Addison's disease is a rare and chronic endocrine disorder discovered by Thomas Addison. U.S. President John F. Kennedy is probably one of the most famous sufferers though his condition was kept secret during his presidency. Addision's disease is when the body does not produce enough of the hormone called cortisol. This hormone helps the body deal with stress. It helps with maintaining blood pressure and controlling the heart's functions. It slows the rate of inflammation caused by the body's immune system. It helps with controlling the way insulin is used, and the chemical reactions of proteins, carbohydrates and fats in the body. People with the disease suffer from weight loss, fatigue, weakness and low blood pressure. Some people also get darkened patches of skin. Addison's disease is treated by taking an artificial cortisol tablet.