4.1 Serious depression, as opposed to the fleeting kind we all feel at times, has definite warning signs. 2 One symptom of depression is a change in sleep patterns—either sleeplessness or sleeping too much. 3 In addition, abnormal eating patterns may develop, either eating too much or loss of appetite. 4 A thirdsign is trouble in thinking or concentrating—even to the point of finding it difficult to read a magazine or newspaper. 5 And last of all, a general feeling of hopelessness may signal depression. 6 People feel indifferent to their families and jobs and may begin to think that life is not worth living.