What causes depression?
There is no single cause of depression. Instead, depression results from a combination of genetic, biochemical, environmental, and psychological factors. Depression can run in families, and usually starts between the ages of 15 and 30. Possible reasons why a person may become depressed include:

Chemical imbalance - Changes in the brain chemistry

Family history - Depression can be genetically inherited; however, depression can also occur in people with no family history

Hormonal factors - Particularly true for women, depression can be caused by or experienced during menstrual cycle changes, pregnancy, miscarriage, postpartum period, perimenopause, and menopause

Medical illness - llnesses such as stroke, heart attack, cancer can provoke a period of depression

Stress - Stressful situations at work or home may trigger depression

Trauma - Loss of a loved one, or a traumatic experience such as abuse or disaster may provoke or cause depression.

Although depression is more common in women than in men, men experience depression too. Many people experience seasonal affective disorder during the winter months. And depression is one of the characteristic exhibited during bipolar disorder. But how do you know if you are clinically depressed? To learn more about the signs and symptoms of depression, read the "Symptoms of Depression" section that follows.