According to Mayo Clinic, adrenal fatigue refers to a group of symptoms that do not seem to be caused by another illness. Symptoms associated with adrenal fatigue include fatigue, body aches, digestive issues and sleep disturbances.
Mayo Clinic states that the adrenal glands produce many hormones that are necessary to sustain life. If the adrenal glands do not produce enough hormones, then a patient is said to have adrenal insufficiency. Proponents of an adrenal fatigue diagnosis claim that adrenal fatigue is a less severe form of adrenal insufficiency. The diagnosis of adrenal fatigue is not an accepted medical diagnosis and is only considered to be a theory.