Hormones are steroid or amino acid based molecules released to the blood that act as chemical messengers to regulate specific body functions. Cortisol is an adrenal corticoid hormone necessary for maintaining blood glucose levels. The body releases cortisol in a highly irregular manner, with peak times early in the morning that taper off during the evening.
Glucose
Glucose is the form of energy used by all of the body's cells and organs. It is sugar that comes from the carbohydrates we eat, such as fruits, vegetables and whole grains. The hormone insulin regulates our blood glucose levels. When glucose enters the bloodstream, the pancreas secretes insulin and transports it to the cells. Insulin changes glucose to glycogen for storage in the muscles and liver. It also stimulates the change of excess glucose to fat for storage.
Cortisol
Cortisol is a metabolic hormone produced by the adrenal cortex. It is necessary for energy production and mobilization. Cortisol chooses the right type and amount of carbohydrates, protein and fat needed to meet the demands of the body. It mobilizes energy by tapping into the fat stores and transporting the fat to different tissues depending on need. Fasting, food intake, exercise and psychological stress are some of the factors that cause the body to release cortisol.
Cortisol and Stress
The body releases cortisol in response to stress. Upon the initial stressor, the body reacts in a "fight or flight" manner. During prolonged stress, the body can become defeated. It releases epinephrine and norepinephrine in the fight or flight reaction. The defeat reaction leads to enhanced fat production, visceral obesity, depressed immune system and breakdown of tissue. In response to stress, cortisol provides the body with protein to promote gluconeogenesis, which is the formation of useable sugar from amino acids in the liver and acts as an anti-inflammatory agent that suppresses the immune system.
Cortisol and Obesity
Cortisol directly affects fat storage and weight gain in stressed people. The body controls tissue cortisol concentrations by a specific enzyme located in the fat tissue that converts inactive cortisone to active cortisol. Research indicates that visceral fat cells contain more of this enzyme than subcutaneous fat. Thus, higher levels of these enzymes in the deep fat surrounding the abdomen may lead to obesity due to the greater amount of cortisol at the tissue level. In addition, abdominal fat has greater blood circulation and four times the amount of cortisol receptors that may increase cortisol's fat accumulating capabilities.
