High cortisol levels are positively correlated with increased appetite. Anti-cortisol supplements should, therefore, produce the opposite effect, namely, loss of appetite, amongst others.
Here is why.
As you know, cortisol is a steriod hormone produced in the cortex of the adrenal glands located atop of each kidney. Cortisol secretion occurs irregularly and is triggered by fasting, eating, exercising, the process of waking up, and stressors. Cortisol functions to regulate and mobilize energy. Cortisol carries out its energy-regulating function when it selects the type and amount of carbohydrate, fat or protein that the body requires to satisfy physiological needs. Cortisol carries out its energy-mobilizing function when it moves body fat from one location to another or when it feeds hungry tissue with it.
Furthermore, cortisol can furnish the body with protein for energy production via a process called gluconeogenesis. This is the process of converting amino acids into functional carbohydrate (glucose) in the liver. Cortisol also supports the growth of adipocytes into mature fat cells. Cortisol is also an anti-inflammatory agent.
Increased secretion of cortisol is associated with increased appetite, sugar cravings, and weight gain. This is thought to be because cortisol impacts food ingestion by binding to receptors in the hypothalamus of the brain. This can motivate an individual to crave for and consume food high in fat and or sugar. Furthermore, cortisol also produces an indirect influence on appetite via the regulation of other chemicals released during stress. These include corticotrophin releasing hormone (CRH), leptin, and neuropeptide Y (NPY). Appetite stimulation can occur when levels of NPY and CRH are high and levels of leptin are low.
Anti-cortisol compounds or supplements produce, amongst others, low levels of NPY and CRH and high levels of leptin. These combine to stifle appetite.