Adrenal fatigue develops when the adrenal gland is impaired and pumps lower levels of cortisol into the blood, according to WebMD. Cortisol is important for the metabolism of fat, and chronically low levels of the hormone can lead to weight gain.
Cortisol is a steroid hormone that counteracts insulin and helps the body respond to stress, notes About.com. When a person senses a physical or emotional stress, cortisol is released from the adrenal glands. The hormone creates the energy needed to escape or fight a threat by breaking down the nutrients stored in body tissues.
Adrenal glands become fatigued when an individual is chronically exposed to stress, informs About.com. In this state, the adrenal glands fail to produce the amount of cortisol needed for the body to function normally, including a reduced ability to metabolize fat. This causes the majority of glucose provided by the diet to be stored as excess fat, leading to symptoms of fatigue and weight gain.
Although adrenal fatigue is a recognized theory, it is not an accepted medical diagnosis, warns Mayo Clinic. Adrenal fatigue should not be confused with adrenal insufficiency or Addison’s disease. Adrenal insufficiency is a medical diagnosis that is confirmed with a blood test.