Depressive disorders affect approximately 18.8 million American adults or about 9.5% of the U.S. population age 18 and older in a given year. Most humans will experience symptoms of depression at some point in his or her life. So it's not uncommon and can include symptoms such as tearfulness, disturbance in sleep or appetite, low mood, lack of motivation or ambition, and feelings of low self esteem. Depression, if left untreated, can deeply affect one's life and will only worsen. If treated, research shows that instances of medical complaints and doctor's visit will decrease, saving money in the long run.