Depression is an emotional disorder, with certain characteristics, and can be diagnosed in a variety of forms, including bipolar depression (manic-depression), major depression (what we usually think of as depression) and dysthymia (a low-grade, long-lasting form of depression). According to the World Health Organization, depression is now the leading cause of disability, and the fourth contributor to the global burden of disease. Their website has a number of statistics about prevalence of mental illness around the world. Fewer than 25% of people with depression ever seek help for this, among the most treatable of all emotional disorders.

What all forms of depression have in common are:

• persistent sad mood, or feelings of despair or emptiness that don't get better based on circumstances
• lost ability to experience pleasure
• low self-esteem
• problems with motivation, loss of enthusiasm
• social withdrawal, isolation
• negative thinking
• irritability (40% of depressed people are not sad; they are irritated)
• suicidal ideas

If depression persists, it is likely you will also have the physiological symptoms of depression:

• sleep problems (waking up earlier than usual; awakening frequently at night; and/or excessive sleeping)
• appetite disturbance (more or less than usual)
• fatigue
• lowered sex drive
• total loss of the ability to experience pleasure

You may also have:

• restlessness, agitation, and/or feelings of moving slowly
• feeling worse in the morning
• impaired concentration, forgetfulness

Depression and Grief

Depression is not grief. In contrast to depression, when you experience a loss, you may feel numb or terribly sad, but your self-esteem is okay, you don't have physiological symptoms of depression, and you have no suicidal thoughts. (Bereavement does lead to depression in about a third of cases of serious or sudden loss.)