Stress and the Adrenal Glands

No matter what type of stress you encounter—whether it’s physical, chemical, or mental and emotional—your body has an efficient mechanism for coping. This is the important job of the adrenal glands. On the top of each kidney, these small glands work with the brain and nervous system to regulate important coping mechanisms, including the “fight or flight” reaction. The adrenal glands accomplish their work through the production of certain hormones, making them not only essential for stress coping and optimal human performance, but also for life itself. These hormones help with stress regulation, sex and reproduction, growth, aging, cellular repair, electrolyte balance, and blood sugar control.

As noted earlier, cortisol is the key adrenal stress hormone and commonly measured by simple blood and saliva tests. Saliva is a better way to measure cortisol in most instances because having a needle thrust into a vein in your arm evokes stress—and cortisol production—sometimes making the blood test quite inaccurate. A saliva test only requires a small sample of your saliva in a small test tube during the normal course of your day. And, since cortisol fluctuates throughout the day and night, a saliva test can easily be taken four different times throughout the day for a more accurate evaluation.

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When your body is under high stress, cortisol level can increase dramatically, and when the stress passes, the level returns to normal. In chronic stress states—the continuation of stress without relief—high cortisol levels can become dangerous. This can adversely affect the brain, including the pituitary gland, and especially reduce memory, impair aerobic function, create blood sugar problems, reduce fat burning, suppress immune function, lower the body’s defense against not just cold and flu but any infection, and cause intestinal distress. Long-standing stress can result in a “burning out” of adrenal function, with a serious loss of normal hormone production. In this state, cortisol levels become dangerously low, along with other hormones made by the adrenals.

Sex hormones, including estrogens and testosterone, are also important adrenal hormones that help both males and females to maintain proper sexual function and reproductive health. In addition to gonadal sources, these sex hormones come from another important adrenal hormone, DHEA. When stress raises cortisol, DHEA is often reduced.

Excess stress is also the cause of the overtraining syndrome discussed more fully in the next chapter. Whether we call it burnout or overtraining, it’s the same problem. While our understanding of overtraining is relatively new, adrenal stress patterns were discovered nearly a century ago, along with the well-documented three stages of stress, which correlate to the three stages of overtraining.