Adrenal Fatigue and Women
Like hypothyroidism, adrenal fatigue affects women much more frequently than men. High levels of estrogen cause a corresponding increase in levels of cortisol-binding globulin. Like other hormone-binding globulins, cortisol-binding globulin interferes with hormone function. It circulates in the bloodstream, binds to cortisol, and renders it inactive. A woman with estrogen dominance may have adequate levels of total cortisol in her bloodstream, but her free, available cortisol level may be very low. Only free cortisol can pass through cell membranes and activate receptors inside the cell.
Estrogen impairs adrenal function in another way: it interferes with the release of cortisol from the adrenal cortex. In laboratory animals, when estrogen levels are high, the adrenal cortex fails to respond to signals from the brain. In other words, even though the brain is emitting a cry of alarm—“Send more cortisol!”—the gland responsible for meeting this demand does not “receive” it.
Just as estrogen dominance can contribute to adrenal insufficiency, adrenal insufficiency can contribute to estrogen dominance. Cortisol is made in the adrenal cortex from progesterone. If progesterone levels are low, then cortisol levels are likely to be low as well. Because the body considers cortisol more important to survival than progesterone, whatever progesterone is available in the adrenal cortex is going to be converted into cortisol. This means that a woman whose ovaries are producing less progesterone will not be able to call upon her adrenal glands to produce adequate amounts of cortisol.
As we age, our adrenal glands produce less cortisol. This inevitably leads to adrenal fatigue to one degree or another.
