for our purposes in understanding what we can do to combat stress.
Selye proposed that the general adaptation syndrome was the body's way of reacting to a stressor to bring the body's systems back into balance. The first phase of the response, termed the alarm phase, is characterized by an immediate activation of the nervous system and adrenal glands; this is the sudden "jolt" that a stressor delivers to the body. Next comes a phase of resistance, which is characterized by activation of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis is the coordinated system of the three primary endocrine tissues (glands) that mediates our response to stress; in other words, the HPA axis is the "machinery" that helps the body "do its thing" when stress occurs.
So far, everything is perfectly normal: Stress happens and the body reacts immediately (alarm phase) to get things moving, and then works on a more long-term basis (resistance phase) to restore balance. The problems start to occur when we ask the body to react too often (too much alarm) or with excessive exuberance (too much resistance), both of which lead us down the path of having elevated cortisol levels. Under these circumstances, when stress is repeated or constant, cortisol levels go up and stay up, causing a third phase of the general adaptation syndrome that is often referred to as overload. In this overload stage, bodily systems start to break down and our risk for chronic disease skyrockets. This is when we begin to see problems associated with weight gain, immune-system suppression, depression, anxiety, lack of energy, and inability to concentrate. If the overload phase lasts for a prolonged period of time, we can find ourselves in a serious situation, characterized by gastrointestinal ulceration, widespread tissue dysfunction, and profound metabolic derangement.