DepressionEveryone occasionally feels blue or sad, but these feelings usually pass within a few hours. Even when dealing with grief or a major sorrow, people typically begin to feel a bit better in a few days. Those suffering from depression, on the other hand, may not be able to identify a reason for their sadness. In contrast to normal feelings of sadness, depression is a more generalized and persistent feeling of gloom or despair that can significantly interfere with a person’s thoughts, mood, behavior, and physical health.