Throughout the nation and our world people are suffering from this disease. Depression affects people of genders, all ages, and any background. People once believed that teens never went through any form of severe depression. Some still believe this to be true, but if it were why are teens homicidal and suicidal? This report should give support for the fact that a teen's depression deserves attention, not the shrug of the shoulders or the turn of a back. Depression is defined, as the point or points is ones lifetime when they are mentally unstable and the emotional state marked by sadness, discouragement, and loss that can occur during the teenage years. Depression causes changes in behavior, thinking and especially changes in ones everyday life. "Depression amongst teens generally starts when a child hits puberty, but could possibly begin the day they were born if chemically unbalanced (heredity)." Dr. David Kalkstein, psychiatrist at Penn Foundation. Depression can affect anyone, anytime, and anywhere. Teens, children, and adults are all effected; some even have the same problems in common, the causes too. Depression is experienced mostly by teens even though it is mistakenly classified as an "adult illness". "Twenty percent of high school students are deeply unhappy or have some kind of psychiatric problem." The causes for depression in teens are sometimes more harsh than the causes in adults. In a teen's lifetime they have to face many problems and sometimes they have to face these problems more than once. Teens have to deal with peer pressure problems at school, problems at home, the deaths of loved ones, and if they are already using drugs this could also be a cause. Many teens also have to deal with the point in their life when they wonder if they are attractive to other people, of the opposite sex. If they do believe that they are unattractive they will most likely feel as though they have failed at something.