Depression is a common but serious mood disorder caused by changes in brain chemistry. It affects approximately 14.8 million American adults. Depression causes severe symptoms that affect how you feel, think and handle daily activities. Symptoms include fatigue, sadness, low sex drive, lack of appetite, feelings of helplessness and disinterest in common activities. Research indicates that other factors contribute to the onset of depression, including genetics, changes in hormone levels, certain medical conditions, stress, grief or difficult life circumstances. Antidepressant medications have serious side effects that can include suicidal thoughts, weight gain and personality changes; what’s worse, studies have shown that antidepressants fail to cure the symptoms of major depression in half of all treated patients.