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A: Adrenal fatigue is a controversial syndrome that involves the reduced functioning of the adrenal glands, a pair of small glands located on the kidneys that produce hormones that regulate immune function, blood pressure, metabolism and other important physiological functions. There is disagreement among some scientists and medical experts about whether adrenal fatigue exists as a diagnosable condition — some say it is a real syndrome, while others say there is a lack of scientific evidence to support classifying it as a medical disorder. With adrenal fatigue, it is thought that the adrenal glands are no longer able to produce adequate levels of hormones, including adrenaline and cortisol, to support healthy functioning. The most common cause of adrenal fatigue is chronic stress. Common symptoms of adrenal fatigue include persistent, often intense daytime fatigue, lack of energy and stamina, trouble with focus and concentration and low resilience to illness and stress. If you suspect you may have adrenal fatigue or want to find out more, consult with your family health-care professional or naturopathic doctor.